CN101467498A - Shower plate, method for manufacturing the shower plate, plasma processing apparatus using the shower plate, plasma processing method and electronic device manufacturing method - Google Patents

Abstract

Provided is a shower plate which can completely prevent generation of plasma reverse flow or ignition of plasma excitation gas at a vertical hole section for more efficient plasma excitation. A shower plate (105) is arranged in a processing chamber (102) in a plasma processing apparatus, and discharges plasma excitation gas for generating plasma in the processing chamber (102). A porous gas communicating body (114) having pores communicating in a gas communicating direction is mounted on a vertical hole (112) to be a discharge path for the plasma excitation gas. The pore diameter of an overflow path in a gas communicating path formed by the communicating pores of the porous gas communicating body (114) is 10[mu]m or less.

Description

Shower plate and manufacture method thereof and used the manufacture method of its plasma processing apparatus, processing method and electronic installation

Technical field

The present invention relates to use at plasma processing apparatus, particularly use in microwave plasma processing apparatus shower plate with and manufacture method and used the manufacture method of plasma processing apparatus, method of plasma processing and the electronic installation of this shower plate.

Background technology

Plasma treatment operation and plasma processing apparatus are indispensable technology for the high-resolution flat display apparatus of making in recent years that has the long ultra micro refinement semiconductor device of the following grid of 0.1 μ m or 0.1 μ m, comprises liquid crystal indicator for manufacturing that is known as so-called deep-submicron element or dark inferior 1/4th microns elements.

As the plasma processing apparatus that is used to make semiconductor device, liquid crystal indicator, from just used various plasma excitation modes in the past always, particularly use parallel plate-type high frequency pumping plasma processing apparatus or inductance coupling high type plasma processing apparatus usually.But because the plasma that above-mentioned in the past plasma processing apparatus forms is inhomogeneous, and electron-dense zone is defined, therefore have be difficult to bigger processing speed, be the problem that productivity ratio is handled uniformly to the whole face of processed substrate.This problem is particularly more serious when handling the situation of larger-diameter substrate.And in above-mentioned plasma processing apparatus in the past, exist because of electron temperature is high to make the semiconductor element that is formed on the processed substrate damage, cause serious some problems in essence such as metallic pollution on the process chamber wall because of being splashed in addition.Therefore in plasma processing apparatus in the past, be difficult to satisfy always and further improve semiconductor device, the miniaturization of liquid crystal indicator and the strict demand of boosting productivity.

At the problems referred to above, proposed not use D.C. magnetic field in the past and be to use microwave plasma processing apparatus by the high-density plasma of microwave electric field excitation.For example, the plasma processing apparatus (for example with reference to patent documentation 1) of following structure has been proposed:, thereby utilize the indoor gas excitation plasma of this microwave electric field ionization process from plane antenna (radial line slot antenna) radiated microwaves in process chamber with many slots arranging in order to produce even microwave.The higher ion volume density is realized on the broad regions ground that the microwave plasma that utilization has been encouraged by this method can spread all under the antenna, thereby can carry out uniform plasma treatment at short notice.And because the microwave plasma that forms with this method is to utilize the microwave excitation plasma, so electron temperature is lower, can avoid damage, the metallic pollution of processed substrate.And, owing to can also be easy on large-area substrate the uniform plasma of excitation, therefore also be easy to corresponding to the semiconductor device that has used the heavy caliber semiconductor substrate manufacturing process, make large-scale liquid crystal indicator.

In above-mentioned plasma processing apparatus, usually, have the shower plate of a plurality of vertical holes as the gas discharge path in order in process chamber, to supply with plasma excitation gas equably, to use.But, use shower plate to make sometimes to be formed on the plasma under the shower plate in the vertical hole of shower plate, adverse current to take place.When plasma in vertical hole adverse current takes place, have and paradoxical discharge, gas take place pile up, be used to encourage the efficiency of transmission of the microwave of plasma, the problem of decrease in yield.

Prevent the method for this plasma as being used to, proposed to improve the structure of shower plate mostly to vertical hole adverse current.

For example, it is effective disclosing 2 times that the aperture that will indulge the gas discharge hole of hole front end is set as less than lining (sheath) thickness that is formed on the plasma under the shower plate in patent documentation 2.But the aperture that just reduces gas discharge hole also can fully not prevent the adverse current of plasma.Particularly, for reduce damage, improve the purpose of processing speed and desire with plasma density from the past 10 ¹²Cm ^-3Degree brings up to 10 ¹³Cm ^-3Therefore just during degree, the adverse current of plasma becomes obviously, and the aperture of control gaseous tap can not prevent the adverse current of plasma.In addition, be difficult to utilize hole processing on the shower plate main body, to form the gas discharge hole in fine aperture, on processability, also have problems.

In addition, the shower plate that in patent documentation 3, has also proposed to use the porous ceramic sintered body by gas permeability to constitute.The wall of many pores of this method desire utilization formation porous ceramic sintered body prevents the adverse current of plasma.

But, this shower plate that constitutes by the common porous ceramic sintered body of sintering under normal temperature, normal pressure, the size of its hole diameter has very big deviation from a few μ m up to tens μ m degree, and at maximum crystalline particle diameter greatly to about the 20 μ m, tissue odds is even, therefore the problem that has the surface difference, in addition, in the time will being made as the porous ceramic sintered body with the contacted face of plasma, have that effective surface area increases, the electronics of plasma, ion again in conjunction with increase, the problem of the power efficiency step-down of plasma excitation.At this, following structure is also disclosed in the above-mentioned patent documentation 3: replace utilizing the porous ceramic sintered body constitute shower plate integrally, on the shower plate that the aluminium oxide by densification constitutes, forms the peristome of gas discharge usefulness, at the common porous ceramic sintered body that is installed in sintering under normal temperature, the normal pressure on this peristome, discharge gas by this porous ceramic sintered body.But,, so can not solve because of the surface difference and cause the problems referred to above of taking place because this structure also is to use the common porous ceramic sintered body of sintering under normal temperature, normal pressure.

And the application's applicant has at first proposed to prevent by the diameter dimension of adjusting gas discharge hole the method for the adverse current of plasma in patent documentation 4, rather than improves the structure of shower plate.Promptly, the diameter dimension of gas discharge hole is set as less than 0.1～0.3mm, and the tolerance of its diameter dimension is set as ± 0.002mm is with interior precision, thus prevent the adverse current of plasma, and eliminated the deviation of gas discharge rate.

But increasing with plasma density in reality is 10 ¹³Cm ^-3Condition under find when in microwave plasma processing apparatus, using this shower plate, as shown in figure 21, or because of plasma space 602 and with vertical hole 603 that this space 602 is connected in adverse current takes place or produced Sandy variable color part because of plasma excitation catches fire in the part in space 602 and vertical hole 603 with gas, this space 602 is formed between shower plate main body 600 and the cover plate 601, is used for filling plasma excitation gas.

Patent documentation 1: Japanese kokai publication hei 9-63793 communique

Patent documentation 2: TOHKEMY 2005-33167 communique

Patent documentation 3: TOHKEMY 2004-39972 communique

Patent documentation 4: the international brochure that discloses No. 06/112392

Summary of the invention

Thereby the problem that desire of the present invention solves is to provide a kind of and can prevents more completely that plasma generation adverse current or the vertical hole portion plasma excitation in dividing from catching fire with gas and can encourage the shower plate of plasma efficiently.

Shower plate of the present invention is discharged plasma excitation gas in order to make generation plasma in the plasma processing apparatus, wherein, install in the vertical hole of the discharge path of gas and have forming plasma excitation at the porous gas flow body of the coconnected pore of gas communication direction and ceramic component with suitable a plurality of gas discharge holes, and the hole diameter of the narrow road in the gas flowing path that will be formed by the pore of the connection of this porous gas flow body is located at below the 10 μ m, thereby can prevent the adverse current of plasma, and can in plasma processing apparatus, discharge plasma excitation gas in zero deflection ground, produce uniform plasma.

In addition, the length by making gas discharge hole can sharply reduce the adverse current of plasma greater than the length of the mean free path of the electronics in the plasma processing apparatus.

In addition, implement chamfer machining by the bight that the gas that is opened in the vertical hole on the shower plate is imported side, can also prevent microwave in the above-mentioned bight concentrate along with electric field and discharge so plasma excitation with the phenomenon of catching fire of gas.

As mentioned above, be located at below the 10 μ m, by hole diameter even plasma density is brought up to 10 with the narrow road of porous gas flow body ¹³Cm ^-3Degree also can prevent the adverse current of plasma.Promptly, in this porous gas flow body, can guarantee the circulation of gas by the pore that is communicated with, but this gas flowing path is Z word shape complications, and between the narrow road that wherein exists below the 10 μ m, below the preferred 5 μ m.Relative therewith, has straightline propagation owing to constitute electronics, the ion of plasma, even therefore plasma continues adverse current in the porous gas flow body, most of meeting collision air vent wall, and the narrow road portion of all plasmas below 10 μ m of pore bumps, thereby can stop the further adverse current of plasma.

At this, disclosing in the above-mentioned patent documentation 3 and use the porous ceramic sintered body of aeration on shower plate is the porous gas flow body that has at the coconnected pore of gas communication direction.But, because the maximum crystalline particle diameter of the common porous ceramic sintered body that patent documentation 3 is used is more than 20 μ m, and the hole diameter foot of the narrow road in the gas flowing path that is formed by the pore that is communicated with is greater than 10 μ m, so plasma density is being brought up to 10 ¹³Cm ^-3Can not prevent the adverse current of plasma under the condition of degree fully.In addition, as mentioned above, in the bigger common porous ceramic sintered body of crystalline particle diameter, because the cause that surface is poor, its effective surface area is big, exist the electronics of plasma, the combination again of ion to increase the problem that the power efficiency of plasma excitation reduces.

At the problems referred to above, in the present invention, with respect to plasma density is brought up to 10 ¹³Cm ^-3Situation under 2 times (the 20 μ m) of lining thickness 0.01mm of plasma, hole diameter with narrow road is located at below the 10 μ m as mentioned above, thereby can prevent the adverse current of plasma reliably, and it is as described below, by using the porous gas flow body that constitutes by the fine and highly purified ceramic sintered bodies of crystalline particle, surface can be improved, thereby the problem that the increase of the combination again of electronics because of plasma, ion causes the power efficiency of plasma excitation to reduce can be solved.

Promptly, as the porous gas flow body, by the high-purity that does not contain the impurity that increases dielectric loss and to have a porous ceramic sintered body of the aeration that the ceramic sintered bodies of fine crystal tissue constitutes outstanding at aspects such as dielectric loss, intensity, can enumerate the grain growth inhibitor, the Y that for example are combined with high-purity alpha-alumina and trace ₂O ₃And alumina series sintered body, AlN sintered body, the SiO of mullite etc. ₂Sintered body, mullite sintered body, SiN ₄Sintered body, SiAlON sintered body etc.The size of preferred its hole diameter is less than 2 times of the lining thickness that is formed on the plasma under the shower plate.In addition, preferred crystalline particle diameter is fine, even tissue, agonic sintered body.Particularly, adopt the dielectric loss of the porous ceramic sintered body that constitutes by the alumina series pottery 1 * 10 ^-3Below, more preferably 5 * 10 ^-4Below and maximum crystalline particle diameter below the 15 μ m, more preferably below the 10 μ m and also the average crystallite particle diameter below the 10 μ m, more preferably below the 5 μ m and in the scope of the porosity 20～75%, average pore diameter below the 10 μ m and maximum hole diameter below the 75 μ m, the material of hole diameter below 10 μ m of the narrow road of gas flowing path be the porous gas flow body.And, be located at more than the 30MPa by intensity (bending strength) the porous ceramic sintered body, can make the surface roughness (Ra) of the grinding face except pore part is below the 1.5 μ m, therefore can eliminate the increase of variation, effective surface area of the surface of the porous ceramic sintered body of following in the past and the disadvantage that produces.As an example, adopt the highly purified Al more than 99.9% ₂O ₃Micropowder is than being easier to make the porous ceramic sintered body with aforesaid many characteristics.By using such porous ceramic sintered body can prevent the adverse current of plasma more reliably.

The gas that above-mentioned porous gas flow body can be configured in the gas discharge hole of the gas discharge side of being located at vertical hole imports on the leading section in side or vertical hole.

At this, when the gas that the porous gas flow body is located at gas discharge hole imports side, because the porous gas flow body does not directly contact with plasma and also can not influence the flatness of shower plate lower surface, therefore can solve the problem of power efficiency decline of the plasma excitation that increase caused of the combination again of electronics because of plasma, ion.By plasma excitation was imported in the porous gas flow body before importing gas discharge hole with gas, can make the plasma excitation in each vertical hole with many characteristic homogenizing such as the pressure of gas, flow velocitys.Then, owing to afterwards plasma excitation being discharged from a plurality of gas discharge holes with gas, therefore can keep with gas flow zero deflection ground under the state constant and even discharge on the wide face of shower plate plasma excitation being discharged in the plasma processing apparatus with gas at the plasma excitation that makes each gas discharge hole.Thereby, can under shower plate, produce uniform plasma effectively.In other words, make the porous gas flow body with buffering effect of plasma excitation by import the side configuration at the gas of gas discharge hole with many characteristic homogenizing such as the pressure of gas, flow velocitys, can eliminate the flow velocity of the gas of discharging and the deviation of flow, the homogenizing of the plasma of seeking to produce from gas discharge hole.Then, utilize as described above have an advantage that can under shower plate, produce uniform plasma effectively and import the porous gas flow body that the ceramic sintered bodies with fine crystal tissue of side constitutes by the gas that is configured in gas discharge hole, can prevent the gas importing side generation adverse current of plasma in vertical hole.

Import at the gas that the porous gas flow body is configured in gas discharge hole under the situation of side, preferably import side and the gas bigger than gas discharge hole aperture is set continuously passes through the hole at the gas of porous gas flow body.This gas forms following path by the hole, promptly, plasma excitation is used the path on the lead-in path guiding porous gas circulation side of gas from the plasma excitation that is made of the cross-drilled hole that for example is located on the shower plate with gas, make the aperture of its aperture greater than gas discharge hole, thereby can be easy to plasma excitation is used gas channeling porous gas circulation side, thereby can improve whole gas on-state rate.In addition, owing to can reduce the fluid resistance of gas, so pressure loss is few, can set the supply pressure of gas lower, thereby can save the energy.

In the present invention, also the porous gas flow body can be installed on the leading section at least in vertical hole.Like this, in the time of on the leading section at least that the porous gas flow body is installed in vertical hole, because plasma excitation gas is discharged on the whole surface from the porous gas flow body, therefore can make many characteristic homogenizing such as the plasma excitation that the is discharged from pressure of gas, flow velocity.Thereby, but plasma excitation gas is evenly discharged on zero deflection ground, produces the uniform plasma of no turbulent flow phenomenon under shower plate.

In addition in this case, the upper surface of porous gas flow body and lower surface can form parallel plane in plasma processing apparatus, but preferably both all bend to convex surface shape or concave curved surface shape, the shape of convex spherical shell or concavity spherical shell in other words.By being arranged to crooked shape like this, can absorb the thermal expansion when using, the stress that contraction causes by distortion (deflection), the crackle etc. that can prevent the porous gas flow body and the shower plate of porous gas flow body is installed.In addition, form in plasma processing apparatus on two surfaces under the situation of convex surface shape,, therefore can produce more uniform plasma owing to can discharge plasma excitation gas to wideer scope.

And the periphery except upper surface and lower surface of porous gas flow body can be formed by the compact substance ceramic layer.In the time of on the vertical hole that the porous gas flow body is installed in shower plate, owing to the periphery of porous gas flow body may be broken particle is come off, therefore should be noted that, but be set as the compact substance ceramic layer by periphery with the porous gas flow body, can make periphery be difficult to break, thereby the raising operability, and can prevent to cause producing pollutant because of particle comes off.

Can utilize chimeric or sinter bonded above-mentioned porous gas flow body to be installed on the leading section in vertical hole of shower plate.Porous gas flow body and shower plate be under the state of sintered body chimeric they the time, the outside dimension that makes the porous gas flow body with respect to the internal diameter size in the vertical hole of shower plate be 0～-utilize that hot pressing is gone into, shrink-fit or be pressed into and make both chimeric 0.002mm.

Perhaps, after in the vertical hole that outer peripheral face is coated with the shower plate after the porous gas flow body of stable on heating pottery with adhesive is encased in sintering, carry out sintering with the temperature more than 400 ℃, thereby also can under bonding securely state, the porous gas flow body be installed in the shower plate.

In addition, also can the porous gas flow body be installed in the shower plate, simultaneously they be carried out sintering afterwards in the stage before porous gas flow body and shower plate all are in sintering.Promptly, about the porous gas flow body, be to carry out moulding and be processed into the powder compact that obtains after the regulation shape, the degreasing body of powder compact or the stage of presintering body or sintered body at material powder to the porous gas flow body, about shower plate, be to carry out moulding and be processed to form the green compact body in vertical hole, the degreasing body of green compact body or the stage of presintering body at material powder to shower plate, the porous gas flow body is installed in the vertical hole of shower plate, afterwards simultaneously sintering both.In this case, the degreasing after the adjustment moulding conditioned disjunction, the condition of presintering make that the shrinkage of each member when carrying out sintering at the same time is substantially the same, and fastening force acts on the porous gas flow body at least.Like this, by the stage before sintering install and after the while sintering, can the porous gas flow body be fixed in the vertical hole of shower plate reliably.

And in the present invention, also can use the ceramic component that will offer a plurality of gas discharge holes to be installed in structure in the vertical hole that is opened on the shower plate.Promptly, with gas discharge hole be formed on the separate ceramic component of shower plate on, this ceramic component is installed in the vertical hole that is opened on the shower plate.By adopting such structure, compare the situation of utilizing hole processing on shower plate, to form gas discharge hole, can be easy to form fine and long gas discharge hole.In addition, the ceramic component that offers gas discharge hole can form by injection-molded moulding, extrusion modling or special cast molding etc.As the size of gas discharge hole, preferably make its aperture be formed at shower plate under below 2 times of lining thickness of plasma, and make the mean free path of its length greater than the electronics in the process chamber.By fine and long gas discharge hole is set like this, prevent the adverse current of plasma more reliably thereby can interosculate with the effect that the gas that is located at gas discharge hole imports the porous gas flow body of side.

Be installed in concrete mode in each vertical hole as the member that will be provided with the above-mentioned gas tap, the gas that preferably utilizes above-mentioned member to stop up each vertical hole is discharged the mode of side.In this case, the gas discharge side constriction that preferably will indulge the hole must be narrower than gas and import side, is located at above-mentioned member on this narrow and makes it import side along gas and extend.In addition, also the porous gas flow body can be imported side with the gas that the mode that is connected with the gas discharge hole of above-mentioned member is configured in vertical hole.In such structure, preferably make the mean free path of the length of gas discharge hole greater than the electronics in the plasma processing apparatus, the aperture that makes gas discharge hole is below 2 times of lining thickness that are formed at the plasma under the shower plate, and the aperture that makes the pore of porous matter flow body is to be formed at below the lining thickness of the plasma under the shower plate.

And, in addition in forming the vertical hole portion branch of plasma excitation with the shower plate of the gas flow path part of gas, the electric field of microwave concentrates on the bight that gas imports side, therefore can prevent that by above-mentioned bight being implemented chamfer machining electric field is concentrated, thereby can prevent the spontaneous phenomenon of catching fire that is plasma excitation with gas of plasma.

Then, adopt above-mentioned shower plate of the present invention, plasma excitation can be supplied in the plasma processing apparatus with gas, the plasma excitation that utilizes microwave excitation to supply with produces plasma with gas, use this plasma substrate to be carried out processing such as oxidation, nitrogenize, oxynitriding, CVD, etching, plasma irradiating.

Adopt the present invention, can prevent plasma adverse current in the vertical hole of the discharge path that forms plasma excitation usefulness gas of shower plate, thereby can suppress that shower plate inner paradoxical discharge takes place, gas is piled up, so can prevent to be used to encourage the through-put power of the microwave of plasma, the decline of rate of finished products.

In addition, evenly discharge plasma excitation gas owing to can not influence with the flatness of contacted of plasma and zero deflection ground, so can be evenly and encourage plasma efficiently.

Description of drawings

Fig. 1 represents the first embodiment of the present invention.

Fig. 2 represents to overlook the cross-drilled hole of shower plate shown in Figure 1 and the configuration in vertical hole.

Fig. 3 represents the cross-drilled hole of shower plate shown in Figure 1 and the configuration in vertical hole.

Fig. 4 represents the vertical hole of shower plate shown in Figure 1 in detail.

Fig. 5 represents the second embodiment of the present invention.

Fig. 6 represents the configuration of shower plate and cover plate shown in Figure 5.

Fig. 7 represents the vertical hole of shower plate shown in Figure 5 in detail.

Fig. 8 represents to be installed in the preferred ideal structure of the ceramic component in the vertical hole of shower plate shown in Figure 5.

Fig. 9 is illustrated in the example that is provided with the porous ceramic sintered body in the vertical hole of shower plate shown in Figure 7.

Figure 10 represents the third embodiment of the present invention.

Figure 11 represents the vertical hole of shower plate shown in Figure 10 in detail.

Figure 12 represents the fourth embodiment of the present invention.

Figure 13 represents to overlook the cross-drilled hole of shower plate shown in Figure 12 and the configuration in vertical hole.

Figure 14 represents the cross-drilled hole of shower plate shown in Figure 12 and the configuration in vertical hole.

Figure 15 represents the vertical hole of shower plate shown in Figure 12 in detail.

Figure 16 represents to have the example of the ceramic component of gas stream through hole or the gas importing side that other porous ceramic sintered body is arranged on the porous ceramic sintered body on the vertical hole leading section that is installed on shower plate.

Figure 17 represents other installation example of porous ceramic sintered body.

Figure 18 represents the fifth embodiment of the present invention.

Figure 19 represents the configuration of shower plate and cover plate shown in Figure 180.

Figure 20 represents the vertical hole of shower plate shown in Figure 180 in detail.

Figure 21 represents shower plate in the past.

Description of reference numerals

101, exhaust outlet; 102, process chamber; 103, processed substrate; 104, keep platform; 105, shower plate; 106, the O RunddichtringO of sealing usefulness; 107, wall; 108, the O RunddichtringO of sealing usefulness; 109, annulus; 110, gas introduction port; 111, cross-drilled hole; 112, vertical hole; 112a, the first vertical hole; 112b, the second vertical hole; 113, ceramic component; 113a, gas discharge hole; 114, porous ceramic sintered body (porous gas flow body); 115, aperture plate; 116, slow-wave plate; 117, coaxial waveguide; 118, metallic plate; 119, cooling stream; 120, lower floor's shower plate; 120a, gas flow path; 120b, nozzle; 120c, peristome; 121, handle gas supply port; 122, RF power supply; 200, vertical hole; 200a, the first vertical hole; 200b, the second vertical hole; 201, shower plate; 202, cover plate; 203, the O RunddichtringO of sealing usefulness; 204, gas supply hole; 205, space; 206, ceramic component; 206a, gas discharge hole; 207, porous ceramic sintered body (porous gas flow body); 208, chamfer machining; 300, vertical hole; 300a, gas discharge hole; 300b, hole; 301, shower plate; 302, porous ceramic sintered body (porous gas flow body); 303, chamfer machining; 400, shower plate; 401, cross-drilled hole; 402, vertical hole; 402a, the first vertical hole; 402b, the second vertical hole; 403, porous ceramic sintered body (porous gas flow body); 404, ceramic component; 404a, gas stream through hole; 500, vertical hole; 501, shower plate; 502, porous ceramic sintered body (porous gas flow body); 502a, compact substance ceramic layer; 502b, porous matter portion.

Embodiment

Below, according to embodiment embodiments of the present invention are described.

Embodiment 1

Fig. 1 represents the first embodiment of the present invention.With reference to Fig. 1, the expression microwave plasma processing apparatus.Illustrated microwave plasma processing apparatus has the process chamber 102 that carries out exhaust by a plurality of exhaust outlets 101, disposes the maintenance platform 104 that is used to keep processed substrate 103 in process chamber 102.For equably to carrying out exhaust in the process chamber 102, process chamber 102 keep platform 104 around stipulate out ring-type the space, a plurality of exhaust outlets 101 are in the mode that is connected with the space uniformly-spaced, promptly arrange with respect to processed substrate 103 axisymmetrically.Utilize the arrangement of this exhaust outlet 101, can carry out exhaust to process chamber 102 equably by exhaust outlet 101.

On the top of process chamber 102 by the O RunddichtringO 106 of sealing usefulness on corresponding to the position that keeps the processed substrate 103 on the platform 104, as the part of the outer wall of process chamber 102 be equipped with as diameter be 408mm, relative dielectric constant be 9.8 and low microwave dielectric loss (dielectric loss is 1 * 10 ^-3Below, more preferably 5 * 10 ^-4Below) dielectric shower plate 105 that constitutes by aluminium oxide.In addition, constituting on the wall 107 of process chamber 102, on the position corresponding, be provided with the annulus 109 that the side by the O RunddichtringO 108 of 2 sealing usefulness and shower plate 105 fences up with the side of shower plate 105.Annulus 109 be used to import the gas introduction port 110 of plasma excitation and be connected with gas.

On the other hand, on the side of shower plate 105, laterally offer many cross-drilled holes 111 of diameter 1mm towards the center position of shower plate 105.Simultaneously, the earthing that links to each other with this cross-drilled hole 111 offers many (230) being communicated with process chamber 102 vertical hole 112.

Fig. 2 represents to overlook the cross-drilled hole 111 of shower plate 105 and the configuration in vertical hole 112.Fig. 3 is the schematic perspective view of the configuration in expression cross-drilled hole 111 and vertical hole 112.In addition, Fig. 4 represents the detailed construction in vertical hole 112.Vertical hole 112 is made of the first vertical hole 112a of the diameter 10mm that is located at process chamber 102 sides, dark 10mm and the second vertical hole 112b of diameter 1mm that further is located at the place ahead (gas importing side) of the first vertical hole 112a, is connected with cross-drilled hole 111.And, on the first vertical hole 112a, ceramic component 113 and the gas sintered body 114 of porous ceramic are installed successively from the observation of process chamber 102 sides; Above-mentioned ceramic component 113 high 5mm are made of aluminium oxide extrusion modling product, offer the gas discharge hole 113a of a plurality of diameter 50 μ m; The gas sintered body 114 of above-mentioned porous ceramic is the cylindric of diameter 10mm, high 5mm, has at the coconnected pore of gas communication direction.

At this, the gas of porous ceramic sintered body 114 imports the second vertical hole 112b of side corresponding to technical scheme 5 of the present invention described " gas passes through the hole ".

Represent the method for plasma excitation with reference to Fig. 1 with the gas channeling process chamber.The plasma excitation that is imported by gas introduction port 110 is imported into annulus 109 with gas, and is imported in the process chamber 102 via cross-drilled hole 111, vertical hole 112 final gas discharge hole 113a on the fore-end that is located at vertical hole 112.

Be provided with the aperture plate 115 that is used for radial line slot antenna radiated microwaves, that offer many slits at the upper surface of shower plate 105, be used to make slow-wave plate 116 that microwave radially propagates and the coaxial waveguide 117 that is used for microwave is imported antenna.In addition, slow-wave plate 116 is by aperture plate 115 and metallic plate 118 clampings.On metallic plate 118, be provided with cooling stream 119.

In this structure, utilize the plasma excitation gas of supplying with from shower plate 105 from the ionized of aperture plate 115 radiation, thereby several millimeters zone produces high-density plasma under shower plate 105.The plasma that produces is owing to diffusion arrives processed substrate 103.Except importing plasma excitation,, also can import oxygen, ammonia from shower plate 105 as the gas that produces free radical energetically with the gas.

In illustrated plasma processing apparatus, in process chamber 102, between shower plate 105 and the processed substrate 103, dispose the lower floor's shower plate 120 that constitutes by conductors such as aluminium, stainless steels.This lower floor's shower plate 120 has a plurality of gas flow path 120a of the processed substrate 103 in the processing gas channeling process chamber 102 that the body supply port 121 that is used for regulating the flow of vital energy getting along alone supplies with, and utilizes many nozzle 120b being formed on the face corresponding with the processed substrate 103 of gas flow path 120a, will handle gas and be discharged to space between lower floor's shower plate 120 and the processed substrate 103.At this, as handling gas, carrying out Plasma-Enhance Chemical Vapor Deposition (PECVD, the plasma-reinforced chemical vapour deposition) under the situation of Chu Liing, under the situation of the film that forms silicon system, import silane gas, disilane gas, under the situation that forms film having low dielectric constant, import C ₅F ₈Gas.In addition, as handling gas, also can be the CVD (chemical vapor deposition) that has imported organic metal gas.In addition, carrying out under the situation that Reactive Ion Etching (RIE, reactive ion etching) handles, carrying out under the etched situation of silicon oxide layer, import C ₅F ₈G﹠O under the situation of etching metal film, silicon, imports chlorine, HBr gas for handling gas for handling gas.When carrying out etching, needing under the situation of ion energy, by capacitor RF power supply 122 is connected with the electrode that is located at above-mentioned maintenance platform 104 inside, apply RF electric power, produce automatic bias voltage on the processed substrate 103 thereby make.The gaseous species of the processing gas that flows is not limited to above-mentioned gas but sets mobile gas, pressure according to handling.

Between the adjacent gas flow path 120a on lower floor's shower plate 120, form the peristome 120c of following degree size, that is, the size of this peristome 120c make utilize on the top of lower floor's shower plate 120 microwave excited plasma efficiently by and be diffused in the space between processed substrate 103 and the lower floor's shower plate 120.

In addition, owing to being exposed to the hot-fluid that flows to shower plate 105 in the high-density plasma, can utilize to flow into cooling via aperture plate 115, slow-wave plate 116 and metallic plate 118 and carry out heat extraction with the cold-producing medium of the water of stream 119 etc.

With reference to Fig. 4, the diameter of offering a plurality of gas discharge hole 113a on the columned ceramic component 113 that is made of alumina material in the present embodiment is 50 μ m.This numerical value is less than as 10 ¹²Cm ^-32 times of 40 μ m of lining thickness of high-density plasma, but greater than as 10 ¹³Cm ^-32 times of 10 μ m of lining thickness of high-density plasma.

At this, ceramic component 113 utilizes by the high-purity Al more than 99.95% ₂O ₃Constitute, dielectric loss is 1 * 10 ^-3Following material forms.

In addition, be formed on the contacted body surface of plasma on the thickness d of lining can try to achieve with following formula.

Formula 1

$d=0.606{\mathrm{\λ}}_D{\left(\frac{{2V}_0}{T_e}\right)}^{3/4}$

At this, V ₀Be the potential difference (unit is V) of plasma and object, T _eBe electron temperature (unit is eV), λ _DIt is the Debye length that available following formula is tried to achieve.

Formula 2

${\text{\λ}}_D=\sqrt{\frac{{\mathrm{\ϵ}}_{0}k{T}_e}{n_e{e}^2}}=7.43\×{10}^3\sqrt{\frac{T_e\left[\mathrm{eV}\right]}{n_e\left[m^{-3}\right]}}---\left[m\right]$

At this, ε ₀Be the permeability of vacuum, k is that Bohr is grown graceful constant, n _eIt is plasma electron density.

As shown in table 1, because Debye length descends when plasma electron density rises, therefore this viewpoint of adverse current from preventing plasma we can say that the aperture of preferred gas tap 113a is littler.

Table 1

T _e＝2eV，V _O＝12V

Plasma density (cm -3)	Debye length (mm)	Lining thickness (mm)
			10 13	0.003	0.01
10 12	0.011	0.04
			10 11	0.033	0.13
10 10	0.105	0.41

And, the length of gas discharge hole 113a is made as than the average distance before the electronics generation scattering, is the long length of mean free path, thereby can sharply reduce the adverse current of plasma.The mean free path of table 2 expression electronics.Mean free path and pressure are inversely proportional to, and are 4mm when 0.1Torr.In fact, because that the gas of gas discharge hole 113a imports the pressure of side is higher, so mean free path is shorter than 4mm, but in the present embodiment, is that the length of the gas discharge hole 113a of 50 μ m is set as 5mm with diameter, and is longer than mean free path.

Table 2

The mean free path of the electronics in the Ar gas atmosphere

Pressure (P) (Torr)	Mean free path (λ en) (mm)
		10	0.04
1	0.4
		0.1	4

λen(mm)＝0.4/P(Torr)

But,, therefore see that statistically existence scattering does not take place and the electronics of the longer distance of having advanced because mean free path is average distance after all.Therefore, in a technical scheme of the present invention, import the side setting at the gas of gas discharge hole 113a and have at the gas sintered body 114 of the porous ceramic of the coconnected pore of circulating direction.

For suppress plasma in pore adverse current, paradoxical discharge takes place in the second vertical hole 112b, the size of hole diameter is set as at below 2 times of lining thickness that are formed at the high-density plasma under the shower plate 105, preferably below lining thickness.The pore of the gas sintered body 114 of the porous ceramic in the present embodiment is that the narrow road of circulation path is below 10 μ m, with 10 ¹³Cm ^-3The lining thickness of high-density plasma promptly 10 μ m are identical or lower than it.By above-mentioned setting, for 10 ¹³Cm ^-3High-density plasma also can use this shower plate.

Employing has the shower plate 105 of said structure, can prevent that the gas of plasma in vertical hole 112 from importing side generation adverse current, thereby can suppress that shower plate 105 inner paradoxical discharges takes place, gas is piled up, so can prevent to be used to encourage the efficiency of transmission of the microwave of plasma, the decline of rate of finished products.In addition, can not can influence the efficient excitation in flatness ground plasma with contacted of plasma.Moreover, gas discharge hole 113a be utilize extrinsion pressing etc. be formed on the separate ceramic component 113 of shower plate 105 on, therefore compare with the situation of utilizing hole processing on shower plate, to form gas discharge hole, can be easy to form the fine and long gas discharge hole of diameter below 0.1mm.

In addition, supply with plasma excitation gas equably to processed substrate 103, and will handle gas row to processed substrate 103 by nozzle 120b from lower floor's shower plate 120, the result can be formed uniformly from being located at nozzle 120b on lower floor's shower plate 120 towards the air-flow of the processing gas of processed substrate 103, handles the composition that gas turns back to the top of shower plate 105 and tails off.The result has reduced because of being exposed to the decomposition of handling the processing gas molecule that excessively dissociating in the gas caused, even and to handle gas be that accumulation property gas also is difficult to take place produce the reduction etc. that microwave imports efficient because of the accumulation to shower plate 105, therefore cleaning time be can shorten, Treatment Stability and reproducibility improved, thereby boost productivity, and can carry out high-quality processing substrate.

In addition, number, diameter and the length of the first vertical hole 112a and the second vertical hole 112b, number, diameter and the length etc. that are opened in the gas discharge hole 113a on the ceramic component 113 are not limited to the numerical value of present embodiment.

Embodiment 2

Fig. 5 represents the second embodiment of the present invention.With reference to Fig. 5, the expression microwave plasma processing apparatus.Part with first embodiment repetition is marked identical Reference numeral, omit explanation.

In the present embodiment, on the top of process chamber 102 by the O RunddichtringO 106 of sealing usefulness on corresponding to the position that keeps the processed substrate 103 on the platform 104, as the part of the outer wall of process chamber 102 be equipped with as relative dielectric constant be 9.8 and low microwave dielectric loss (dielectric loss is 1 * 10 ^-4Below) dielectric that constitute by aluminium oxide, be formed with the i.e. tabular shower plate 201 in vertical hole 200 of many (230) peristomes.And, in process chamber 102 by the O RunddichtringO 203 of another sealing usefulness in the upper surface side of shower plate 201, promptly be positioned at respect to shower plate 201 with keeping on the platform 104 opposite sides cover plate 202 that is made of aluminium oxide being installed.

Fig. 6 is the schematic perspective view of the configuration of expression shower plate 201 and cover plate 202.With reference to Fig. 5 and Fig. 6, between the upper surface of shower plate 201 and cover plate 202, be formed with and be used for plasma excitation that filling is supplied to via being opened in the gas supply hole 204 that is communicated with in the shower plate 201 with supply port 110 from plasma excitation space 205 with gas.In other words, in cover plate 202, on position face, of shower plate 201 1 sides of cover plate 202, be provided with groove, thereby between shower plate 201 and cover plate 202, be formed with space 205 in the mode that is connected respectively corresponding to vertical hole 200 and gas supply hole 204.Promptly, vertical hole 200 disposes in the mode that is connected with space 205.

Fig. 7 is the vertical hole 200 of expression in detail.Among Fig. 7, (a) being cutaway view, (b) is upward view.Vertical hole 200 is made of the first vertical hole 200a of diameter 5mm, high 2mm and the second vertical hole 200b of diameter 10～20mm, high 8～20mm from process chamber 102 sides, and the part of the first vertical hole 200a and the second vertical hole 200b is equipped with the columned ceramic components 206 that are formed with gas discharge hole 206a that be made of aluminium oxide, 6 diameter 50 μ m, long 8mm.In addition, for concentrating, the electric field that prevents microwave discharges, plasma excitation makes plasma spontaneous with catching fire in the gas, to the bight enforcement chamfer machining 208 of the gas importing side in vertical hole 200.This chamfer machining is chamfered edge processing, more preferably rounding processing, also can carry out rounding processing to this bight after chamfered edge processing.

The shower plate 201 that employing has a said structure can prevent that plasma from importing the adverse current of side to the gas in vertical hole 200, but also the gas that can eliminate vertical hole 200 imports the phenomenon that the plasma excitation of side corner sections catches fire with gas.

Fig. 8 represents the preferred desired configuration of ceramic component 206.This figure (a) is a cutaway view, (b) is upward view.As shown in the drawing, the aperture that is preferably formed in the gas discharge hole 206a on the ceramic component 206 is about 2～5 μ m, and it is spaced apart about 10～20 μ m.

In order further to prevent the adverse current of plasma reliably, as shown in Figure 9, also can with the gas of the ceramic component 206 of the same size of Fig. 7 import side be located at ceramic component 206 on the gas discharge hole 206a mode setting that is connected have the porous ceramic sintered body 207 of the pore that is communicated with in the gas communication direction.At this, the gas of porous ceramic sintered body 207 imports second of side and indulges the space segment of hole 200b corresponding to technical solution of the present invention 5 described " gas passes through the hole ".

In addition, adopt purity at the Al more than 99.95% ₂O ₃Material, average crystallite particle diameter are that 1 μ m, bending strength are that 100MPa and average pore diameter are that the material that the 3 μ m and the porosity are 45%, thickness is 4mm is the porous ceramic sintered body 207 shown in Figure 9 of present embodiment.

In the present embodiment, also can obtain the effect same with first embodiment.

In addition, number, diameter and the length of the first vertical hole 200a and the second vertical hole 200b, number, diameter and the length etc. that are opened in the gas discharge hole 206a on the ceramic component 206 are not limited to the numerical value of present embodiment.

Embodiment 3

Figure 10 represents the third embodiment of the present invention.With reference to figure, the expression microwave plasma processing apparatus.Part with first and second embodiment repetition is marked identical Reference numeral, omit explanation.The vertical hole 300 of the shower plate 301 in the present embodiment is a structure shown in Figure 11.Promptly, offer the gas discharge hole 300a of diameter 0.05mm, long 0.5mm in process chamber 102 sides that are used to encourage plasma, the gas of gas discharge hole 300a imports side and is connected with the hole 300b of diameter 1mm.In addition, concentrate, the gas of hole 300b is imported the bight enforcement chamfer machining 303 of side for fear of the electric field of microwave.Then, be equipped with in the bottom of the hole of diameter 1mm 300b high 5mm columned, have a porous ceramic sintered body 302 at the coconnected pore of gas communication direction.In the present embodiment, because gas discharge hole 300a directly is opened on the shower plate that is made of aluminium oxide, therefore be difficult to the length of this gas discharge hole is located at more than the 1mm, thereby the mean free path than electronics is short, so electronics generation adverse current, plasma catches fire and catches fire phenomenon sometimes by lasting maintenance in space 205 and vertical hole 300 as a result.In order to prevent the above-described problem from occurring, import the porous ceramic sintered body 302 of the used material identical characteristic of side setting and second embodiment at the gas of gas discharge hole 300a.

In the present embodiment, also can obtain the effect same with first embodiment.

In addition, number, diameter and the length etc. of vertical hole 300, gas discharge hole 300a and hole 300b are not limited to the numerical value of present embodiment.

Embodiment 4

Figure 12 represents the fourth embodiment of the present invention.With reference to Figure 12, the expression microwave plasma processing apparatus.Part with first to the 3rd embodiment repetition is marked identical Reference numeral, omit explanation.

On the side of shower plate 400, laterally offer many cross-drilled holes 401 of diameter 1mm towards the center position ground of shower plate 400.Simultaneously, offer many (230) vertical hole 402 in the mode that is connected with this cross-drilled hole 401 communicatively towards process chamber 102.

Figure 13 represents to overlook the cross-drilled hole 401 of shower plate 400 and the configuration in vertical hole 402.Figure 14 is the schematic perspective view of the configuration in expression cross-drilled hole 401 and vertical hole 402.In addition, Figure 15 represents vertical hole 402 in detail.The length in vertical hole 402 is about 8～21mm, and diameter is at (preferably below 1mm) below the 3mm, and the leading section in vertical hole is equipped with cylindric about high 2～6mm and has porous ceramic sintered body 403 at the coconnected pore of gas communication direction.The porous ceramic sintered body uses following sintered body: be made of the alumina series material, the hole diameter of the narrow road in the gas flowing path that is formed by the pore that is communicated with is below 10 μ m, and dielectric loss is 1 * 10 ^-3Below, the average crystallite particle diameter is below 10 μ m, and the porosity is 20～75%, and average pore diameter is below 10 μ m, and maximum hole diameter is below 75 μ m, and bending strength is more than 30MPa.

Below explanation is equipped with the Production Example of the shower plate 400 of this porous ceramic sintered body 403.

Production Example 1

To being that 0.6 μ m and purity are 99.99% Al at average powder particle diameter ₂O ₃Cooperate the mist projection granulating powder of the mean particle diameter 70 μ m that obtain behind the paraffin of 3 quality % to carry out after the pressure forming in the powder, given size is processed in shapings such as external diameter, thickness, cross-drilled hole and vertical hole and forms the green compact body, this green compact body is carried out sintering and obtains relative density is 98% shower plate sintering blank.

On the other hand, about the porous ceramic sintered body, after obtaining presintering powder, add the above-mentioned shower plate Al that mixes 3 quality % with 800 ℃ of above-mentioned mist projection granulating powder of sintering at the state of powder ₂O ₃Powder carries out pressure forming and obtains the green compact body, and this green compact body is carried out sintering, thereby the hole diameter of the narrow road in the gas flowing path that obtains to be formed by the pore that is communicated with is that 2 μ m, dielectric loss are 2.5 * 10 ^-4, the average crystallite particle diameter is that 1.5 μ m, maximum crystalline particle diameter are that 3 μ m, the porosity are 40%, average pore diameter is that 3 μ m, maximum hole diameter are that 5 μ m, bending strength are the porous ceramic sintering body material of 300MPa.

After above-mentioned shower plate being finish-machined to 3.0 ± 0.001mm with the internal diameter in the vertical hole of sintering blank, the thickness of above-mentioned porous ceramic sintering body material is worked into 6mm and its outside dimension is finish-machined to 3.0～3.0-0.003mm, carry out ultrasonic waves for cleaning, as shown in figure 15, by porous ceramic sintered body 403 being pressed into vertical hole 402 chimeric the two.In addition, too small in chimeric surplus and under the situation that is difficult to be pressed into, be easy to be pressed into thereby in advance shower plate is heated to about 50～100 ℃.

Production Example 2

Prepared the green compact body of shower plate as follows, this shower plate with the green compact body be with the various pressure of 78～147MPa pair with after the identical mist projection granulating powder that obtains in above-mentioned Production Example 1 carries out pressure forming, shapings such as external diameter, thickness, cross-drilled hole and vertical hole are processed into given size forms.

On the other hand, as porous ceramic sintering body material, powder compact, degreasing body and presintering body have been prepared, this powder compact is to obtain after the green compact body identical with above-mentioned Production Example 1 is processed into the regulation shape obtaining, this degreasing body forms with 450 ℃ of these powder compacts of sintering, and this presintering body further forms with 600 ℃ of sintering.

In addition, above-mentioned shower plate is different because of the difference of pressure forming pressure with the sintering shrinkage of green compact body, is 19% at sintering shrinkage under the situation of 78MPa, shrinkage is 16.2% under the situation at 147MPa.In addition, the sintering shrinkage of porous ceramic sintering body material all can change when each change porosity, hole diameter, different sintering shrinkages because of pressure forming pressure also can change in addition, therefore all will investigate sintering shrinkage in advance when the characteristic of each setting porous ceramic sintered body.

To have with above-mentioned shower plate and be installed in vertical Kong Zhonghou with powder compact, degreasing body or the presintering body of the porous ceramic sintered body of the identical and even a little littler sintering shrinkage of the sintering shrinkage of green compact body, simultaneously sintering they.Thereby, because they produce sintering cohesive force each other, therefore can guarantee to install securely, fix.

Production Example 3

Thereby obtain the degreasing body with the green compact body with 450 ℃ of sintering and above-mentioned Production Example 1 and Production Example 2 identical shower plates.In addition, the sintering shrinkage of this degreasing body is identical with the sintering shrinkage of green compact body.

In addition, with 600～1000 ℃ of sintering (presintering) thus shower plate obtains the presintering body with the green compact bodies.Under the situation that obtains the presintering body, shrink owing to some sintering take place in the presintering stage, therefore pre-sintering temperature is high more when formal sintering presintering body, and the sintering shrinkage of remaining presintering body is low more.

On the other hand, what utilize porous ceramic sintering body material use that the method for making identical with above-mentioned Production Example 1 and Production Example 2 obtain is that the mist projection granulating powder is carried out the powder that obtains after the presintering, therefore sintering shrinkage is littler with the sintering shrinkage of green compact body than shower plate, close with shower plate with the sintering shrinkage of the presintering body of green compact body, thus be convenient to selected sintering shrinkage identical shower plate material and porous ceramic sintering body material.

In this Production Example, also with above-mentioned Production Example 2 similarly simultaneously the sintering shower plate with material be installed in porous ceramic sintering body material in the vertical hole of this shower plate, thereby can guarantee to install securely, fix because of generation sintering cohesive force each other.

In addition, also the shower plate of preparing according to Production Example 2 is in advance calculated the size behind the sintering of indulging the hole with the sintering shrinkage of green compact body, the size of size behind the sintering of the green compact body of porous ceramic material, degreasing body, presintering body and the sintered body porous ceramic material of calculating size big (about 1～50 μ m) after than the sintering in above-mentioned vertical hole is installed in the vertical hole of above-mentioned green compact body and the while sintering they, thereby reach the firm structure that installs and fixes with mutual generation sintering cohesive force and continuous crystalline structure.

In addition, be installed in ceramic component (113,206,404) in the vertical hole of shower plate also can utilize with above-mentioned Production Example 1～3 in the identical method of method of explanation, carrying out being installed on the position of regulation behind the sintering simultaneously with shower plate.

As mentioned above, because Debye length reduces when the density of plasma rises, therefore we can say that from this viewpoint of adverse current that prevents plasma the aperture of preferred porous ceramic sintered body 403 is littler.Particularly, the size of average pore diameter is at below 2 times of lining thickness of plasma, preferably below lining thickness.In addition, the pore of porous ceramic sintered body 403 is that the narrow road of gas flowing path is below 10 μ m, with 10 ¹³Cm ^-3The lining thickness of high-density plasma promptly 10 μ m are identical or littler than it.By above-mentioned setting, for 10 ¹³Cm ^-3High-density plasma also can use this shower plate.

The shower plate 400 that has said structure by use, can prevent that the gas of plasma in the vertical hole 402 of this shower plate from importing side generation adverse current, thereby can suppress that shower plate 400 inner paradoxical discharges takes place, gas is piled up, so can prevent to be used to encourage the through-put power of the microwave of plasma, the decline of rate of finished products.

At this, in order to make the plasma excitation of discharging not have local irregular ground, discharge with even flow, flow as far as possible at least from whole face with gas from the porous gas flow body that is installed in the single vertical hole, under the situation of using hole diameter and the porous gas flow body of ventilation rate in more among a small circle, in order to ensure the flow of the plasma excitation of being discharged with gas, the thickness with the porous gas flow body is decreased to about 2～3mm sometimes.Under the situation of the bigger porous gas flow body of the hole diameter of the situation of using this kind than thin porous gas flow body, use average pore diameter and narrow road, in order to prevent the adverse current of plasma more reliably, shown in Figure 16 (a), also can make the ceramic component 404 that offers a plurality of gas stream through hole 404a import side and be connected with the gas of porous ceramic sintered body 403.Ceramic component 404 is that (dielectric loss is 1 * 10 for high-purity alpha-alumina more than 99.95% ^-3Below) the extrusion modling product, the diameter in the aperture of gas stream through hole 404a is 50 μ m.This numerical value is less than as 10 ¹²Cm ^-32 times of 40 μ m of lining thickness of high-density plasma, greater than as 10 ¹³Cm ^-32 times of 10 μ m of lining thickness of high-density plasma.In addition, the length of gas stream through hole 404a is 5mm.

The length of preferred this gas stream through hole 404a is that mean free path is long than the average distance before the electronics generation scattering.As mentioned above, mean free path and pressure are inversely proportional to, and are 4mm when 0.1Torr.In fact, because that the gas of gas stream through hole 404a imports the pressure of side is higher, so mean free path is shorter than 4mm, but in the present embodiment, and the length of gas stream through hole 404a is set as 5mm, and is longer than mean free path.

Shown in Figure 16 (b), import side at the gas of porous ceramic sintered body 403 and another porous ceramic sintered body 403a is set replaces above-mentioned ceramic component 404, thereby can prevent the adverse current of plasma more reliably.In this case, in order to reduce the crushing of plasma excitation with gas, use the porosity and hole diameter to discharge the big sintered body of the porosity of porous ceramic sintered body 403 of side and hole diameter imports side as gas porous ceramic sintered body 403a (average pore diameter for example: 10～30 μ m, the porosity: 50～75%) than gas.

Figure 17 represents another installation example of porous ceramic sintered body 403.

In the example of Figure 17 (a), the large diameter second vertical hole 402b is set, this second vertical hole 402b is installed among the second vertical hole 402b as the installation portion of porous ceramic sintered body 403 and with porous ceramic sintered body 403 at first front end of indulging hole 402a.In addition, in the example of Figure 17 (a), import explanation ceramic component 404 identical, that offer a plurality of gas stream through hole 404a among (a) of side setting and Figure 16 at the gas of porous ceramic sintered body 403.Thereby can prevent the adverse current of plasma more reliably.In addition, also can similarly import side at the gas of porous ceramic sintered body 403 with Figure 16 (b) is provided with another porous ceramic sintered body and replaces ceramic component 404.

The shape that the example of Figure 17 (b) will be installed in the porous ceramic sintered body 403 among the second vertical hole 402b is set as its upper surface and lower surface all bend to the concave curved surface shape towards process chamber 102 shape.In addition, the example of Figure 17 (c) shape that will be installed in the porous ceramic sintered body 403 among the large diameter second vertical hole 402b that is located at the first vertical hole 402a front end is set as its upper surface and lower surface all bend to convex surface shape towards process chamber 102 shape.At this, porous ceramic sintered body 403 is not installed from the outstanding mode of the lower surface of shower plate 400 with its lower end.The porous ceramic sintered body 403 of curved shape like that among (b) by using Figure 17 and (c) of Figure 17, the stress that produces because of thermal expansion, contraction in the time of can utilizing distortion (deflection) to be absorbed in to use shower plate 400, thereby the crackle etc. that can prevent porous gas flow body 403 and the shower plate 400 of this porous gas flow body 403 is installed.In addition, shown in Figure 17 (c), form towards process chamber 2 under the situation of convex surface shape,, therefore can produce more uniform plasma owing to can scope discharge plasma excitation gas widelyer at porous ceramic sintered body 403.In addition, in the example of Figure 17 (b) and Figure 17 (c), also can import the side setting at the gas of porous ceramic sintered body 403 and offer the ceramic component of a plurality of gas stream through holes or other porous ceramic sintered body.

In the above-described embodiments, number, diameter and the length etc. of vertical hole 112a are not limited to the numerical value of present embodiment.

Embodiment 5

Figure 18 represents the fifth embodiment of the present invention.With reference to Figure 18, the expression microwave plasma processing apparatus.Part with first to fourth embodiment repetition is marked identical Reference numeral, omit explanation.

In the present embodiment, on the top of process chamber 102 by the O RunddichtringO 106 of sealing usefulness on corresponding to the position that keeps the processed substrate 103 on the platform 104, as the part of the outer wall of process chamber 102 be equipped with as relative dielectric constant be 9.8 and low microwave dielectric loss (dielectric loss is 1 * 10 ^-4Below) dielectric that constitute by aluminium oxide, be formed with the i.e. tabular shower plate 501 in vertical hole 500 of many (230) peristomes.And, in process chamber 102 by the O RunddichtringO 203 of another sealing usefulness in the upper surface side of shower plate 501, promptly be positioned at respect to shower plate 501 with keeping on the platform 104 opposite sides cover plate 202 that is made of aluminium oxide being installed.

Figure 19 is the schematic perspective view of the configuration of expression shower plate 501 and cover plate 202.With reference to Figure 18 and Figure 19, be formed with space 205 between the upper surface of shower plate 501 and cover plate 202, this space 205 is filled with the plasma excitation gas that is supplied to via the gas supply hole 204 that is opened in the connection in the shower plate 501 with supply port 110 from plasma excitation.In other words, in cover plate 202, on position face, of shower plate 501 1 sides of cover plate 202, be provided with groove, thereby between shower plate 501 and cover plate 202, be formed with space 205 in the mode that is connected respectively corresponding to vertical hole 500 and gas supply hole 204.Promptly, vertical hole 500 disposes in the mode that is connected with space 205.

Figure 20 is the vertical hole 500 of expression in detail.Vertical hole 500 is made of the first vertical hole 500a of diameter 8mm, high 3mm and the second vertical hole 500b of diameter 10mm, high 7mm from process chamber 102 sides, utilize be entrenched in the first vertical hole 500a and the second vertical hole 500b the porous ceramic sintered body 502 that has at the coconnected pore of gas communication direction is installed on the whole.The periphery except upper surface and lower surface of porous ceramic sintered body 502 is formed by compact substance ceramic layer 502a, the inner porous matter 502b of portion that forms.The structure of the porous matter 502b of portion is identical with the porous ceramic sintered body 403 of the 4th embodiment.Compact substance ceramic layer 502a has the characteristic value identical with shower plate 501, particularly, by dielectric loss 1 * 10 ^-3Below, Al ₂O ₃Purity more than 99.95% and relative density form at the material more than 98%.

Can utilize for example following method to make the above-mentioned porous ceramic sintered body 502 that has compact substance ceramic layer 502a in periphery.

Promptly, will be adjusted to powder filling that the porous gas flow body uses in cylindric rubber pattern and after carrying out cold fluid static pressure pressure (CIP) moulding, the columned formed body of having processed periphery is installed in the center of the cylindric rubber pattern bigger than above-mentioned rubber pattern size, adjustment powder in its outside filling compact substance pottery usefulness, CIP moulding and obtain formed body once more, with this formed body of set point of temperature sintering, thereby can obtain the porous gas flow body of double-layer structural.In addition, importantly so that the sintering of the porous material portion of central part shrinks and the sintering contraction phase mode together of the compact substance material portion of periphery is set each CIP condition of molding.

In the present embodiment, also can obtain the effect identical with the 4th embodiment.

In addition, number, diameter and the length etc. of the first vertical hole 500a and the second vertical hole 500b are not limited to the numerical value of present embodiment.

Industrial utilizability

Shower plate of the present invention also can utilize in the various plasma processing apparatus such as parallel plate-type high frequency pumping plasma processing apparatus, device for processing inductive coupling plasmas except utilizing in microwave plasma processing apparatus.

Claims (26)

1. shower plate, this shower plate is disposed at plasma processing apparatus, discharges plasma excitation gas in order to produce plasma in above-mentioned plasma processing apparatus,

In forming the vertical hole of plasma excitation with the discharge path of gas the porous gas flow body that has at the coconnected pore of gas communication direction is installed, the hole diameter of the narrow road in the gas flowing path that is formed by the pore of the connection of above-mentioned porous gas flow body is below the 10 μ m.

2. shower plate according to claim 1,

Above-mentioned porous gas flow body is made of the alumina series material, dielectric loss below 1 * 10-3, the average crystallite particle diameter below the 10 μ m, in the scope of the porosity 20～75%, average pore diameter below the 10 μ m, maximum hole diameter below 75 μ m, bending strength is more than 30MPa.

3. shower plate according to claim 1 and 2,

Discharge side at the gas in above-mentioned vertical hole and be provided with gas discharge hole, the gas that above-mentioned porous gas flow body is configured in the above-mentioned gas tap imports side.

4. shower plate according to claim 3,

The aperture of above-mentioned gas tap is below 2 times of lining thickness that are formed at the plasma under the shower plate.

5. according to claim 3 or 4 described shower plates,

Importing side at the gas of above-mentioned porous gas flow body is provided with continuously than the big gas in above-mentioned gas tap aperture and passes through the hole.

6. according to each described shower plate in the claim 3～5,

The ceramic component that offers a plurality of gas discharge holes is installed in the vertical hole that is opened on the shower plate.

7. shower plate, this shower plate is disposed at plasma processing apparatus, has to discharge a plurality of gas discharge holes of plasma excitation in order in above-mentioned plasma processing apparatus, to produce plasma with gas,

The length length of gas discharge hole is longer than the mean free path of the electronics in the above-mentioned plasma processing apparatus.

8. according to each described shower plate in the claim 1～7,

Gas discharge hole is located at the gas that is opened in the vertical hole on the shower plate and discharges side, the gas in above-mentioned vertical hole is discharged the bight of side and implements chamfer machining.

9. a shower plate is used for plasma processing apparatus,

This shower plate has a plurality of vertical holes, and the gas in each vertical hole is discharged the member obstruction that side is provided with a plurality of gas discharge holes, and the length of each gas discharge hole is longer than the mean free path of the electronics in the above-mentioned plasma processing apparatus.

10. shower plate according to claim 9,

It is narrower than gas importing side that the above-mentioned gas in above-mentioned vertical hole is discharged side, and above-mentioned member is located in this narrow and imports side along gas and extends.

11. according to claim 9 or 10 described shower plates,

Above-mentioned member is the extrusion modling product of pottery.

12. according to each described shower plate in the claim 9～11,

Gas in above-mentioned vertical hole imports side and disposes the porous gas flow body that has at the coconnected pore of gas communication direction in the mode that is connected with above-mentioned a plurality of gas discharge holes.

13. according to each described shower plate in the claim 9～11,

The aperture of above-mentioned gas tap is below 2 times of lining thickness that are formed at the plasma under the shower plate.

14. shower plate according to claim 12,

The aperture of the pore of above-mentioned porous gas flow body is to be formed at below the lining thickness of the plasma under the shower plate.

15. shower plate according to claim 1 and 2 utilizes chimeric or sinter bonded is installed in above-mentioned porous gas flow body on the leading section at least in above-mentioned vertical hole.

16. shower plate according to claim 15,

The upper surface of porous gas flow body and lower surface all bend to convex surface shape or concave curved surface shape in above-mentioned plasma processing apparatus.

17. shower plate according to claim 15,

The periphery except upper surface and lower surface of porous gas flow body is formed by the compact substance ceramic layer.

18. according to each described shower plate in the claim 15～17,

In the gas of porous gas flow body imports the vertical hole of side, ceramic component or the porosity another porous gas flow body bigger than the porosity of above-mentioned porous gas flow body of having offered the gas stream through hole is installed.

19. the manufacture method of a shower plate, this method are used to make the described shower plate of claim 1,

Utilize chimeric installation have internal diameter size with respect to the vertical hole of shower plate be 0～-the porous gas flow body of the outside dimension of 0.002mm.

20. the manufacture method of a shower plate, this method are used to make the described shower plate of claim 1,

To carry out moulding to the material powder of porous gas flow body and be processed into that the degreasing body of the powder compact that obtains after the regulation shape, powder compact or presintering body are installed in that material powder to shower plate carries out moulding and after being processed to form in the vertical hole of green compact body in vertical hole, with the degreasing body of above-mentioned powder compact, powder compact or presintering body and this green compact body sintering simultaneously.

21. the manufacture method of a shower plate, this method are used to make the described shower plate of claim 1,

To carry out moulding to the material powder of porous gas flow body and be processed into that the degreasing body of the powder compact that obtains after the regulation shape, powder compact or presintering body are installed in that material powder to shower plate carries out moulding and after being processed to form in the vertical hole of degreasing body of green compact body in vertical hole, with the degreasing body of the degreasing body of above-mentioned powder compact, powder compact or presintering body and this green compact body sintering simultaneously.

22. the manufacture method of a shower plate, this method are used to make the described shower plate of claim 1,

To carry out moulding to the material powder of porous gas flow body and be processed into that the degreasing body of the powder compact that obtains after the regulation shape, powder compact or presintering body are installed in that material powder to shower plate carries out moulding and after being processed to form in the vertical hole of presintering body of green compact body in vertical hole, with the presintering body of the degreasing body of above-mentioned powder compact, powder compact or presintering body and this green compact body sintering simultaneously.

23. the manufacture method of a shower plate,

Green compact body, degreasing body, presintering body or the sintered body that will have a ceramic component of a plurality of gas discharge holes or gas stream through hole is enclosed in material powder carried out moulding and after being processed to form in the above-mentioned vertical hole of green compact body, degreasing body or presintering body of the shower plate in vertical hole, simultaneously sintering they.

24. a plasma processing apparatus,

This plasma processing unit disposes each described shower plate in the claim 1～18.

25. a method of plasma processing,

Each described shower plate is supplied with plasma excitation gas in the use claim 1～18 in plasma processing apparatus, thereby the plasma excitation that utilizes microwave excitation to supply with produces plasma with gas, uses this plasma that substrate is implemented oxidation, nitrogenize, oxynitriding, CVD, etching or plasma irradiating.

26. the manufacture method of an electronic installation,

Comprise the operation of utilizing the described method of plasma processing of claim 25 to come treatment substrate.

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