KR20150036286A

KR20150036286A - Passivation layer forming composition, semiconductor substrate with passivation layer and manufacturing method thereof, solar cell device and manufacturing method thereof, and solar cell

Info

Publication number: KR20150036286A
Application number: KR20157002562A
Authority: KR
Inventors: 슈이치로 아다치; 마사토 요시다; 다케시 노지리; 야스시 구라타; 도루 다나카; 아키히로 오리타; 쓰요시 하야사카
Original assignee: 히타치가세이가부시끼가이샤
Priority date: 2012-07-12
Filing date: 2013-07-12
Publication date: 2015-04-07
Also published as: CN104471715B; TWI615395B; CN106935664A; TW201412761A; JPWO2014010743A1; CN104471715A; WO2014010743A1

Abstract

The composition for forming a passivation layer of the present invention comprises at least one alkoxide compound selected from the group consisting of titanium alkoxide, zirconium alkoxide and silicon alkoxide, . In the following general formula (I), R ¹ independently represents an alkyl group having 1 to 8 carbon atoms; n represents an integer of 0 to 3; X ² and X ³ each independently represent an oxygen atom or a methylene group; R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

Description

TECHNICAL FIELD [0001] The present invention relates to a composition for forming a passivation layer, a semiconductor substrate on which a passivation layer is formed, a method of manufacturing the same, a solar cell element, a method of manufacturing the same, THEREOF, AND SOLAR CELL}

The present invention relates to a composition for forming a passivation layer, a semiconductor substrate on which a passivation layer is formed, a manufacturing method thereof, a solar cell element and a manufacturing method thereof, and a solar cell

A manufacturing process of a conventional silicon solar cell will be described.

First, a p-type silicon substrate on which a textured structure is formed on the light receiving surface side is prepared so as to promote the optical confinement effect and to achieve high efficiency. Subsequently, phosphorous oxychloride (POCl ₃ ) is doped in a mixed gas atmosphere of nitrogen Deg.] C to 900 [deg.] C for several tens of minutes to uniformly form the n-type diffusion layer.

In this conventional method, since phosphorus is diffused by using a mixed gas, an n-type diffusion layer is formed not only on the surface that is the light receiving surface but also on the side surface and the back surface. Therefore, side etching is performed to remove the n-type diffusion layer formed on the side surface. Further, the n-type diffusion layer formed on the back surface needs to be converted into a p ⁺ -type diffusion layer. Therefore, an aluminum paste including aluminum powder and a binder is applied to the entire back surface, and the aluminum paste is subjected to heat treatment (firing) to form an aluminum electrode, whereby the n-type diffusion layer is formed as a p ⁺ -type diffusion layer, ) Contacts.

However, the aluminum electrode formed from the aluminum paste has a low conductivity. Therefore, in order to lower the sheet resistance, generally, the aluminum electrode formed on the entire surface must have a thickness of about 10 mu m to 20 mu m after heat treatment (baking). In addition, since the thermal expansion rate of silicon and aluminum is greatly different, a large internal stress is generated in the silicon substrate in the course of the heat treatment (sintering) and cooling in the silicon substrate having the aluminum electrode formed thereon, It causes damage, increases crystal defects, and causes warpage.

In order to solve this problem, there is a method of reducing the thickness of the back electrode layer by reducing the application amount of the aluminum paste. However, when the application amount of the aluminum paste is reduced, the amount of aluminum diffused from the surface of the p-type silicon semiconductor substrate into the inside becomes insufficient. As a result, there is a problem that the desired BSF (Back Surface Field) effect (the effect of improving the collection efficiency of the generated carrier due to the presence of the p ⁺ -type diffusion layer) can not be achieved, .

With regard to the above, there has been proposed a point contact method in which an aluminum paste is applied to a part of the surface of a silicon substrate to partially form a p ⁺ diffusion layer and an aluminum electrode (see, for example, Japanese Patent No. 3107287) .

In the case of a solar cell having a point contact structure on the side opposite to the light receiving surface (hereinafter, also referred to as " back side "), on the surface of the portion other than the aluminum electrode, . An SiO ₂ film or the like has been proposed as a passivation layer for backside (hereinafter, simply referred to as a "passivation layer") (see, for example, Japanese Unexamined Patent Application Publication No. 2004-6565). As the passivation effect by forming such an oxide film, there is an effect of reducing the density of surface level which causes recombination by terminating the unbonded hand of silicon atoms in the surface layer portion of the back surface of the silicon substrate.

As another method for suppressing the recombination of minority carriers, there is a method of reducing the minority carrier density by an electric field generated by a fixed charge in the passivation layer. Such a passivation effect is generally called a field effect, and an aluminum oxide (Al ₂ O ₃ ) film or the like has been proposed as a material having a negative charge (for example, refer to Japanese Patent No. 4767110) .

Such a passivation layer is generally formed by an ALD (Atomic Layer Deposition) method or a CVD (Chemical Vapor Deposition) method (see, for example, Journal of Applied Physics, 104 (2008), 113703-1 to 113703 -7.). As a simple method for forming an aluminum oxide film on a semiconductor substrate, a sol-gel method has been proposed (see, for example, Thin Solid Films, 517 (2009), 6327-6330, and Chinese Physics Letters, 26 ), 088102-1 to 088102-4).

On the other hand, when a layer having a large refractive index and a large passivation effect is formed on the light-receiving surface side of the silicon substrate, the light confinement effect and the recombination speed of the minority carriers can be suppressed and the power generation efficiency of the solar cell can be increased . For example, there has been proposed a method of forming an oxide film in which a metal such as titanium is combined with aluminum by a sol-gel method to increase the refractive index of the film (see, for example, Japanese Journal of Applied Physics, 45 (2006), 5894-5901 .

Since the method described in Journal of Applied Physics, 104 (2008), 113703-1 to 113703-7 includes a complicated manufacturing process such as vapor deposition, it has been difficult to improve the productivity. In the composition for forming a passivation layer used in the method described in Thin Solid Films, 517 (2009), 6327 to 6330, and Chinese Physics Letters, 26 (2009), 088102-1 to 888102-4. It is difficult to say that storage stability is sufficient due to problems such as gelation. Further, it is difficult to say that the passivation layer according to the method described in Japanese Journal of Applied Physics, 45 (2006), 5894 to 5901. is sufficiently high in refractive index, and there is a fear of photocatalytic action derived from titanium oxide, There is a possibility of damaging the sealing resin.

It is an object of the present invention to provide a composition for forming a passivation layer which is capable of forming a passivation layer having a sufficiently large refractive index in a desired shape by a simple method and is excellent in storage stability . Further, the present invention provides a semiconductor substrate obtained by using the composition for forming the passivation layer and having a passivation layer having a passivation layer having a sufficiently high refractive index formed thereon, a method of manufacturing the same, a solar cell element and a manufacturing method thereof, and a solar cell .

Specific means for solving the above problems are as follows.

<1> A composition for forming a passivation layer, which comprises an organoaluminum compound represented by the following general formula (I) and at least one alkoxide compound selected from the group consisting of titanium alkoxide, zirconium alkoxide and silicon alkoxide.

[Chemical Formula 1]

[In the formula (I), each R ¹ independently represents an alkyl group having 1 to 8 carbon atoms. n represents an integer of 0 to 3; X ² and X ³ each independently represent an oxygen atom or a methylene group. R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms,

<2> The composition for forming a passivation layer according to <1>, further comprising a niobium alkoxide.

<3> The passivation according to <2>, wherein the niobium alkoxide is at least one selected from the group consisting of niobium ethoxide, niobium isopropoxide, niobium n-propoxide, niobium n-butoxide and niobium phenoxide. Lt; / RTI >

(4) The method according to (1), wherein the alkoxide compound comprises at least the titanium alkoxide, and the titanium alkoxide is at least one compound selected from the group consisting of titanium methoxide, titanium ethoxide, titanium isopropoxide, titanium n- At least one selected from the group consisting of titanium tetrabutoxide, titanium isobutoxide, titanium (diisopropoxide) bis (acetylacetonate) and titanium (tetrakis (2-ethyl-1-hexanolate) The composition for forming a passivation layer according to any one of <1> to <3>.

&Lt; 5 > The method according to < 5 >, wherein the alkoxide compound contains at least the zirconium alkoxide, and the zirconium alkoxide is at least one selected from the group consisting of zirconium ethoxide, zirconium isopropoxide, zirconium n- The composition for forming a passivation layer according to any one of <1> to <4>, wherein the composition is at least one selected from the group consisting of zirconium acetylacetone, zirconium trifluoroacetylacetonate and zirconium hexafluoroacetylacetonate.

<6> The passivation layer according to any one of <1> to <5>, wherein the alkoxide compound includes at least the silicon alkoxide and the silicon alkoxide is a silicon alkoxide represented by the following general formula (II) / RTI >

(R ⁵ O) _(4-m) SiR ⁶ _m (II)

[In the formula (II), R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 8 carbon atoms. and m represents an integer of 0 to 3.]

<7> The composition for forming a passivation layer according to any one of <1> to <6>, which further comprises a resin.

<8> The composition for forming a passivation layer according to any one of <1> to <7>, further comprising a compound represented by the following general formula (III).

(2)

<9> A semiconductor substrate having a semiconductor substrate and a passivation layer having a passivation layer which is a heat treatment product of a composition for forming a passivation layer according to any one of <1> to <8> which is provided on an entire surface or a part of the semiconductor substrate.

<10> A method of manufacturing a semiconductor device, comprising the steps of: providing a composition for forming a passivation layer according to any one of <1> to <8> on an entire surface or a part of a semiconductor substrate to form a composition layer; And forming a passivation layer on the semiconductor substrate.

<11> A semiconductor device, comprising: a semiconductor substrate in which a p-type layer and an n-type layer are pn junctioned; and a passivation layer as a heat treatment product of a composition for forming a passivation layer according to any one of <1> to < And an electrode disposed on at least one layer selected from the group consisting of the p-type layer and the n-type layer of the semiconductor substrate.

<12> A semiconductor substrate having a pn junction formed by bonding a p-type layer and an n-type layer and having electrodes on at least one layer selected from the group consisting of the p-type layer and the n-type layer, , A step of forming a composition layer by applying the composition for forming a passivation layer described in any one of < 1 > to < 8 &

A step of heat-treating the composition layer to form a passivation layer

Gt; a < / RTI > solar cell element.

The solar cell element according to < 13 >

A wiring material disposed on the electrode of the solar cell element

&Lt; / RTI >

According to the present invention, a passivation layer having a sufficiently high refractive index can be formed into a desired shape by a simple method, and a composition for forming a passivation layer having excellent storage stability can be provided. According to the present invention, there is also provided a semiconductor substrate having a passivation layer formed using a composition for forming a passivation layer, the passivation layer having a passivation layer having a sufficiently high refractive index, and a manufacturing method thereof, a solar cell element and a manufacturing method thereof, and a solar cell .

1 (a) to 1 (d) are cross-sectional views schematically showing an example of a method of manufacturing a solar cell element having a passivation layer according to an embodiment of the present invention.
2 (a) to 2 (e) are cross-sectional views schematically showing another example of a method of manufacturing a solar cell element having a passivation layer according to an embodiment of the present invention.
3 is a cross-sectional view schematically showing a back electrode type solar cell element having a passivation layer according to an embodiment of the present invention.

In this specification, the term " process " is included in this term, as long as the purpose of the process is achieved, even if it can not be clearly distinguished from other processes, as well as an independent process. The numerical range indicated by " ~ " indicates a range including numerical values before and after " ~ " as the minimum value and the maximum value, respectively. The content of each component in the composition refers to the total amount of the plurality of substances present in the composition unless otherwise specified when a plurality of substances corresponding to each component are present in the composition. In the present specification, the term " layer " includes not only a configuration of a shape formed on an entire surface when viewed as a plan view, but also a configuration of a shape formed on a part thereof.

&Lt; Composition for forming passivation layer >

The composition for forming a passivation layer of the present invention is characterized by containing an organoaluminum compound represented by the following general formula (I) (hereinafter also referred to as a "specific organoaluminum compound") and a titanium alkoxide, a zirconium alkoxide and a silicon alkoxide (Hereinafter also referred to as " specific alkoxide compound "). The composition for forming the passivation layer may further include other components as necessary. Since the composition for forming the passivation layer contains a specific organoaluminum compound and a specific alkoxide compound, the passivation layer having a sufficiently high refractive index can be formed into a desired shape by a simple method. The composition for forming the passivation layer is also excellent in storage stability.

(3)

In the general formula (I), each R ¹ independently represents an alkyl group having 1 to 8 carbon atoms. n represents an integer of 0 to 3; X ² and X ³ each independently represent an oxygen atom or a methylene group. R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Herein, when a plurality of any one of R ¹ , R ² , R ³ , R ⁴ , X ² and X ³ is present, the groups represented by the same symbols which exist in plural may be the same or different.

A passivation layer forming composition containing a specific organoaluminum compound and a specific alkoxide compound is applied to a semiconductor substrate to form a composition layer having a desired shape and then heat treated (baked) to obtain a passivation layer having a sufficiently large refractive index A passivation layer having a desired shape can be formed. The method of the present invention is a simple and highly productive method that does not require a deposition apparatus or the like. Further, the passivation layer can be formed in a desired shape without requiring a troublesome process such as mask processing. In addition, since the composition for forming the passivation layer contains a specific organoaluminum compound and a specific alkoxide compound, problems such as gelation over time are suppressed, and the storage stability is excellent.

In the present specification, the passivation effect of the semiconductor substrate is obtained by measuring the effective lifetime of the minority carriers in the semiconductor substrate on which the passivation layer is formed by using a device such as WT-2000PVN (Semilabo, It can be evaluated by measuring by the damping method.

Here, the effective lifetime tau is represented by the following formula (A) by the bulk lifetime? _B in the semiconductor substrate and the surface lifetime? _S of the surface of the semiconductor substrate. When the surface level density of the surface of the semiconductor substrate is small, τ _s becomes long, and the effective lifetime (τ) becomes long. Further, even if defects such as dangling bonds in the semiconductor substrate are reduced, the bulk lifetime? _B is prolonged and the effective lifetime tau becomes long. That is, it is possible to evaluate the interfacial characteristics between the passivation layer and the semiconductor substrate and the internal characteristics of the semiconductor substrate such as the short-circuited bond by measuring the effective lifetime tau.

1 / τ = 1 / τ _b + 1 / τ _s (A)

And, the longer the effective lifetime, the slower the recombination rate of minority carriers. In addition, conversion efficiency is improved by constructing a solar cell element using a semiconductor substrate having a long effective lifetime.

(Specific organoaluminum compound)

The composition for forming the passivation layer contains at least one of the organoaluminum compounds represented by the general formula (I) (hereinafter also referred to as " specific organoaluminum compounds "). The organoaluminum compound preferably contains a compound such as an aluminum alkoxide, an aluminum chelate and the like, and preferably has an aluminum chelate structure in addition to the aluminum alkoxide structure. Also, as described in Nippon Seramikkusu Kyokai Gakujitsu Ronbunshi, 97 (1989) 369-399, a specific organoaluminum compound is converted to aluminum oxide (Al ₂ O ₃ ) by heat treatment (sintering).

The inventors of the present invention have considered the reason why a passivation layer having a passivation layer can be formed by containing the organoaluminum compound represented by the general formula (I) in the composition for forming the passivation layer.

Aluminum oxide formed by heat-treating (firing) a passivation layer-forming composition containing a specific organoaluminum compound and a specific alkoxide compound tends to be in an amorphous state. Therefore, the quaternary coordination aluminum oxide layer is formed near the interface with the semiconductor substrate (-) fixed charge due to tetracoordinated aluminum oxide. This large negative fixed charge generates an electric field in the vicinity of the interface of the semiconductor substrate, so that the concentration of the minority carriers can be lowered. As a result, the rate of carrier recombination at the interface is suppressed, so that a passivation layer having excellent passivation effect can be formed . Further, it is considered that the inclusion of a specific alkoxide compound in addition to the organoaluminum compound increases the refractive index of the passivation layer to be formed.

Here, the state of the tetracoordinated aluminum oxide layer, which is the cause of the negative fixed charge on the surface of the semiconductor substrate, is determined by the electron energy loss spectroscopy method (STEM, Scanning Transmission Electron Microscope) EELS, and Electron Energy Loss Spectroscopy). 4-coordinated aluminum oxide is considered to have a structure in which the center of silicon dioxide (SiO ₂ ) is isomorphous to silicon from aluminum, and is formed as a negative charge source at the interface between silicon dioxide and aluminum oxide, such as zeolite and clay.

The state of the formed aluminum oxide layer can be confirmed by measuring X-ray diffraction (XRD). For example, if XRD does not show a specific reflection pattern, it can be confirmed that it is an amorphous structure. The negative fixed voltage of the aluminum oxide can be evaluated by the CV method (Capacitance Voltage measurement). However, the surface level density obtained by the CV method for the heat-treated layer of aluminum oxide formed from the composition for forming a passivation layer of the present invention is larger than that of the aluminum oxide layer formed by the ALD method or the CVD method . However, the passivation layer formed from a passivation layer for forming the composition of the present invention, the field effect a decrease in the concentration of large minority carrier surface increases the lifetime (τ _s). Therefore, the surface level density is not a relatively serious problem.

In the general formula (I), each R ¹ independently represents an alkyl group having 1 to 8 carbon atoms, and is preferably an alkyl group having 1 to 4 carbon atoms. The alkyl group represented by R ¹ may be linear or branched. Specific examples of the alkyl group represented by R ¹ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a hexyl group, , 3-ethylhexyl group and the like. Among them, the alkyl group represented by R ¹ is preferably an unsubstituted alkyl group having 1 to 8 carbon atoms, more preferably an unsubstituted alkyl group having 1 to 4 carbon atoms, from the viewpoints of storage stability and passivation effect.

In the general formula (I), n represents an integer of 0 to 3. n is preferably an integer of 1 to 3, more preferably 1 or 3, from the viewpoint of storage stability. And X ² and X ³ each independently represent an oxygen atom or a methylene group. From the viewpoint of storage stability, it is preferable that at least one of X ² and X ³ is an oxygen atom.

R ² , R ³ and R ⁴ in the general formula (I) each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. The alkyl group represented by R ² , R ³ and R ⁴ may be a straight chain or branched chain. The alkyl group represented by R ² , R ³ and R ⁴ may have a substituent or may be unsubstituted, but is preferably amorphous. The alkyl group represented by R ² , R ³ and R ⁴ is preferably an alkyl group having 1 to 8 carbon atoms and an alkyl group having 1 to 4 carbon atoms. The alkyl group represented by R ² , R ³ or R ⁴ is preferably an alkyl group having 1 to 8 carbon atoms and an alkyl group having 1 to 4 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a hexyl group, an octyl group, For example.

Among them, R ² and R ³ in the general formula (I) are each preferably a hydrogen atom or an unsubstituted alkyl group having 1 to 8 carbon atoms, and preferably a hydrogen atom or an alkyl group having 1 to 8 carbon atoms in terms of storage stability and passivation effect More preferably an unsubstituted alkyl group having from 1 to 4 carbon atoms.

R ⁴ in the general formula (I) is preferably a hydrogen atom or an unsubstituted alkyl group having 1 to 8 carbon atoms, more preferably a hydrogen atom or an unsubstituted alkyl group having 1 to 4 carbon atoms, from the viewpoints of storage stability and passivation effect Is more preferable.

The organoaluminum compound represented by the general formula (I) is preferably a compound wherein n is 1 to 3 and R ⁴ is each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, from the viewpoint of storage stability.

The organoaluminum compound represented by the general formula (I) is a compound in which n is 0, R ¹ is each independently an alkyl group having 1 to 4 carbon atoms, and n is an integer of 1 to 3 from the viewpoints of storage stability and passivation effect and, the R ¹ is an alkyl group having 1 to 4 carbon atoms, each independently, X ² and X ³ is at least one oxygen atom, R ² and R ³ a is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, each independently, R ⁴ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

More preferably, the organoaluminum compound represented by the general formula (I) is a compound wherein n is 0, R ¹ is each independently an unsubstituted alkyl group having 1 to 4 carbon atoms, and n is an integer of 1 to 3 , R ¹ is each independently an unsubstituted alkyl group having 1 to 4 carbon atoms, at least one of X ² and X ³ is an oxygen atom, and R ² or R ³ bonded to the oxygen atom is an alkyl group having 1 to 4 carbon atoms , And when X ² or X ³ is a methylene group, it is more preferable that R ² or R ³ bonded to the methylene group ^{is a} hydrogen atom and R ⁴ is a hydrogen atom.

Specific examples of the organoaluminum compound (aluminum trialkoxide) in which n is 0 in the formula (I) include trimethoxy aluminum, triethoxy aluminum, triisopropoxy aluminum, tri-sec-butoxy aluminum, mono butoxy diisopropoxy aluminum, sec-butoxy diisopropoxy aluminum, tri-tert-butoxy aluminum, tri-n-butoxy aluminum and the like.

Specific examples of the organoaluminum compound represented by the general formula (I), wherein n is an integer of 1 to 3, specifically include aluminum ethylacetoacetate diisopropylate, aluminum methylacetoacetate diisopropylate, aluminum tris (ethylacetoacetate ), Aluminum monoacetylacetonate bis (ethylacetoacetate), aluminum tris (acetylacetonate), and the like.

In the general formula (I), a specific organoaluminum compound in which n is an integer of 1 to 3 may be prepared or a commercially available product may be used. ALCH-50 F, ALCH-75, ALCH-TR, ALCH-TR-20, aluminum chelate M, aluminum chelate D, aluchimilate A (W).

A specific organoaluminum compound represented by the general formula (I) in which n is an integer of 1 to 3 can be prepared by mixing the above-mentioned aluminum trialkoxide with a compound having a specific structure having the above two carbonyl groups. A commercially available aluminum chelate compound may also be used.

When the aluminum trialkoxide is mixed with a compound having a specific structure having two carbonyl groups, at least a part of the alkoxide groups of the aluminum trialkoxide is substituted with a compound having a specific structure to form an aluminum chelate structure. At this time, a solvent may be present if necessary, and a heat treatment, addition of a catalyst, and the like may be performed. By replacing at least a part of the aluminum alkoxide structure with the aluminum chelate structure, the stability against the hydrolysis and polymerization reaction of a specific organoaluminum compound is improved, and the storage stability of the composition for forming a passivation layer is further improved. Further, the closer the reactivity with the niobium alkoxide, the titanium alkoxide, the zirconia alkoxide and the silicon alkoxide, which will be described later, is, the more easily, the complex oxide having a small photocatalytic action and a large refractive index becomes easy to be produced.

The compound having a specific structure having two carbonyl groups is preferably at least one selected from the group consisting of a? -Diketone compound, a? -Ketoester compound and a malonic acid diester from the viewpoints of reactivity and storage stability. Specific examples of the compound having a specific structure having two carbonyl groups include acetylacetone, 3-methyl-2,4-pentanedione, 2,3-pentanedione, 3-ethyl- Pentanedione, 2,2,6,6-tetramethyl-3,5-heptanedione, 2,6-dimethyl-3,5-heptanedione, 6-methyl- Of the? -Diketone compound; Butyl acetoacetate, pentyl acetoacetate, isopentyl acetoacetate, hexyl acetoacetate, n-octyl acetoacetate, heptyl acetoacetate, heptyl acetoacetate, isopropyl acetoacetate, isopropyl acetoacetate, isopropyl acetoacetate, Ethyl acetoacetate, ethyl 2-butylacetoacetate, ethyl 4,4-dimethyl-3-oxovalerate, ethyl 4-methyl-3-oxovalerate, ethyl 2-ethylacetoacetate, , Ethyl hexyl acetoacetate, methyl 4-methyl-3-oxovalerate, isopropyl acetoacetate, ethyl 3-oxohexanoate, ethyl 3-oxovalerate, methyl 3-oxovalerate, ? -Ketoester compounds such as ethyl 2-methylacetoacetate, ethyl 3-oxoheptanoate, methyl 3-oxoheptanoate and methyl 4,4-dimethyl-3-oxovalerate; Diethyl malonate, diethyl malonate, dipropyl malonate, diisopropyl malonate, dibutyl malonate, di-tert-butyl malonate, dihexyl malonate, tert-butyl ethyl malonate, diethyl methyl malonate , Diethyl ethylmalonate, diethyl isopropylmalonate, diethyl butylmalonate, diethyl sec-butylmalonate, diethyl isobutylmalonate, and malonic acid diester such as diethyl 1-methylbutylmalonate and the like For example.

When the specific organoaluminum compound has an aluminum chelate structure, the number of aluminum chelate structures is not particularly limited as long as it is 1 to 3. Among them, from the viewpoint of storage stability, the number of aluminum chelate structures is preferably 1 or 3, more preferably 1 from the viewpoint of solubility. The number of aluminum chelate structures can be controlled, for example, by appropriately adjusting the mixing ratio of the aluminum trialkoxide to the compound capable of forming a chelate with aluminum. Compounds having a desired structure can also be appropriately selected from commercially available aluminum chelate compounds.

Among the organoaluminum compounds represented by the general formula (I), specifically from the viewpoint of the passivation effect and the compatibility with a solvent to be added as required, aluminum ethylacetoacetate diisopropylate and triisopropoxy Aluminum, and aluminum ethyl acetoacetate diisopropylate is more preferably used.

The presence of the aluminum chelate structure in the specific organoaluminum compound can be confirmed by a commonly used analytical method. For example, infrared spectroscopy spectrum, nuclear magnetic resonance spectrum, melting point, or the like.

The content ratio of the specific organoaluminum compound contained in the composition for forming the passivation layer can be appropriately selected as needed. The content of the organoaluminum compound may be 1% by mass to 70% by mass, preferably 3% by mass to 60% by mass, more preferably 5% by mass to 60% by mass in the composition for forming a passivation layer, from the viewpoints of storage stability and passivation effect, More preferably 50% by mass, and still more preferably 10% by mass to 30% by mass.

The organoaluminum compound may be in the form of a liquid or a solid, and is not particularly limited. From the viewpoints of the passivation effect and the storage stability, it is preferable to use a specific organoaluminum compound having good stability at room temperature (25 DEG C) and good solubility or dispersibility as a solvent when a solvent is used. By using such a specific organoaluminum compound, the homogeneity of the formed passivation layer is further improved, and a desired passivation effect tends to be stably obtained.

(Specific alkoxide compound)

The composition for forming a passivation layer of the present invention may contain, in addition to a specific organoaluminum compound, at least one alkoxide compound selected from the group consisting of titanium alkoxide, zirconium alkoxide and silicon alkoxide (hereinafter also referred to as a "specific alkoxide compound" ). By containing at least one selected from the specific alkoxide compounds, a complex oxide having a large refractive index can be produced together with the organoaluminum compound, and the passivation effect can be further improved.

The passivation layer formed by the heat treatment (baking) of the composition for forming a passivation layer of the present invention has a higher refractive index than that of the passivation layer formed only of the organoaluminum compound. For example, in a solar cell element in which a passivation layer having a large refractive index is formed on a light receiving surface, the use efficiency of light is further improved, and the power generation efficiency is improved. The refractive index of the passivation layer formed from the composition for forming a passivation layer is preferably 1.4 or more, more preferably 1.6 or more, and further preferably 1.6 to 2.5.

The titanium alkoxide is not particularly limited and may be appropriately selected from titanium alkoxides generally used. Among them, it is preferable that the titanium alkoxide is reacted with the organoaluminum compound represented by the general formula (I) to form a complex and give a more dense composite oxide in view of difficulty in decomposing the resin or the like in contact with the passivation layer to be formed. Specific examples of the titanium alkoxide include titanium alkoxide, titanium ethoxide, titanium isopropoxide, titanium n-propoxide, titanium n-butoxide, titanium tert-butoxide, titanium isobutoxide, Isopropoxide) bis (acetylacetonate), titanium tetrakis (2-ethyl-1-hexanolate), and the like. In general, it is known that titanium oxide obtained by heat-treating (firing) titanium alkoxide has a large refractive index. However, when titanium oxide itself is added to a composition for forming a passivation layer, there is a possibility of decomposing the resin or the like in contact with the passivation layer under sunlight or the like due to the photocatalytic action of the titanium oxide. On the other hand, in the case of applying the titanium alkoxide to the composition for forming the passivation layer, the titanium alkoxide can form a complex oxide together with the organoaluminum compound to form a passivation layer with a suppressed photocatalytic action and a high refractive index.

The zirconium alkoxide is not particularly limited as long as it reacts with the organoaluminum compound represented by the formula (I) to give a composite oxide. Specific examples of the zirconium alkoxy include zirconium ethoxide, zirconium isopropoxide, zirconium n-propoxide, zirconium n-butoxide, zirconium tert-butoxide, zirconium acetylacetone, zirconium trifluoroacetylacetonate, Hexafluoroacetylacetonate, and the like. Generally, it is known that zirconium oxide obtained by heat-treating (firing) a zirconium alkoxide has a large refractive index. However, when zirconium oxide itself is added to a composition for forming a passivation layer, there is a possibility of decomposing the resin or the like in contact with the passivation layer under sunlight or the like due to the photocatalytic action of the zirconium oxide. On the other hand, when the zirconium alkoxide is applied to the composition for forming the passivation layer, the zirconium alkoxide forms a complex oxide together with the organoaluminum compound to suppress the photocatalytic action and to form the passivation layer having a large refractive index.

The silicon alkoxide will be described. Aluminum oxide formed by heat treatment (firing) of the passivation layer-forming composition containing the organoaluminum compound represented by the general formula (I) tends to be in an amorphous state, and partly tetrahedral aluminum oxide is produced. When 4-coordinated aluminum oxide is generated, a negative fixed charge can be obtained. When a silicon alkoxide is contained in the passivation layer forming composition, quadrival silicon oxide is produced together with heat treatment (firing). 4 coordination silicon oxide is known to be substituted from silicon to aluminum by central substitution by homologous substitution. Therefore, if tetracoordinated silicon oxide is formed in the aluminum oxide layer, as a result, aluminum oxide in four coordinates having a negative fixed charge tends to be generated. Since the refractive index of the silicon oxide itself obtained by heat-treating (firing) the silicon alkoxide is smaller than that of the aluminum oxide, aluminum oxide of four coordinates, which is a negative fixed charge source, tends to be generated by compounding, By using an alkoxide, a more excellent passivation effect can be obtained.

The silicon alkoxide is not particularly limited as long as it reacts with the organoaluminum compound represented by the formula (I), the titanium alkoxide, the zirconium alkoxide or the niobium alkoxide optionally contained to give the composite oxide. Among them, the silicon alkoxide is preferably a compound represented by the following general formula (II).

(R ⁵ O) _(4-m) SiR ⁶ _m (II)

In the formulas, R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 8 carbon atoms. n represents an integer of 0 to 3; Here, if there is a plurality of any of R ⁵ and R ⁶ are a plurality existence R ⁵ or R ⁶ which may be the same as each may be different.

As the silicon alkoxide, specifically, there may be mentioned, for example, cyclic tetramethoxide, cyclic tetraethoxide, cyclic tranaproxide and the like.

Among the alkoxide compounds selected from the group consisting of titanium alkoxide, zirconium alkoxide and silicon alkoxide, from the viewpoints of reactivity with the organoaluminum compound, refractive index of the resulting composite oxide, and passivation effect, the titanium alkoxide and zirconium alkoxide , And it is more preferable to use at least one member selected from the group consisting of titanium isopropoxide, zirconium ethoxide and zirconium isopropoxide, and more preferably titanium isopropoxide It is more preferable to use at least one species selected from the group consisting of a seed and a zirconium ethoxide.

The content of the specific alkoxide compound selected from the group consisting of titanium alkoxide, zirconium alkoxide and silicon alkoxide is preferably from 0.5% by mass to 65% by mass, more preferably from 1% by mass to 65% by mass in the composition for forming a passivation layer By mass, more preferably 2% by mass to 60% by mass.

The ratio of the content of the specific alkoxide compound to the content of the organoaluminum compound represented by the general formula (I) (the specific alkoxide compound / the organoaluminum compound represented by the general formula (I)) is From the viewpoints of refractive index and passivation effect, it is preferably 0.01 to 1000, more preferably 0.05 to 500, and still more preferably 0.1 to 100.

(Niobium alkoxide)

The composition for forming the passivation layer may contain at least one of niobium alkoxide. Since niobium oxide obtained by heat-treating (firing) niobium alkoxide is known to have a high refractive index, a passivation layer having a higher refractive index can be obtained by heat-treating (firing) the composition for forming a passivation layer further containing niobium alkoxide.

The niobium alkoxide is not particularly limited as long as it reacts with the organoaluminum compound represented by the formula (I) to give a composite oxide. Specific examples of the niobium alkoxide include niobium ethoxide, niobium isopropoxide, niobium n-propoxide, niobium n-butoxide and niobium phenoxide.

When the composition for forming the passivation layer contains niobium alkoxide, the content thereof is preferably 0.2 mass% to 50 mass%, more preferably 0.5 mass% to 48 mass%, in the total mass of the composition for forming a passivation layer , More preferably from 1% by mass to 46% by mass.

When the composition for forming the passivation layer contains niobium alkoxide, the ratio of the content of the niobium alkoxide to the content of the organoaluminum compound represented by the general formula (I) (niobium alkoxide / Organoaluminum compound) is preferably from 0.01 to 1,000, more preferably from 0.05 to 500, and even more preferably from 0.1 to 100 from the viewpoints of the refractive index and the passivation effect of the resulting composite oxide.

When the composition for forming the passivation layer contains niobium alkoxide, the ratio of the total content of the specific alkoxide compound and the niobium alkoxide to the content of the organoaluminum compound represented by the general formula (I) Is preferably from 0.01 to 1,000, more preferably from 0.05 to 500, and even more preferably from 0.1 to 100 from the viewpoints of refractive index and passivation effect.

In the composition for forming the passivation layer, the total content of the organoaluminum compound, the specific alkoxide compound and optionally the niobium alkoxide represented by the general formula (I) in the composition for forming the passivation layer is preferably 1% By mass to 70% by mass, more preferably 3% by mass to 60% by mass, still more preferably 5% by mass to 50% by mass.

(Suzy)

The composition for forming the passivation layer may further contain at least one kind of resin. By including the resin, the shape stability of the composition layer formed by imparting the composition for forming a passivation layer on the semiconductor substrate is further improved, and the passivation layer can be selectively formed into a desired shape in the region where the composition layer is formed .

The kind of the resin is not particularly limited. When the composition for forming a passivation layer is applied onto a semiconductor substrate, it is preferable that the resin is a resin capable of adjusting the viscosity to such an extent that a good pattern can be formed. Specific examples of the resin include polyvinyl alcohol, polyacrylamides, polyvinylamides, polyvinylpyrrolidone, polyethylene oxides, polysulfonic acid, polyacrylamide alkylsulfonic acid, cellulose, carboxymethylcellulose, hydroxyethylcellulose, Gelatin and gelatin derivatives, starch and starch derivatives, sodium alginate and sodium alginate derivatives, xanthan and xanthan derivatives, guar gum and guar gum derivatives, scleroglucan and scleroglucan, (Meth) acrylate resin (for example, an alkyl (meth) acrylate resin, a dimethylaminoethyl (meth) acrylate, and a methyl methacrylate resin), a polysaccharide derivative, a polysaccharide derivative, a polysaccharide derivative, a glucoglucan derivative, a tragacanth and a tragacanth derivative, a dextrin and a dextrin derivative, Late resin, etc.), butadiene resin, styrene resin, siloxane resin, There is a copolymer and the like. These resins may be used singly or in combination of two or more kinds.

Among these resins, from the viewpoints of storage stability and pattern forming property, it is preferable to use a neutral resin having no acidic or basic functional group. Even when the content is small, it is possible to easily control the viscosity and thixo , It is more preferable to use a cellulose derivative.

The molecular weight of these resins is not particularly limited, and it is preferable to adjust them appropriately in consideration of a desired viscosity as a composition for forming a passivation layer. The weight average molecular weight of the resin is preferably from 1,000 to 10,000,000, more preferably from 3,000 to 5,000,000 from the viewpoints of storage stability and pattern formability. The weight average molecular weight of the resin is determined from the molecular weight distribution measured using GPC (gel permeation chromatography) using the calibration curve of standard polystyrene.

When the composition for forming the passivation layer contains a resin, the content of the resin in the composition for forming the passivation layer may be appropriately selected as needed. The content of the resin is preferably 0.1% by mass to 30% by mass, for example, in the total mass of the composition for forming a passivation layer. The content is more preferably from 1% by mass to 25% by mass, still more preferably from 1.5% by mass to 20% by mass, even more preferably from 1.5% by mass to 20% by mass, from the viewpoint of exhibiting thixo- By mass to 10% by mass.

When the composition for forming the passivation layer contains a resin, the content ratio of the organic aluminum compound and the resin in the composition for forming the passivation layer may be appropriately selected as required. Among them, from the viewpoints of the pattern formation property and the storage stability, the content ratio of the resin to the organoaluminum compound (resin / organoaluminum compound) is preferably 0.001 to 1000, more preferably 0.01 to 100, Is more preferable.

(High boiling point material)

A high boiling point material may be used in the composition for forming the passivation layer as a material in place of or in place of the resin. The high boiling point material is preferably a compound which does not need to be easily vaporized and subjected to degreasing treatment at the time of heating. The high boiling point material is particularly preferably a high boiling point material having a high viscosity capable of maintaining the printing form after printing application. As a material satisfying these requirements, there is, for example, isobornylcyclohexanol represented by the general formula (III).

[Chemical Formula 4]

The isobonylcyclohexanol represented by the general formula (III) is commercially available as " TERSOLV MTPH " (trade name of Terpene Chemical Co., Ltd., Japan). Isobornylcyclohexanol has a boiling point as high as 308 ° C to 318 ° C, and when removed from the composition layer, it is not necessary to perform degreasing treatment by heat treatment (calcination) like a resin, . Therefore, in the drying step after coating the composition for forming the passivation layer on the semiconductor substrate, most of the solvent and isobornylcyclohexanol contained in the composition as needed can be removed, so that the black residue after the heat treatment (calcination) ) Can be suppressed.

When the composition for forming the passivation layer contains a high boiling point material, the content of the high boiling point material is preferably 0.5% by mass to 85% by mass, and more preferably 1% by mass to 80% by mass in the total mass of the composition for forming a passivation layer , And particularly preferably from 2% by mass to 80% by mass.

(menstruum)

The composition for forming the passivation layer may include a solvent. The composition for forming the passivation layer contains a solvent so that the adjustment of the viscosity becomes easier and the parenchyma is more improved and a more uniform passivation layer can be formed. The solvent is not particularly limited and may be appropriately selected according to need. Among them, a solvent capable of dissolving the organoaluminum compound and the specific alkoxide compound represented by the general formula (I) to give a uniform solution is preferable, and it is more preferable to include at least one kind of organic solvent.

Specific examples of the solvent include acetone, methyl ethyl ketone, methyl n-propyl ketone, methyl isopropyl ketone, methyl n-butyl ketone, methyl isobutyl ketone, methyl n-pentyl ketone, Ketone solvents such as diethyl ketone, dipropyl ketone, diisobutyl ketone, trimethylnonanone, cyclohexanone, cyclopentanone, methylcyclohexanone, 2,4-pentanedione and acetonyl acetone; Examples of the organic solvent include diethyl ether, methyl ethyl ether, methyl n-propyl ether, diisopropyl ether, tetrahydrofuran, methyltetrahydrofuran, dioxane, dimethyl dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol methyl-n-propyl ether, diethylene glycol methyl-n-butyl Diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether, diethylene glycol methyl-n-hexyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol methyl ethyl Ether, triethylene glycol methyl-n-butyl ether, triethylene glycol di-n-butyl ether, triethylene glycol methyl-n-hexyl ether, Tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol methyl ethyl ether, tetraethylene glycol methyl-n-butyl ether, tetraethylene glycol di-n-butyl ether, tetraethylene glycol methyl- Propylene glycol diethyl ether, propylene glycol di-n-propyl ether, propylene glycol dibutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, diethylene glycol diethyl ether, diethylene glycol di- Propylene glycol diethyl ether, dipropylene glycol methyl ethyl ether, dipropylene glycol methyl n-butyl ether, dipropylene glycol di-n-propyl ether, dipropylene glycol di-n-butyl ether, dipropylene glycol methyl n-hexyl ether, Ether, tripropylene glycol diethyl ether, tripropylene glycol methyl ethyl ether, tri N-hexyl ether, tetrapropyleneglycol dimethyl ether, tetrapropyleneglycol diethylether, tetrapropyleneglycol methylethylether, tetrapropyleneglycol methylethylether, tripropyleneglycol methylethylether, tripropyleneglycol methylethylether, Ether solvents such as tetrapropylene glycol methyl-n-butyl ether, tetrapropylene glycol di-n-butyl ether, tetrapropylene glycol methyl-n-hexyl ether and tetrapropylene glycol di-n-butyl ether; Propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, (2-butoxyethoxy) ethyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, nonyl acetate, methyl acetoacetate, ethyl acetate, diethylene glycol acetate Propylene glycol dimethyl ether, glycol methyl ether, acetic acid diethylene glycol monoethyl ether, acetic acid dipropylene glycol methyl ether, dipropylene glycol ethyl ether acetate, diacetic acid glycol, methoxytriethylene glycol acetate, ethyl propionate, n-butyl propionate, Di-n-butyl oxalate, methyl lactate, ethyl lactate, lactate Propyleneglycol ethyl ether acetate, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol monomethyl ether acetate, Ester solvents such as propylene glycol propyl ether acetate,? -Butyrolactone and? -Valerolactone; N-methylpyrrolidinone, N-ethylpyrrolidinone, N-propylpyrrolidinone, N-butylpyrrolidinone, N-hexylpyrrolidinone, N-cyclohexylpyrrolidinone, N, N- Aprotic polar solvents such as dimethylformamide, N, N-dimethylacetamide and dimethylsulfoxide; Hydrophobic organic solvents such as methylene chloride, chloroform, dichloroethane, benzene, toluene, xylene, hexane, octane, ethylbenzene, 2-ethylhexanoic acid, methylisobutylketone and methyl ethyl ketone; Butanol, tert-butanol, n-pentanol, isopentanol, 2-methylbutanol, sec-pentanol, tert-pentanol, 3-pentanol, Hexanol, sec-hexanol, sec-heptanol, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl But are not limited to, alcohol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, cyclohexanol, methylcyclohexanol, benzyl alcohol, , Alcohol solvents such as 1,3-butylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol and tripropylene glycol; Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol mono-n-hexyl Glycol monoether solvents such as ether, ethoxy triglycol, tetraethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether and tripropylene glycol monomethyl ether ; terpene solvents such as? -terpinene,? -terpineol, myrcene, aloocimene, limonene, dipentene,? -pinene,? -pinene, terpineol, carbone, ocimene and pellandrene; Water, and the like. These may be used alone or in combination of two or more.

Among them, the solvent preferably contains at least one member selected from the group consisting of a terpene solvent, an ester solvent and an alcohol solvent from the viewpoints of the adhesion to the semiconductor substrate and the pattern forming property, And at least one kind selected from the group consisting of

When the composition for forming the passivation layer contains a solvent, the content of the solvent is determined in consideration of the pseudo-female, pattern-forming property, and storage stability. For example, the content of the solvent is preferably 5% by mass to 98% by mass, more preferably 10% by mass to 95% by mass, in the total mass of the composition for forming a passivation layer, desirable.

(Other additives)

The composition for forming the passivation layer may contain an acidic compound or a basic compound. When the composition for forming the passivation layer contains an acidic compound or a basic compound, the content of the acidic compound or the basic compound in the passivation layer-forming composition is preferably 1% by mass or less, more preferably 0.1% by mass or less, Is more preferable.

Examples of the acidic compound include Bronsted acid and Lewis acid. Specifically, inorganic acids such as hydrochloric acid and nitric acid, and organic acids such as acetic acid and the like can be mentioned. Examples of basic compounds include Bronsted bases and Lewis bases. Specific examples include inorganic bases such as alkali metal hydroxides and alkaline earth metal hydroxides, and organic bases such as trialkylamines and pyridines.

(Physical property value)

The viscosity of the composition for forming the passivation layer is not particularly limited, and can be appropriately selected depending on the method of giving to the semiconductor substrate and the like. For example, the viscosity of the composition for forming the passivation layer may be 0.01 Pa · s to 10000 Pa · s. Among them, the viscosity of the composition for forming a passivation layer is preferably from 0.1 Pa · s to 1000 Pa · s from the viewpoint of pattern forming property. The viscosity is measured at 25 DEG C and a shear rate of 1.0 s < ^-1 > using a rotary shear viscometer.

The shear viscosity of the composition for forming the passivation layer is not particularly limited, and it is preferable that the composition for forming the passivation layer has a thixo property. Particularly, when the composition for forming the passivation layer contains a resin, the shear viscosity (? ₁ ) at a shear rate of 1.0 s ^-1 is divided by the shear viscosity (? ₂ ) at a shear rate of 10 s ^-1 (Η ₁ / η ₂ ) calculated by the above equation is preferably 1.05 to 100, more preferably 1.1 to 50. The shear viscosity was measured at a temperature of 25 DEG C using a rotary shear viscometer equipped with a cone plate (diameter 50 mm, cone angle 1 DEG).

On the other hand, when the composition for forming the passivation layer contains a high boiling point material in place of the resin, the shear viscosity? ₁ at a shear rate of 1.0 s ^-1 at a shear rate of 1000 s ^-1 (? ₃ (Η ₁ / η ₃ ) calculated by dividing the total consumption by the total amount (η ₁ / η ₃ ) is preferably 1.05 to 100, more preferably 1.1 to 50.

(Method for producing a composition for forming a passivation layer)

The method for producing the composition for forming the passivation layer is not particularly limited. For example, by mixing the organoaluminum compound represented by the general formula (I), the specific alkoxide compound and optionally a resin, a solvent or the like by a commonly used mixing method. Or by dissolving the resin in a solvent, and then mixing the resultant with the organoaluminum compound represented by the general formula (I) and the specific alkoxide compound.

The organoaluminum compound represented by the general formula (I) can also be prepared by mixing an aluminum alkoxide and a compound capable of forming a chelate with aluminum. At this time, a solvent may be used if necessary, or a heat treatment may be performed. A composition for forming a passivation layer may be prepared by mixing the organoaluminum compound represented by the general formula (I) and the specific alkoxide compound thus prepared with a solution containing a resin or a resin.

The components contained in the composition for forming the passivation layer and the content of each component can be determined by thermal analysis such as simultaneous differential thermal and thermal weight measurement (TG / DTA), nuclear magnetic resonance (NMR), infrared spectroscopy For example, by spectral analysis of high-performance liquid chromatography, high-performance liquid chromatography (HPLC), or gel permeation chromatography (GPC).

&Lt; Semiconductor substrate on which passivation layer is formed &

The semiconductor substrate on which the passivation layer of the present invention is formed includes a semiconductor substrate and a passivation layer which is a heat treatment product (fired product) of the composition for forming a passivation layer of the present invention, which is provided on the whole surface or a part of the semiconductor substrate I have. The semiconductor substrate on which the passivation layer is formed has a passivation layer which is a heat treatment layer (baked layer) of the composition for forming the passivation layer, thereby exhibiting an excellent passivation effect.

The semiconductor substrate is not particularly limited, and can be appropriately selected from those conventionally used depending on the purpose. As the semiconductor substrate, silicon, germanium or the like can be exemplified by doping (diffusing) p-type impurity or n-type impurity. Among them, a silicon substrate is preferable. The semiconductor substrate may be a p-type semiconductor substrate or an n-type semiconductor substrate. Among them, from the viewpoint of the passivation effect, it is preferable that the surface on which the passivation layer is formed is a p-type semiconductor substrate. The p-type layer on the semiconductor substrate may be a p-type layer derived from a p-type semiconductor substrate or a p-type diffusion layer or a p ⁺ -type diffusion layer formed on an n-type semiconductor substrate or a p-type semiconductor substrate.

The thickness of the semiconductor substrate is not particularly limited and may be appropriately selected according to the purpose. For example, the thickness of the semiconductor substrate may be 50 mu m to 1000 mu m, preferably 75 mu m to 750 mu m.

The average thickness of the passivation layer formed on the semiconductor substrate is not particularly limited and may be appropriately selected according to the purpose. For example, the average thickness of the passivation layer is preferably 5 nm to 50 mu m, more preferably 10 nm to 30 mu m, and further preferably 15 nm to 20 mu m. The average thickness of the passivation layer can be measured by an interference type film thickness meter or the like.

The semiconductor substrate on which the passivation layer is formed may be applied to a solar cell element, a light emitting diode element, or the like. For example, a solar cell element having excellent conversion efficiency can be obtained by applying it to a solar cell element. When the semiconductor substrate on which the passivation layer is formed is applied to a solar cell element, the passivation layer is preferably provided on the light receiving surface side of the solar cell element.

&Lt; Manufacturing Method of Semiconductor Substrate Having Passivation Layer >

A method of manufacturing a semiconductor substrate on which a passivation layer of the present invention is formed includes the steps of forming a composition layer by applying a composition for forming a passivation layer of the present invention to an entire surface or a part of a semiconductor substrate, Thereby forming a passivation layer. The above production method may further include other processes as necessary.

By using the composition for forming the passivation layer, the passivation layer having a superior passivation effect and a large refractive index can be formed into a desired shape by a simple method.

It is preferable that the method of manufacturing a semiconductor substrate having the passivation layer further includes a step of applying an aqueous alkali solution onto the semiconductor substrate before the step of forming the composition layer. That is, it is preferable to clean the surface of the semiconductor substrate with an alkaline aqueous solution before applying the composition for forming the passivation layer on the semiconductor substrate. By washing with an alkaline aqueous solution, organic substances and fine particles existing on the surface of the semiconductor substrate can be removed, and the passivation effect is further improved. As a cleaning method using an alkali aqueous solution, generally known RCA cleaning and the like can be mentioned. For example, organic substrates and fine particles can be removed and cleaned by immersing the semiconductor substrate in a mixed solution of aqueous ammonia and hydrogen peroxide at a temperature of 60 ° C to 80 ° C. The cleaning time is preferably 10 seconds to 10 minutes, more preferably 30 seconds to 5 minutes.

In the RCA cleaning, the wafer is first placed in a hydrofluoric acid aqueous solution (HF) to dissolve the thin Si oxide film on the surface, and also remove many foreign substances adhering to it. Further, as described above, organic substances and fine particles are removed by using a mixed solution of ammonia water (NH ₄ OH) and hydrogen peroxide (H ₂ O ₂ ), and then hydrochloric acid (HCl) and hydrogen peroxide (H ₂ O ₂ ) Remove the metal type. Finally, ultrapure water can be used to finish.

The method for forming the composition layer by applying the composition for forming the passivation layer on the semiconductor substrate is not particularly limited. For example, there is a method of applying the composition for forming the passivation layer on a semiconductor substrate using a known coating method or the like. Specifically, examples of the method include a dipping method, a printing method, a spinning method, an oval coating method, a spraying method, a doctor blade method, a roll coater method, and an ink jet method. Of these, various printing methods, inkjet methods and the like are preferable from the viewpoint of pattern forming property.

The amount of the composition for forming the passivation layer may be appropriately selected according to the purpose. For example, it is possible to appropriately adjust the thickness of the passivation layer to be formed to be a desired thickness to be described later.

The passivation layer can be formed on the semiconductor substrate by heat treating (baking) the composition layer formed by the composition for forming the passivation layer and forming the heat treatment layer (baked layer) derived from the composition layer.

The heat treatment (firing) condition of the composition layer is preferably such that the organoaluminum compound represented by the general formula (I) and the specific alkoxide compound contained in the composition layer are mixed with the heat-treated (fired) aluminum oxide (Al ₂ O ₃ ) But is not particularly limited as long as it can be converted into an oxide. Among them, it is preferable to be a heat treatment (firing) condition capable of forming a layer containing an amorphous Al ₂ O ₃ having no specific crystal structure. Since the passivation layer is composed of the layer containing Al ₂ O ₃ in the amorphous phase, it is possible to make the passivation layer more effectively negative and obtain a more excellent passivation effect. Specifically, the heat treatment (baking) temperature is preferably 400 占 폚 to 900 占 폚, more preferably 450 占 폚 to 800 占 폚. The heat treatment (baking) time can be appropriately selected depending on the heat treatment (baking) temperature and the like. For example, it may be 0.1 hour to 10 hours, preferably 0.2 hours to 5 hours.

The thickness of the passivation layer produced by the method of manufacturing a semiconductor substrate having the passivation layer is not particularly limited and may be appropriately selected according to the purpose. For example, the average thickness of the passivation layer is preferably 5 nm to 50 탆, more preferably 10 nm to 30 탆, and further preferably 15 nm to 20 탆.

The average thickness of the formed passivation layer can be measured by a conventional method using a contact type step and surface shape measuring device (for example, Ambios), an interference type film thickness measuring device (for example, The thickness of three points is measured, and the arithmetic mean value is calculated.

The method of manufacturing a semiconductor substrate having the passivation layer may include a step of applying a composition for forming a passivation layer and then drying the composition layer comprising the composition for forming a passivation layer before a step of forming the passivation layer by heat treatment You can have more. By including the step of drying the composition layer, a passivation layer having a more uniform passivation effect can be formed.

The step of drying the composition layer is not particularly limited as long as at least a part of the solvent that can be contained in the composition for forming the passivation layer can be removed. The drying treatment can be carried out, for example, at 30 to 250 캜 for 1 to 60 minutes, preferably at 40 to 220 캜 for 3 to 40 minutes. The drying treatment may be carried out under atmospheric pressure or under reduced pressure.

In the case where the composition for forming the passivation layer comprises a resin, the method for manufacturing a semiconductor substrate on which the passivation layer is formed is characterized in that after the composition for forming the passivation layer is provided, before the step of forming the passivation layer by heat treatment (firing) A step of degreasing the composition layer made of the composition for a substrate. By including the step of degreasing the composition layer, a passivation layer having a more uniform semiconductor substrate passivation effect can be formed.

The step of degreasing the composition layer is not particularly limited as long as at least a part of the resin that can be contained in the composition for forming the passivation layer can be removed. The degreasing treatment can be performed, for example, at a temperature of 250 ° C to 400 ° C for 3 minutes to 120 minutes, and is preferably a heat treatment at 300 ° C to 450 ° C for 10 minutes to 60 minutes. The degreasing treatment is preferably performed in the presence of oxygen, more preferably in the air.

The solar cell element of the present invention comprises a semiconductor substrate in which a p-type layer and an n-type layer are pn-bonded to each other, and a passivation layer which is a heat treatment (fired product) of the composition for forming a passivation layer of the present invention, And an electrode disposed on at least one layer selected from the group consisting of the p-type layer and the n-type layer of the semiconductor substrate. The solar cell element may further have other components as necessary.

The solar cell element has a passivation layer formed from the composition for forming a passivation layer of the present invention, so that the conversion efficiency is excellent.

The semiconductor substrate to which the composition for forming the passivation layer is applied is not particularly limited and may be suitably selected from those conventionally used depending on the purpose. As the semiconductor substrate, those described in the semiconductor substrate on which the passivation layer is formed can be used, and the same can be used preferably. The surface of the semiconductor substrate on which the passivation layer is formed may be a p-type layer or an n-type layer. Among them, a p-type layer is preferable from the viewpoint of conversion efficiency. The p-type layer on the semiconductor substrate may be a p-type layer derived from a p-type semiconductor substrate or a p-type diffusion layer or a p ⁺ -type diffusion layer formed on an n-type semiconductor substrate or a p-type semiconductor substrate. The surface of the semiconductor substrate on which the passivation layer is formed is preferably a light receiving surface in a solar cell element.

The thickness of the semiconductor substrate is not particularly limited and may be appropriately selected according to the purpose. For example, it may be 50 mu m to 1000 mu m, preferably 75 mu m to 750 mu m.

The thickness of the passivation layer formed on the semiconductor substrate is not particularly limited and may be appropriately selected according to the purpose. For example, the average thickness of the passivation layer is preferably from 5 nm to 50 탆, more preferably from 10 nm to 30 탆, and further preferably from 15 nm to 20 탆.

The shape, size, etc. of the solar cell element are not limited. For example, it is preferable that one side is a square having a width of 125 mm to 156 mm.

A manufacturing method of a solar cell element of the present invention is a method of manufacturing a solar cell element having a semiconductor substrate having a pn junction formed by bonding a p-type layer and an n-type layer and having electrodes on at least one layer selected from the group consisting of a p- Forming a composition layer by applying the composition for forming a passivation layer of the present invention to at least a part of the surface having the passivation layer of the present invention; and heat-treating (firing) the composition layer to form the passivation layer. The solar cell element manufacturing method may further include other steps as required.

By using the composition for forming a passivation layer, a solar cell element having an excellent passivation effect, a passivation layer having a high refractive index, and excellent conversion efficiency can be manufactured by a simple method. Further, the passivation layer can be formed on the semiconductor substrate having the electrode formed thereon to have a desired shape, and the productivity of the solar cell element is excellent.

The semiconductor substrate having the pn junction where the electrode is disposed on at least one of the p-type layer and the n-type layer can be produced by a commonly used method. For example, an electrode forming paste such as silver paste or aluminum paste may be applied to a desired region of a semiconductor substrate, followed by heat treatment (firing) if necessary.

The surface of the semiconductor substrate on which the passivation layer is formed may be a p-type layer or an n-type layer. Among them, a p-type layer is preferable from the viewpoint of conversion efficiency.

The method of forming the passivation layer using the composition for forming the passivation layer is the same as the method of manufacturing the semiconductor substrate having the passivation layer described above, and the preferred embodiment is the same.

Next, an embodiment of the present invention will be described with reference to the drawings.

1 (a) to 1 (d) are cross-sectional views schematically showing an example of a method for manufacturing a solar cell element having a passivation layer according to the present embodiment. However, this flowchart does not limit the present invention.

As shown in Fig. 1A, an n ^& lt ^{; + &} gt ^; -type diffusion layer 2 is formed in the vicinity of the surface of the p-type semiconductor substrate 1, and an antireflection film 3 is formed on the outermost surface. Examples of the antireflection film 3 include a silicon nitride film and a titanium oxide film. A surface protective film (not shown) such as silicon oxide may be further present between the antireflection film 3 and the p-type semiconductor substrate 1. The passivation layer according to the present invention is preferably formed between the antireflection film 3 and the p-type semiconductor substrate 1 (not shown) because the passivation layer has a large refractive index. Although not shown in Figs. 1 (a) to 1 (d), a method of manufacturing a solar cell element having a passivation layer on the light-receiving surface side will be described later with reference to Fig.

Next, as shown in Fig. 1 (b), a material for forming the back electrode 5 such as an aluminum electrode paste is applied to a part of the back surface of the p-type semiconductor substrate 1 and then heat-treated (baked) The back electrode 5 is formed and aluminum atoms are diffused into the p-type semiconductor substrate 1 to form the p ^& lt ^{; + &} gt ^; -type diffusion layer 4.

1 (c), an electrode forming paste is coated on the light receiving surface side of the p-type semiconductor substrate 1 and then heat treatment (baking) is performed to form the light receiving surface electrode 7. 1 (c), the surface of the n ^& lt ^{; +} & gt ^; -type diffusion layer 2 is covered with the antireflection film 3, The light receiving surface electrode 7 can be formed to obtain an ohmic contact.

1 (b) and 1 (c) are shown as separate steps in FIGS. 1 (a) to 1 (d) ) May be combined into one process. 1 (b), a material for forming the back electrode 5 such as an aluminum electrode paste is applied to a part of the back surface, and then a heat treatment for forming the back electrode 5 ), A paste for electrode formation may be applied to the light-receiving surface side, and heat treatment (baking) may be performed at this stage. In this method, the electrodes on the back surface and the light receiving surface are formed by one heat treatment, and the process is simplified.

Then, as shown in Fig. 1 (d), a composition layer is formed by applying a composition for forming a passivation layer on the p-type layer on the back surface other than the region where the back electrode 5 is formed. Granting can be done, for example, by a method such as screen printing. The composition layer formed on the p-type layer is subjected to heat treatment (firing) to form the passivation layer 6. By forming the passivation layer 6 formed from the composition for forming the passivation layer on the back p-type layer, a solar cell element having excellent power generation efficiency can be produced.

In the solar cell element manufactured by the manufacturing method including the manufacturing steps shown in Figs. 1 (a) to 1 (d), the back contact electrode formed of aluminum or the like can be made into a point contact structure, Can be reduced. Further, by using the composition for forming the passivation layer, the passivation layer can be formed with excellent productivity only at a specific position (specifically, a p-type layer other than the region where the electrode is formed).

1D, a method of forming a passivation layer only on the back surface of the semiconductor substrate 1 is shown. However, in addition to the back surface of the semiconductor substrate 1, a composition for forming a passivation layer is also provided on the side surface , And the passivation layer 6 may be further formed on the side surface (edge) of the semiconductor substrate 1 by heat treatment (firing) (not shown). This makes it possible to manufacture a solar cell element having better power generation efficiency.

Further, the passivation layer may be formed by applying the composition for forming the passivation layer of the present invention only on the side surface, without forming the passivation layer on the back surface portion, and by heat treatment (firing). The effect of the composition for forming a passivation layer of the present invention is particularly large when the composition is used at a site having many crystal defects such as a side face.

1 (a) to 1 (d), the passivation layer is formed after the electrodes are formed. However, after the formation of the passivation layer, an electrode such as aluminum may be formed in a desired region by vapor deposition or the like.

2 (a) to 2 (e) are cross-sectional views schematically showing another example of a method of manufacturing a solar cell element having a passivation layer according to an embodiment of the present invention. Specifically, Fig. (A) ~ (e) of FIG. 2 by using the p ⁺ type diffusion layer of formable p-type diffusion layer-forming composition for an aluminum electrode paste or thermal diffusion process to form a p ⁺ type diffusion layer Sectional view showing a process step including a step of removing the heat-treated product of the aluminum electrode paste or the heat-treated product of the composition for forming the p ^& lt ^{; + &} gt ^; -type diffusion layer. Here, as the composition for forming the p-type diffusion layer, for example, there is a composition containing an acceptor element-containing substance and a glass component.

As shown in Fig. 2A, an n ^& lt ^{; + &} gt ^; -type diffusion layer 2 is formed in the vicinity of the surface of the p-type semiconductor substrate 1, and an antireflection film 3 is formed on the surface. Examples of the antireflection film 3 include a silicon nitride film and a titanium oxide film.

Then, as shown in FIG. 2B, a p ⁺ -type diffusion layer 4 is formed by applying a composition for forming a p ⁺ -type diffusion layer to a region of a part of the back surface, followed by heat treatment. On the p ⁺ -type diffusion layer 4, a heat treatment product 8 of a composition for forming a p ⁺ -type diffusion layer is formed.

Instead of the composition for forming a p-type diffusion layer, an aluminum electrode paste may be used. When an aluminum electrode paste is used, an aluminum electrode 8 is formed on the p ^& lt ^{; +} & gt ^; -type diffusion layer 4.

2 (c), the heat treatment product 8 or the aluminum electrode 8 of the composition for forming a p-type diffusion layer formed on the p ⁺ -type diffusion layer 4 is removed by a method such as etching .

2 (d), an electrode forming paste is selectively applied to the light receiving surface (front surface) and a part of the back surface of the semiconductor substrate 1, and then heat treatment is performed to form a layer on the light receiving surface The light receiving surface electrode 7 is formed, and the back surface electrode 5 is formed on the back surface. It is possible to form the n ⁺ -type diffusion layer 2 (see FIG. 2 (c)) through the antireflection film 3 by using the glass paste having the fire-proof property as the electrode forming paste to be coated on the light- The light receiving surface electrode 7 is formed, and an ohmic contact can be obtained.

In addition, since the p ⁺ -type diffusion layer 4 is previously formed in the region where the back electrode is formed, the electrode forming paste for forming the back electrode 5 is not limited to the aluminum electrode paste, An electrode paste capable of forming a low resistance electrode may be used. This makes it possible to further increase the power generation efficiency.

Then, as shown in FIG. 2 (e), a composition layer is formed by applying a composition for forming a passivation layer on a p-type layer on the back surface other than the region where the back electrode 5 is formed. Granting can be done, for example, by a method such as screen printing. The composition layer formed on the p-type layer is subjected to heat treatment (firing) to form the passivation layer 6. By forming the passivation layer 6 formed from the composition for forming the passivation layer of the present invention on the back p-type layer, a solar cell element having excellent power generation efficiency can be manufactured.

2E shows a method of forming a passivation layer only on the back surface of the semiconductor substrate 1, but in addition to the back surface of the p-type semiconductor substrate 1, a material for forming a passivation layer And a passivation layer may further be formed on the side (edge) of the p-type semiconductor substrate 1 by heat treatment (baking) (not shown). This makes it possible to manufacture a solar cell element with further improved power generation efficiency.

Further, the passivation layer may be formed by applying the composition for forming the passivation layer of the present invention only to the side surface of the semiconductor substrate without forming the passivation layer on the back surface portion, and then heat-treating (firing) the resultant. The effect of the composition for forming a passivation layer of the present invention is particularly large when it is used in a portion having many crystal defects such as a side surface.

2 (a) to 2 (e), the passivation layer is formed after the electrodes are formed. However, after the formation of the passivation layer, an electrode such as aluminum may be further formed in a desired region by vapor deposition or the like.

In the above-described embodiment, the case where the p-type semiconductor substrate having the n ⁺ -type diffusion layer formed on the light receiving surface is used. However, even when the n-type semiconductor substrate having the p ⁺ -type diffusion layer formed on the light receiving surface is used, A battery element can be manufactured. In such a case, an n ^& lt ^{; + &} gt ^; -type diffusion layer is formed on the back side.

The composition for forming the passivation layer can also be used for forming the passivation layer 6 on the light-receiving surface side or the back surface side of the back electrode type solar cell element in which the electrodes are disposed only on the back side as shown in Fig.

3, an n ^& lt ^{; + &} gt ^; -type diffusion layer 2 is formed in the vicinity of the surface of the p-type semiconductor substrate 1 on the light receiving surface side and a passivation layer 6 and an antireflection film 3 are formed on the surface. Respectively. As the antireflection film 3, a silicon nitride film, a titanium oxide film, or the like is known. Further, the passivation layer 6 is formed by applying the composition for forming the passivation layer of the present invention and subjecting it to heat treatment (firing). Since the passivation layer according to the present invention exhibits a good refractive index, it is believed that the power generation efficiency can be increased by being provided on the light receiving surface side.

On the back surface side of the p-type semiconductor substrate 1, the back electrode 5 is provided on each of the p ⁺ -type diffusion layer 4 and the n ⁺ -type diffusion layer 2, Layer 6 is provided.

The p ^& lt ^{; + &} gt ^; -type diffusion layer 4 can be formed by applying a composition for forming a p-type diffusion layer or an aluminum electrode paste to a desired region as described above and then heat-treating the p ⁺ -type diffusion layer 4. The n ^& lt ^{; + &} gt ^; -type diffusion layer 2 can be formed, for example, by applying a composition for forming an n ^& lt ^{; + &} gt ^; -type diffusion layer capable of forming an n ⁺ -type diffusion layer by a thermal diffusion process to a desired region and then performing heat treatment.

As the composition for forming the n-type diffusion layer, for example, there is a composition containing a donor element-containing substance and a glass component.

The back electrode 5 provided on the p ⁺ -type diffusion layer 4 and the n ⁺ -type diffusion layer 2 can be formed using a commonly used electrode formation paste such as a silver electrode paste.

In addition, if the electrode 5 is provided on the p ⁺ type diffusion layer 4 is, by using the aluminum electrode paste it is any of aluminum electrodes formed with the p ⁺ type diffusion layer 4.

The passivation layer 6 provided on the back surface can be formed by applying a composition for forming a passivation layer to a region where the back electrode 5 is not provided and by heat-treating (firing) the same.

The passivation layer 6 can be formed not only on the back surface but also on the side surface of the semiconductor substrate 1 (not shown).

In the back electrode type solar cell element as shown in Fig. 3, since there is no electrode on the light receiving surface side, the power generation efficiency is excellent. Further, since the passivation layer is formed in the region where the back electrode is not formed, the conversion efficiency is more excellent.

Although an example using a p-type semiconductor substrate as the semiconductor substrate has been described above, a solar cell element having excellent conversion efficiency can be manufactured in accordance with the above-described case even when an n-type semiconductor substrate is used. There is no limitation on the shape or size of the solar cell element, but it is generally preferable that the square is one side of 125 mm to 156 mm.

The solar cell has the solar cell element of the present invention and a wiring material disposed on the electrode of the solar cell element. The solar cell may also be connected to a plurality of solar cell elements through a wiring material such as a tap wire or the like and may be sealed with an encapsulating material as necessary.

The wiring material and the sealing material are not particularly limited and may be appropriately selected from those conventionally used in the art.

The size of the solar cell is not limited. The size of the solar cell is preferably 0.5 m ² to 3 m ² .

Example

Hereinafter, the present invention will be described concretely with reference to Examples, but the present invention is not limited to these Examples. Unless otherwise specified, "%" is based on mass.

&Lt; Example 1 >

(Preparation of composition 1 for forming a passivation layer)

5.00 g of ethyl cellulose (trade name: ETHOCEL 200 cps, manufactured by Nissin Kasei K.K.) and 95.02 g of terpineol (Nippon Terpene Chemical Co., Ltd.) were mixed and stirred at 150 ° C for 1 hour to prepare an ethylcellulose solution.

Next, 15.1 g of aluminum ethylacetoacetate diisopropylate (trade name: ALCH, manufactured by Kawaken Fine Chemicals Co., Ltd.), 5.1 g of niobium ethoxide (Wako Pure Chemical Industries, Ltd.), 0.35 g of titanium tetraisopropoxide (Manufactured by Wako Pure Chemical Industries, Ltd.), 35.2 g of the ethylcellulose solution and 30.2 g of terpineol (Terpen Chemical Co., Ltd.) were mixed to prepare a composition 1 for forming a passivation layer.

(Formation of Passivation Layer)

As a semiconductor substrate, a monocrystalline p-type silicon substrate whose surface is mirror-shaped (manufactured by Sumco, 50 mm by 50 mm in length and 625 μm in thickness) was used. The silicon substrate was immersed and washed in an RCA cleaning liquid (Kanto Kagaku Co., Ltd., trade name: Frontier Cleaner-A01) at 70 ° C for 5 minutes, and pretreated.

Then, on the silicon substrate pretreated with the above-obtained composition 1 for forming a passivation layer, the entire surface was subjected to a drying treatment at 150 캜 for 5 minutes by a screen printing method so as to have a thickness of 5 탆 after drying . Subsequently, the substrate was heat-treated (fired) at 700 ° C for 10 minutes and cooled at room temperature to prepare a substrate for evaluation.

The composition for forming a passivation layer and the evaluation substrate produced using the composition thus obtained were evaluated as follows. The evaluation results are shown in Table 1.

(Evaluation of Tic Consumption)

The shear viscosity of the composition 1 for forming a passivation layer prepared above was measured using a cone plate (diameter 50 mm, cone angle of 1 DEG) mounted on a rotary shear viscometer (Anton Paar, trade name: MCR301) immediately after preparation Under the conditions of a shear rate of 1.0 s ^-1 and 10 s ^-1 at a temperature of 25 ° C.

Shear viscosity (? ₂ ) of 35.0 Pa 占 퐏 under the conditions of a shear viscosity (? ₁ ) of 44.0 Pa 占 퐏 and a shear rate of 10 s ^-1 under a shear rate of 1.0 s ^-1 . The tic consumption (η ₁ / η ₂ ) was 1.3 when the shear viscosity was 1.0 s ^-1 and 10 s ^-1 .

(Evaluation of storage stability)

The shear viscosity of the composition 1 for forming a passivation layer prepared above was measured immediately after preparation (within 12 hours) and at 25 占 폚 for 30 days. The shear viscosity was measured at a shear rate of 1.0 s < ^-1 > at a temperature of 25 DEG C by mounting a cone plate (diameter 50 mm, cone angle of 1 DEG) on MCR301 (trade name, manufactured by AntonPaar).

The shear viscosity (? ₀ ) at 25 占 폚 immediately after the preparation was 44.0 Pa 占 퐏, and the shear viscosity? ₃₀ at 25 占 폚 after storage at 25 占 폚 for 30 days was 44.6 Pa 占 퐏.

The rate of change of the shear viscosity after storage at 25 DEG C for 30 days was calculated by the formula (B) and the storage stability was evaluated according to the following evaluation criteria.

(%) Of shear viscosity = (? _30- ? ₀ ) / (? ₀ ) 100 (B)

[Evaluation standard]

A: The rate of change in shear viscosity was less than 10%.

B: Rate of change of shear viscosity was 10% or more and less than 30%.

C: The rate of change in shear viscosity was 30% or more.

When the evaluation is A or B, it is good as a composition for forming a passivation layer.

(Measurement of effective life)

The effective lifetime (占 퐏) of the evaluation substrate obtained as described above was measured at room temperature (25 占 폚) using a lifetime measuring apparatus (WT-2000PVN, trade name; Respectively. The effective lifetime of the obtained area of the evaluation substrate to which the composition 1 for forming a passivation layer was applied was 300 mu s.

(Measurement of Thickness and Refractive Index of Passivation Layer)

The average thickness and the refractive index of the passivation layer on the evaluation substrate obtained above were measured using an interference film thickness gage (F20 Film Thickness Measurement System, manufactured by Philatel). The thickness of the passivation layer was 220 nm, and the refractive index was 1.71.

&Lt; Example 2 >

(Preparation of composition 2 for forming a passivation layer)

14.9 g of aluminum ethylacetoacetate diisopropylate, 9.8 g of titanium tetraisopropoxide, 35.1 g of the ethylcellulose solution and 29.7 g of terpineol were mixed to prepare a composition 2 for forming a passivation layer.

Evaluation was conducted in the same manner as in Example 1 except that the composition for forming a passivation layer 2 was used.

&Lt; Example 3 >

(Preparation of composition 3 for forming a passivation layer)

10.2 g of aluminum ethylacetoacetate diisopropylate, 10.2 g of zirconium ethoxide (manufactured by Wako Pure Chemical Industries, Ltd.), 35.1 g of the ethylcellulose solution and 30.4 g of terpineol were mixed to prepare a composition 3 for forming a passivation layer Lt; / RTI >

Evaluation was performed in the same manner as in Example 1 except that the composition for forming a passivation layer 3 was used.

(Preparation of composition 4 for forming a passivation layer)

15.2 g of aluminum ethylacetoacetate diisopropylate, 10.0 g of niobium ethoxide, 5.1 g of titanium ethoxide, 4.8 g of tetraethylorthosilicate (Wako Pure Chemical Industries, Ltd.), 34.7 g of the above ethylcellulose solution, 30.3 g were mixed to prepare a composition 4 for forming a passivation layer.

Evaluation was conducted in the same manner as in Example 1 except that the composition for forming a passivation layer 4 was used. The results are shown in Table 1.

&Lt; Example 5 >

(Preparation of composition 5 for forming a passivation layer)

14.9 g of aluminum ethylacetoacetate diisopropylate, 15.2 g of titanium ethoxide, 5.2 g of tetraethyl orthosilicate, 34.8 g of the ethylcellulose solution and 30.6 g of terpineol were mixed to prepare a composition 5 for forming a passivation layer Respectively.

Evaluation was carried out in the same manner as in Example 1 except that the composition for forming a passivation layer 5 was used.

&Lt; Example 6 >

(Preparation of composition 6 for forming a passivation layer)

15.0 g of aluminum ethylacetoacetate diisopropylate, 15.1 g of zirconium ethoxide, 5.1 g of tetraethyl orthosilicate, 35.3 g of the ethylcellulose solution and 29.6 g of terpineol were mixed to prepare a composition 6 for forming a passivation layer Respectively.

Evaluation was carried out in the same manner as in Example 1 except that the composition for forming a passivation layer 6 was used. The results are shown in Table 1.

&Lt; Example 7 >

(Preparation of composition 7 for forming a passivation layer)

15.1 g of aluminum ethylacetoacetate diisopropylate, 5.0 g of niobium ethoxide, 5.0 g of titanium isopropoxide, 35.2 g of isobornylcyclohexanol (trade name: TERESOLVE MTPH, manufactured by Nippon Terpene Chemical Co., Ltd.) And 14.9 g of pinone were mixed to prepare a composition 7 for forming a passivation layer.

Evaluation was conducted in the same manner as in Example 1 except that the composition for forming a passivation layer 7 was used. Then, the consumption of ticks is calculated as a ratio (η ₁ / η ₃₎ for the shear rate of 1.0 s ^-1 of shear viscosity (η ₁₎ and the shear viscosity (η ₃₎ when the shear rate of 1000 s ^-1 in the case Respectively.

&Lt; Example 8 >

(Preparation of composition 8 for forming a passivation layer)

15.2 g of aluminum ethylacetoacetate diisopropylate, 10.2 g of titanium isopropoxide, 34.8 g of isobornylcyclohexanol, and 15.2 g of terpineol were mixed to prepare a composition 8 for forming a passivation layer.

Evaluation was conducted in the same manner as in Example 1 except that the composition for forming a passivation layer 8 was used. The results are shown in Table 1. Then, the ticks were calculated consumption, as the ratio (η ₁ / η ₃₎ for the front end when the speed of 1.0 s ^-1 shear viscosity (η ₁₎ and the shear viscosity (η ₃₎ If the shear rate of 1000 s ^-1 .

&Lt; Example 9 >

(Preparation of composition 9 for forming a passivation layer)

14.8 g of aluminum ethylacetoacetate diisopropylate, 9.8 g of zirconium ethoxide, 35.5 g of isobornylcyclohexanol, and 15.2 g of terpineol were mixed to prepare a composition 9 for forming a passivation layer.

Evaluation was conducted in the same manner as in Example 1 except that the composition for forming a passivation layer 9 was used, and the results are shown in Table 1. Then, the ticks were calculated consumption, as the ratio (η ₁ / η ₃₎ for the front end when the speed of 1.0 s ^-1 shear viscosity (η ₁₎ and the shear viscosity (η ₃₎ If the shear rate of 1000 s ^-1 .

&Lt; Comparative Example 1 &

(Preparation of composition 10 for forming a passivation layer)

15.0 g of aluminum ethylacetoacetate diisopropylate, 35.0 g of the ethylcellulose solution and 30.2 g of terpineol were mixed to prepare a composition 10 for forming a passivation layer.

Evaluation was carried out in the same manner as in Example 1 except that the composition for forming a passivation layer 10 was used.

&Lt; Comparative Example 2 &

(Preparation of Passivation Layer Forming Composition 11)

15.1 g of aluminum ethyl acetoacetate diisopropylate, 34.9 g of isobornyl cyclohexanol and 15.2 g of terpineol were mixed to prepare a composition 11 for forming a passivation layer.

Evaluation was conducted in the same manner as in Example 1, except that the composition for forming a passivation layer 11 was used, and the results are shown in Table 1. Then, the ticks were calculated consumption, as the ratio (η ₁ / η ₃₎ for the front end when the speed of 1.0 s ^-1 shear viscosity (η ₁₎ and the shear viscosity (η ₃₎ If the shear rate of 1000 s ^-1 .

[Table 1]

From the above, it can be seen that by using the composition for forming a passivation layer of the present invention, a passivation layer having a high refractive index can be formed with an excellent passivation effect. It is also understood that the composition for forming a passivation layer of the present invention has excellent storage stability. Further, by using the composition for forming a passivation layer of the present invention, it can be seen that a passivation layer can be formed in a desired shape by a simple process.

Claims

An organoaluminum compound represented by the following general formula (I); And
At least one alkoxide compound selected from the group consisting of titanium alkoxide, zirconium alkoxide and silicon alkoxide
: &Lt; / RTI >
[Chemical Formula 1]

Wherein, in the general formula (I), R ¹ independently represents an alkyl group having 1 to 8 carbon atoms, n represents an integer of 0 to 3, X ² and X ³ each independently represent an oxygen atom or a methylene group, R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

The method according to claim 1,
And a niobium alkoxide.

3. The method of claim 2,
Wherein the niobium alkoxide is at least one selected from the group consisting of niobium ethoxide, niobium isopropoxide, niobium n-propoxide, niobium n-butoxide and niobium phenoxide.

4. The method according to any one of claims 1 to 3,
Wherein the alkoxide compound comprises at least the titanium alkoxide, and the titanium alkoxide is at least one compound selected from the group consisting of titanium methoxide, titanium ethoxide, titanium isopropoxide, titanium n-propoxide, titanium n-butoxide, Wherein the passivation layer is at least one selected from the group consisting of butoxide, titanium isobutoxide, titanium (diisopropoxide) bis (acetylacetonate) and titanium (tetrakis (2-ethyl-1-hexanolate) / RTI >

5. The method according to any one of claims 1 to 4,
Wherein the alkoxide compound comprises at least the zirconium alkoxide, and the zirconium alkoxide is at least one selected from the group consisting of zirconium ethoxide, zirconium isopropoxide, zirconium n-propoxide, zirconium n-butoxide, zirconium tert- Wherein the composition is at least one selected from the group consisting of acetylacetone, zirconium trifluoroacetylacetonate, and zirconium hexafluoroacetylacetonate.

6. The method according to any one of claims 1 to 5,
Wherein the alkoxide compound includes at least the silicon alkoxide, and the silicon alkoxide is a silicon alkoxide represented by the following general formula (II):
(R ⁵ O) _(4-m) SiR ⁶ _m (II)
[Wherein, in the general formula (II), R ⁵ and R ⁶ each independently represent an alkyl group having 1 to 8 carbon atoms, and m represents an integer of 0 to 3].

7. The method according to any one of claims 1 to 6,
A composition for forming a passivation layer further comprising a resin.

8. The method according to any one of claims 1 to 7,
A composition for forming a passivation layer further comprising a compound represented by the following general formula (III):
(2)

.

A semiconductor substrate; And
A passivation layer, which is a heat treatment of the composition for forming a passivation layer according to any one of claims 1 to 8, which is provided on an entire surface or a part of the semiconductor substrate,
Wherein the passivation layer is formed on the semiconductor substrate.

9. A method of manufacturing a semiconductor device, comprising the steps of: providing a composition for forming a passivation layer according to any one of claims 1 to 8 on an entire surface or a part of a semiconductor substrate to form a composition layer; And
A step of heat-treating the composition layer to form a passivation layer
And forming a passivation layer on the semiconductor substrate.

a semiconductor substrate in which a p-type layer and an n-type layer are pn-bonded;
A passivation layer which is a heat treatment product of the composition for forming a passivation layer according to any one of claims 1 to 8, which is provided on an entire surface or a part of the semiconductor substrate; And
An electrode disposed on at least one layer selected from the group consisting of the p-type layer and the n-type layer of the semiconductor substrate
.

at least a part of a surface of the semiconductor substrate having a pn junction formed by bonding a p-type layer and an n-type layer and having an electrode on at least one layer selected from the group consisting of the p-type layer and the n-type layer, 8. A method for manufacturing a passivation layer, comprising: forming a composition layer by applying the composition for forming a passivation layer according to any one of claims 1 to 8; And
A step of heat-treating the composition layer to form a passivation layer
Wherein the solar cell is a solar cell.

A solar cell element according to claim 11; And
A wiring material disposed on the electrode of the solar cell element
&Lt; / RTI >