CN108649079A

CN108649079A - Finger-like with passivation contact structures intersects back contacts solar cell and preparation method thereof

Info

Publication number: CN108649079A
Application number: CN201810760071.XA
Authority: CN
Inventors: 李华; 李中兰; 鲁伟明; 靳玉鹏
Original assignee: Taizhou Longi Solar Technology Co Ltd
Current assignee: Taizhou Longi Solar Technology Co Ltd
Priority date: 2018-07-11
Filing date: 2018-07-11
Publication date: 2018-10-12

Abstract

The present invention relates to a kind of finger-like with passivation contact structures to intersect back contacts solar cell battery structure and preparation method thereof, includes successively from top to bottom along 1 thickness direction of silicon base：Include successively from top to bottom along silicon base thickness direction：Front passivation and antireflective coating, front doped layer, n-type silicon substrate, passivating back tunnel layer, back side doped layer, backside passivation film and battery electrode；The back side doped layer is made of the first doped region and the second doped region, the first doped region and the second doped region structure it is identical and be in finger-like cross arrangement；The battery electrode includes positive electrode and negative electrode, and positive electrode is contacted with the second doped region, the contact of the first doped region of negative electrode；The structure can preferably avoid the possibility for spatially causing leakage current.Battery is improved in the reliable sex expression of later product, reduces the technology difficulty of battery component.

Description

Finger-like with passivation contact structures intersects back contacts solar cell and preparation method thereof

Technical field

The invention belongs to technical field of solar batteries, more particularly to a kind of finger-like with passivation contact structures intersects the back of the body Contact the battery structure and preparation method thereof of solar cell.

Background technology

Currently, gradually exhausting with fossil energy, for solar cell as new energy substitution scheme, use is more and more wider It is general.Solar cell is the device that the luminous energy of the sun is converted to electric energy.Solar cell generates carrier using photogenic voltage principle, Then carrier is drawn using electrode, to be conducive to efficiently use electric energy.

Finger-like intersects back contact battery, also known as IBC batteries.Wherein IBC refers to Interdigitated back Contact finger-like intersects back contacts.The feature of IBC battery maximums is the back side of emitter and metal contact all in battery, just Face does not have the influence that metal electrode blocks, therefore has higher short circuit current Jsc, while the back side can allow wider metal Grid line reduces series resistance Rs to improve fill factor FF；And the unobstructed battery in this front not only transfer efficiency Height, and seem more attractive, meanwhile, the component of all back-contact electrodes is easier to assemble.IBC batteries are current realization high-efficiency crystal silicons One of technique direction of battery.

Finger-like used at present intersect the backside structure of back contacts solar cell usually using through p-type doped region and Then N-shaped doped region uses the electrode of penetration type or non-through formula and insulating materials is combined to carry out positive and negative anodes insulation, therefore making When standby IBC batteries, it is sometimes desirable to the additional preparation process for carrying out insulator, and it is positive and negative due to being had on silicon wafer thickness direction The phenomenon that electrode coexists, or there is on silicon wafer thickness direction n-type region and anode coexist, p-type area and cathode coexist asks Topic, has large effect to the reliability of the battery in later stage, also larger welding can be caused tired in the preparation of continuous battery component It is difficult.

Invention content

In view of the above problems, the present invention provides a kind of finger-like with passivation contact structures to intersect back contacts solar cell Battery structure and preparation method thereof can preferably solve the above problems.Battery is improved in the reliable sex expression of later product, is subtracted The technology difficulty of few battery component.

To achieve the above object, technical solution of the invention is,

A kind of finger-like intersection back contacts solar cell with passivation contact structures, from top to bottom along silicon base thickness direction Include successively：Front passivation and antireflective coating, front doped layer, n-type silicon substrate, passivating back tunnel layer, back side doped layer, the back of the body Face passivating film and battery electrode；The back side doped layer is made of the first doped region and the second doped region, the first doped region Domain and the second doped region finger-like cross arrangement；The battery electrode includes positive electrode and negative electrode；

First doped region includes the first pass-through zone and the first vertical area, and second doped region includes the Two pass-through zones and the second vertical area；First pass-through zone and the second pass-through zone are mutually parallel；First vertical area It is mutually perpendicular to and connects with the first pass-through zone；Second vertical area and the second pass-through zone are mutually perpendicular to and connect； On first pass-through zone direction, the first vertical area and the second vertical area are staggered；

The positive electrode includes just superfine grid line and positive connection electrode, and the negative electrode includes the thin grid line of cathode and cathode Connection electrode；The thin grid line of cathode is contacted with the formation of the first vertical area of the first doped region；Just superfine grid line and the second doping Second vertical area in region forms contact；Cathode connection electrode is arranged in the first pass-through zone；Positive connection electrode setting In the second pass-through zone；Just superfine grid line is connected with positive connection electrode, and passes through positive connection electrode derived current, negative electricity Pole includes that the thin grid line of cathode is connected with cathode connection electrode, and passes through cathode connection electrode derived current.

At least partly there are area of isolation, width between the second doped region of the first doped region of the back side and the back side For 2~200um.

One first of the width of one the second vertical area of second doped region and adjacent first doped region The sum of width of vertical area is 0.2~5mm, wherein the width ratio of the width of the second vertical area and the first vertical area is 1~20.

First pass-through zone width of first doped region is 0.08~5mm；The second of second doped region The width of pass-through zone is 0.08~5mm.

The just superfine grid line is made of one or more in silver, aluminium, copper or nickel, and the width of just superfine grid line is 20um ~200um；The thin grid line of cathode is made of silver, one or more in copper and mickel, the width of the thin grid line of cathode be 20um~ 200um。

The anode connection electrode and cathode connection electrode are made of one or more in silver, copper, aluminium or nickel；It is described Positive connection electrode is 1-40 roots, and the cathode connection electrode is 1-40 roots.

The front passivation and antireflective coating, using silicon nitride, silica, silicon oxynitride, aluminium oxide, silicon carbide, amorphous One or more compositions in silicon；The passivating film at the back side, using silicon nitride, silica, silicon oxynitride, aluminium oxide, carbonization One or more compositions in silicon, non-crystalline silicon.

The passivating back tunnel layer is intrinsic amorphous silicon, silicon nitride, silica, silicon oxynitride, aluminium oxide, carbonization One kind in silicon.

The front surface doped layer be n-type silicon substrate homogeneity doped layer, the n-type silicon substrate homogeneity doped layer doped with V group element, doping concentration are 1 × 10¹⁷~5 × 10²¹cm^-3。

The front surface doped layer be p-type silicon substrate homogeneity doped layer, the p-type silicon substrate homogeneity doped layer doped with Group-III element, doping concentration are 1 × 10¹⁷~5 × 10²¹cm^-3。

The front surface doped layer is the heterogeneous doping film layer of N-shaped, and the heterogeneous doping film layer of N-shaped is close to n-type silicon substrate Side includes that one layer of front is passivated tunnel layer；It is described front passivation tunnel layer be non-crystalline silicon, silicon nitride, silica, silicon oxynitride, One kind in aluminium oxide, silicon carbide；The heterogeneous doping film layer of p-type is by one or more in polysilicon, non-crystalline silicon, microcrystal silicon Composition, and doped with V group element, doping concentration is 1 × 10¹⁷~5 × 10²¹cm^-3。

The front surface doped layer is the heterogeneous doping film layer of p-type；The heterogeneous doping film layer of p-type is close to n-type silicon substrate Side includes that one layer of front is passivated tunnel layer；It is described front passivation tunnel layer be non-crystalline silicon, silicon nitride, silica, silicon oxynitride, One kind in aluminium oxide, silicon carbide；The heterogeneous doping film layer of p-type is by one or more in polysilicon, non-crystalline silicon, microcrystal silicon Composition, and doped with group-III element, doping concentration is 1 × 10¹⁷~5 × 10²¹cm^-3。

A kind of preparation method that there is the finger-like of passivation contact structures to intersect back contacts solar cell, includes the following steps：

1) surface-texturing is carried out to n-type silicon substrate front surface；

2) passivating back tunnel layer is formed in n-type silicon backside of substrate；Second is graphically formed in n-type silicon backside of substrate again to mix Miscellaneous region and the first doped region so that the first doped region and the second doped region are staggered in finger-like cross modal； Silicon base front prepares n-type surface doped layer or p-type front surface doped layer；

3) backside passivation film is prepared in n-type silicon backside of substrate again, front passivation and antireflective is prepared in n-type silicon substrate front surface Film；

4) overleaf battery electrode is prepared on passivating film.

Further include in step 2)：N-type silicon backside of substrate formed passivating back tunnel layer while, n-type silicon substrate just Face forms front passivation tunnel layer.

Further include step before step 3)：Overleaf formed on the second doped region and the back side the first doped region boundary every From region.

In step 4), positive electrode is contacted with the second doped region, and negative electrode is contacted with the first doped region, electrode and doping The contact in region is burnt backside passivation film formation using electrode slurry and is in direct contact, or opens diaphragm area and pre- in advance by setting Diaphragm area formation is opened to be in direct contact.

The beneficial effects of the invention are as follows：

There is the present invention finger-like of passivation contact structures to intersect back contacts solar cell, the first doped region and the second doping Regional structure is identical to be all made of " rich " word structure and is in finger-like cross arrangement, using being alternatively arranged and the second doped region is vertical Portion and the first doped region vertical component effect are mutually clamped so that positive electrode and negative electrode do not have overlay region on cell thickness direction Domain avoids the possibility for spatially causing leakage current..N-type region includes the first pass-through zone and the first vertical area, states p Type region includes the second pass-through zone and the second vertical area；First vertical area intersects vertically to form office with the first pass-through zone Portion is the structure in rich font, and the second pass-through zone and the second vertical area intersect vertically to form part as in the knot of rich font Structure, and then misplace and formed in finger-like cross modal staggered structure.Positive electrode is contacted with the second doped region, negative electrode setting It is contacted in the first doped region, and its width is respectively less than corresponding doped region so that there is no n-type area on silicon wafer thickness direction The problem of domain and anode coexist, p-type area and cathode coexist, avoids the possibility for spatially causing leakage current.

Further, and the area of isolation between the first doped region and the second doped region so that the first doped region It is separated from each other in boundary with the second doped region, eliminates the insulator design between positive electrode and negative electrode, it is possible to reduce Technological process reduces space complexity.So that battery has larger reliability, contribute in the preparation of continuous battery component to subtract Few welding difficulty.

Further, there is one layer of front passivation tunnel layer between front surface doped layer and silicon base, adulterated using N-shaped as just Surface doped region, in this case, positive p-type doped layer and front passivation tunnel layer form the heterogeneous pn to float in front surface Knot, can be greatly enhanced the passivation of front surface.

While improving reliable sex expression of the battery in later product, process is simple, at low cost for the preparation side of the present invention, Reduce the technology difficulty of battery component.

Description of the drawings

Fig. 1 is the structural upright schematic diagram of a specific embodiment in embodiment.

Fig. 2 is the structural upright schematic diagram of a specific embodiment in embodiment.

Fig. 3 is the structural upright schematic diagram of a specific embodiment in embodiment.

Fig. 4 is the structural upright schematic diagram of a specific embodiment in embodiment.

Fig. 5 is the structural upright schematic diagram of a specific embodiment in embodiment.

Fig. 6 is the structural upright schematic diagram of a specific embodiment in embodiment.

Fig. 7 is the structural plan schematic diagram of a specific embodiment in embodiment.

Fig. 8 is the structural plan schematic diagram of a specific embodiment in embodiment.

Fig. 9 is the structural plan schematic diagram of a specific embodiment in embodiment.

Figure 10 is the electrode schematic diagram of a specific embodiment in embodiment.

Figure 11 is the electrode schematic diagram of a specific embodiment in embodiment.

Wherein, 1 is silicon base, and 2 penetrate film for front passivated reflection reducing, and 3 be the first doped region, and 4 be the second doped region, 5 It is the superfine grid of negative electricity for backside passivation layer, 6,7 be positive-electrode fine grid, and 8 be cathode connection electrode, and 9 be positive connection electrode, and 10 are Area of isolation, 11 be passivating back tunnel layer, and 12 be front doped layer, and 13 be front passivation tunnel layer；301 run through area for first Domain, 302 be the first vertical area, and 401 run through area for second, and 402 be the second vertical area.

Specific implementation mode

The technology of the present invention is described in detail below in conjunction with the accompanying drawings：

As shown in Fig. 1 to 11, a kind of finger-like intersects back contacts solar cell, on 1 thickness direction of silicon base from top to bottom according to It is secondary to include：Front passivation and antireflective coating, n/p type front surfaces doped layer 12, n-type silicon substrate 1, passivating back tunnel layer 11, the back of the body Adulterate film layer 3 and 4, backside passivation film and battery electrode in face；

Back side doping film layer is made of the first doped region of the back side 3 and the second doped region of the back side 4；First doped region 3 Doped with V group element, the second doped region 4 is doped with group-III element；The second doped region of the first doped region of the back side 3 and the back side Domain 4 is staggered in finger-like cross modal, and wherein the first doped region of the back side 3 includes that the first pass-through zone 301 and first is vertical Region 302, the second doped region of the back side 4 include the second pass-through zone 401 and the second vertical area 402；First pass-through zone 301 It is mutually parallel with the second pass-through zone 401；First vertical area 302 and the first pass-through zone 301 are mutually perpendicular to and connect；Second Vertical area 402 and the second pass-through zone 401 are mutually perpendicular to and connect；On 301 direction of the first pass-through zone, the first vertical area Domain 302 and the second vertical area 402 are staggered；

First doped region, 3 second doped region, 4 first doped region, 3 second doped region, 4 first doped region 3 second The battery electrode of doped region 4 includes positive electrode and negative electrode, and positive electrode includes just superfine grid line 7 and positive connection electrode 9, is born Electrode includes the thin grid line 6 of cathode and cathode connection electrode 8；

The thin grid line of cathode is contacted with the formation of the first vertical area 302 of the first doped region of the back side 3；Just superfine grid line and the back of the body Second vertical area 402 of the second doped region of face 4 forms contact；Cathode connection electrode 8 is arranged in the first pass-through zone 301 It is interior；Positive connection electrode 9 is arranged in the second pass-through zone 401；Just superfine grid line is connect with positive connection electrode 9, and is passed through 9 derived current of positive connection electrode, the thin grid line of cathode is connect with cathode connection electrode 8, and is exported by negative electrode connection electrode Electric current.

It preferably, can also at least partly there are isolation between the first doped region of the back side 3 and the second doped region of the back side 4 Region 10 separates the first doped region 3 and the second doped region 4,10 width of area of isolation be 2~200um.The back side second The width of one the second vertical area 402 of doped region 4 and first vertical area of the first doped region of the adjacent back side 3 The sum of 302 width is 0.2~5mm, wherein the width ratio of the width of the second vertical area 402 and the first vertical area 302 Between 1~20.301 width of the first pass-through zone of the first doped region of the back side 3 is 0.08~5mm；The second doped region of the back side The width of second pass-through zone 401 in domain 4 is 0.08~5mm.

Preferably, the first doped region of the back side 3 is made of one or more in polysilicon, non-crystalline silicon, microcrystal silicon, and is mixed It is miscellaneous to have V group element；The second doped region of the back side 4 is made of one or more in polysilicon, non-crystalline silicon, microcrystal silicon, and is adulterated There is group-III element.Passivating back tunnel layer 11 is intrinsic amorphous silicon, silicon nitride, silica, silicon oxynitride, aluminium oxide, carbonization One kind in silicon.Positive passivation and antireflective coating, using in silicon nitride, silica, silicon oxynitride, aluminium oxide, silicon carbide, it is non- One or more compositions of crystal silicon；The passivating film at the back side, using silicon nitride, silica, silicon oxynitride, aluminium oxide, silicon carbide, non- One or more compositions in crystal silicon.

7 line main conductive of positive-electrode fine grid at including one or more in silver, aluminium, copper or nickel, 7 line of positive-electrode fine grid Width is 20um~200um.Superfine 6 line of grid of negative electricity is made of one or more in silver, copper or nickel, superfine 6 line of grid of negative electricity Width is 20um~200um.Positive electrode connection electrode and negative electrode connection electrode are by one kind of silver, aluminium, copper or nickel or a variety of groups At.Positive electrode connection electrode is 1-40 roots, and negative electrode connection electrode is 1-40 roots.N-shaped front surface doped layer 12 is n-type silicon substrate 1 homogeneity doped layer.N-shaped front surface doped layer 12 can be replaced p-type front surface doped layer 12, and p-type front surface doped layer 12 is p-type 1 homogeneity doped layer of silicon base.

Wherein, N-shaped front surface doped layer 12 or the heterogeneous doped layer of N-shaped, the heterogeneous doped layer of N-shaped is close to n-type silicon base 1 side of bottom includes that one layer of front is passivated tunnel layer 13；Front passivation tunnel layer 13 is non-crystalline silicon, silicon nitride, silica, nitrogen oxidation One kind in silicon, aluminium oxide, silicon carbide；The heterogeneous doped layer of p-type is by one or more groups in polysilicon, non-crystalline silicon, microcrystal silicon At, and doped with V group element.

N-shaped front surface doped layer 12 can be replaced the heterogeneous doped layer of p-type；The heterogeneous doped layer of p-type is close to n-type silicon substrate 1 Side includes that one layer of front is passivated tunnel layer 13；Front passivation tunnel layer 13 be non-crystalline silicon, silicon nitride, silica, silicon oxynitride, One kind in aluminium oxide, silicon carbide；The heterogeneous doped layer of p-type is made of one or more in polysilicon, non-crystalline silicon, microcrystal silicon, And doped with group-III element.

1) surface-texturing is carried out to 1 front of n-type silicon substrate；

2) passivating back tunnel layer 11 is formed at 1 back side of n-type silicon substrate；The is formed n-type silicon substrate 1 is back-patterned again Two doped regions 4 and the first doped region 3 so that the first doped region 3 and the second doped region 4 interlock in finger-like cross modal Arrangement；N-type surface doped layer or p-type front surface doped layer are prepared in 1 front of silicon base；

3) backside passivation film 5 is prepared at 1 back side of n-type silicon substrate again, front passivation is prepared in 1 front of n-type silicon substrate and subtracted Reflectance coating 2；

4) overleaf battery electrode is prepared on passivating film 5.

Further include in step 2：While 1 back side of n-type silicon substrate forms passivating back tunnel layer 11, in n-type silicon substrate 1 Front forms front passivation tunnel layer 13.

Further include step before step 3：Overleaf formed on 3 boundary of the second doped region 4 and the first doped region of the back side Area of isolation 10；

In step 3, slot treatment is carried out along the boundary of the back side the second doped region 4 and the first doped region 3 using laser, Groove is formed, completes the passivation to this trench region in the follow-up process so that the second doped region of the back side 4 and the back side first are mixed Area of isolation 10 is formed on 3 boundary of miscellaneous region；Or there are isolated areas between the second doped region 4 and the first doped region 3 The silicon oxide film of 10 shape size of domain not removed, this region form area of isolation 10 during follow-up phosphorus diffusion.

The preferred embodiment that the invention will now be described in detail with reference to the accompanying drawings.

Embodiment 1：

As shown in Figure 1 and Figure 7, a kind of finger-like intersects the structure of back contacts solar cell, and the present embodiment is made using n-type silicon chip For substrate, this battery includes successively from top to bottom：Front passivation and antireflective coating, N-shaped front surface doped layer 12, n-type silicon base Bottom 1, passivating back tunnel layer 11, back side doping film layer 3 and 4, backside passivation film and battery electrode；The wherein back side doping film layer back of the body The first doped region of face 3 and 4 the first doped region of the back side 3 of the second doped region of the back side are by polysilicon, non-crystalline silicon, microcrystal silicon One or more compositions, and adulterate by V group element；The second doped region of the back side 4 is by one in polysilicon, non-crystalline silicon, microcrystal silicon Kind or a variety of compositions, and adulterate by group-III element；

The first doped region of the back side 3 and the second doped region of the back side 4 are staggered in finger-like cross modal, wherein the back side One doped region 3 includes the first pass-through zone 301 and the first vertical area 302, and the second doped region of the back side 4 runs through including second Region 401 and the second vertical area 402；First pass-through zone 301 and the second pass-through zone 401 are mutually parallel；First vertical area Domain 302 and the first pass-through zone 301 are mutually perpendicular to and connect；Second vertical area 402 and the second pass-through zone 401 are mutually perpendicular to And it connects；On 301 direction of the first pass-through zone, the first vertical area 302 and the first vertical area 302 are staggered；

Battery electrode includes positive electrode and negative electrode, and positive electrode includes just superfine grid line 7 and positive connection electrode 9, negative electricity Pole includes the thin grid line 6 of cathode and cathode connection electrode 8；The thin grid line of cathode locally hangs down with the first of the first doped region of the back side 3 Straight region 302 forms contact；Just superfine grid line locally connects with the formation of the second vertical area 402 of the second doped region of the back side 4 It touches；Cathode connection electrode 8 is arranged in the first pass-through zone 301；Positive connection electrode 9 is arranged in the second pass-through zone 401； Just superfine grid line is connect with positive connection electrode 9, and by 9 derived current of positive connection electrode, and the thin grid line of cathode connects with cathode Receiving electrode 8 connects, and passes through negative electrode connection electrode derived current.

Wherein, the width of the first vertical area 302 of the first doped region of the back side 3 is 0.3mm；The second doped region of the back side The width of 4 the second vertical area 402 is 0.5mm.Second vertical area, 402 width and the width of the first vertical area 302 Ratio is 5/3.Wherein, the first pass-through zone 301 of the first doped region of the back side 3 is 3mm；The of the second doped region of the back side 4 The width of two pass-through zones 401 is 4mm.

It is connected between first doped region 3 and the second doped region 4, is not spaced between the two.

Positive passivation and antireflective coating are silicon nitride, refractive index 2.03, thickness 80nm；The passivating film at the back side is oxidation Aluminium is superimposed the laminated construction of silicon nitride, and wherein aluminium oxide thickness is 15nm, silicon nitride thickness 80nm, refractive index of silicon nitride 2.10。

7 line of positive-electrode fine grid is mainly made of silver, and the width of 7 line of positive-electrode fine grid is 30um.Superfine 6 line of grid of negative electricity is main It is made of silver, the width of superfine 6 line of grid of negative electricity is 30um.The connection electrode of positive electrode is 5, and the connection electrode of negative electrode is also 5.The connection electrode of positive electrode connects the institute in this p-type area in the pass-through zone of the second doped region of the above-mentioned back side 4 There is 7 line of positive-electrode fine grid；The connection electrode of negative electrode connects this n in the pass-through zone of the first doped region of the above-mentioned back side 3 Superfine 6 line of grid of all negative electricity in type region.Positive electrode connection electrode is mainly to be made of silver, width 50um, and thickness is 10um, negative electrode connection electrode are mainly to be made of silver, width 50um, thickness 10um.

This method for preparing solar cell, steps are as follows：

1) front surface texturing is carried out to silicon base 1.N-shaped monocrystalline silicon is as battery silicon base 1, using containing the molten of KOH Liquid carries out surface-texturing.KOH solution concentration 5%wt, 80 DEG C of temperature.And it is carried out using the solution for also having hydrofluoric acid in this process Cleaning, and by processes such as washing drying.

2) tunnel layer is formed at 1 back side of n-type silicon substrate.Using silica as the tunnel layer at the N-shaped back side, this oxide layer makes It is grown to be formed with furnace oxidation.Thickness is 1~2nm.

3) local the second doped region 4 and the first doped region are overleaf respectively formed.Use low-pressure chemical vapor deposition Method deposition intrinsic polysilicon layer on the tunneling layer.This intrinsic polysilicon layer thickness is 150nm.Then silk-screen printing boracic is used Doping slurry is coated, and the coating of above-mentioned boron doped slurry, boron doping slurry dispensing area interval occurs, the boron after coating Doping slurry figure forms shape as shown in Figure 1, and boron doping slurry dispensing area includes vertical area and pass-through zone, and Vertical area and pass-through zone are mutually perpendicular to and connect.And the system of the second doped region of the back side 4 is completed by 970 DEG C of thermal diffusions It is standby, and be passed through enough oxygen in thermal diffusion process and aoxidized under the conditions of 970 DEG C, form thicker oxide layer.Then it uses Oxide etch mask carries out part in oxide layer and opens film, and localization reserves the region for waiting for N-shaped doping.Open the figure of diaphragm area The figure of shape and boron doped region is intermeshed, therefore also includes vertical area and pass-through zone.Split diaphragm area is corroded POCl is carried out after cleaning₃Thermal diffusion forms the first doped region of the back side 3.In this POCl₃In diffusion process, tubular diffusion furnace is used It is diffused, and the second doped region of the back side 4 and the back side the first doped region 3 are complete as a result, by above-mentioned silicon chip progress Double side diffusion At graphical distribution, the back side doping knot of the finger-like intersection of the second doped region of the back side 4 and the first doped region of the back side 3 is formed Structure.The POCl in boiler tube₃The thermal diffusion back side formed the first doped region 3 while, due to when Double side diffusion, in n-type silicon 1 front surface of substrate forms N-shaped front surface doped layer 12, this doped layer is front-surface field.

4) front passivated reflection reducing penetrates the preparation of film 2 and backside passivation film.In the removal of the mortise formula cleaning machine through hydrofluoric acid containing After the step of Pyrex and phosphorosilicate glass, deposited in battery front side using enhanced plasma chemical vapor deposition (PECVD) SiNx is as passivation and antireflection layer, thickness 80nm, refractive index 2.03.The back side deposits 5- using atomic layer deposition (ALD) For 10nm aluminium oxide as backside passivation layer 5, bottom reuses the silicon nitride that (PECVD) deposits 70nm thickness on it.

5) use screen printing mode above the second doped region of cell backside 4 and the first doped region of the back of the body table back side 3 The electrode slurry bed of material for including conductive compositions is formed, and completes metallization heat treatment in sintering furnace and forms electrode.At metallization heat 400-750 DEG C of heat spike temperature during reason, it is 650 DEG C preferably to heat peak temperature in the present embodiment.Battery Electrode includes positive electrode and negative electrode, and positive electrode includes just superfine grid line 7 and positive connection electrode 9, and negative electrode includes that cathode is thin Grid line 6 and cathode connection electrode 8；The thin grid line of cathode is contacted with the formation of the first vertical area 302 of the first doped region of the back side 3； Just superfine grid line is contacted with the formation of the second vertical area 402 of the second doped region of the back side 4；The setting of cathode connection electrode 8 is the In one pass-through zone 301；Positive connection electrode 9 is arranged in the second pass-through zone 401；Just superfine grid line and positive connection electrode 9 connections, and by 9 derived current of positive connection electrode, the thin grid line of cathode is connect with cathode connection electrode 8, and passes through negative electrode Connection electrode derived current.

Embodiment 2：

Show as shown in Fig. 2 and Fig. 7, Fig. 8, but front surface doped layer 12 uses p-type as front surface doped layer 12, it is this In the case of, front surface forms floating pn-junction, can also enhance the passivation of front surface.Other structures are similar with the structure of embodiment 1.

This finger-like intersects the structure of back contacts solar cell, and this battery includes successively from top to bottom：Front passivation and Antireflective coating, p-type front surface doped layer 12, n-type silicon substrate 1, passivating back tunnel layer 11, the first doped region of the back side 3 and the back of the body The second doped region of face 4, backside passivation film and battery electrode；The first doped region of the back side 3 is by polysilicon, non-crystalline silicon, microcrystal silicon In one or more compositions, and adulterate by V group element；The second doped region of the back side 4 is by polysilicon, non-crystalline silicon, microcrystal silicon One or more compositions, and adulterate by group-III element；

Wherein, the width of the first vertical area 302 of the first doped region of the back side 3 is 0.2mm；The second doped region of the back side The width of 4 the second vertical area 402 is 1mm.The ratio of second vertical area, 402 width and the width of the first vertical area 302 Value is 5/1.Wherein, the first pass-through zone 301 of the first doped region of the back side 3 is 0.1mm；The of the second doped region of the back side 4 The width of two pass-through zones 401 is 0.1mm.

It is undoped intrinsic more to have area of isolation 10, area of isolation 10 between first doped region 3 and the second doped region 4 Crystal silicon, to completely cut off p-type crystal silicon and n-type crystalline silicon.As shown in Figure 8.

This method for preparing solar cell, steps are as follows：

3) it is overleaf respectively formed local the second doped region 4 and the first doped region 3, and forms front surface p-type and mixes Diamicton.Use low-pressure chemical vapor deposition method deposition intrinsic polysilicon layer on the tunneling layer.This intrinsic polysilicon layer thickness is 150nm.Then it is coated using silk-screen printing boron doped slurry, the coating of above-mentioned boron doped slurry, boron doping slurry Dispensing area interval occurs, and the boron doping slurry figure after coating forms shape as shown in Figure 1, boron doping slurry dispensing area Including vertical area and pass-through zone, and vertical area and pass-through zone are mutually perpendicular to and connect.In 1 front of n-type silicon substrate Print entire boron doping slurry.Above-mentioned semi-finished product are passed through into 970 DEG C of thermal diffusions, complete the preparation of the second doped region of the back side 4, The formation of front surface p-type doped layer 12, and enough dioxygen oxidations are passed through in thermal diffusion progradation, form thicker oxidation Layer, as Pyrex.Then part is carried out in oxide layer using oxide etch mask and opens film, localization, which reserves, waits for n The region of type doping.Wait for N-shaped doping region and between boron-doped region there are certain peak widths 10 not to remove Silicon oxide film, this region become intrinsic polysilicon area of isolation 10 during follow-up phosphorus diffusion.Open diaphragm area figure and The figure of boron doped region is intermeshed, therefore also includes vertical area and pass-through zone.Split diaphragm area carries out corrosion cleaning After carry out POCl₃Thermal diffusion forms the first doped region of the back side 3.In this POCl3 diffusion process, carried out using tubular diffusion furnace Diffusion, and above-mentioned silicon chip is subjected to single side diffusion, 1 two panels of silicon base is inserted into quartz boat face-to-face.The Pyrex of positive and negative As the barrier layer of phosphorus diffusion, the generation of codope phenomenon can be prevented.The second doped region of the back side 4 and the back side first as a result, Doped region 3 is completed graphically to be distributed, and forms the finger-like intersection of the second doped region of the back side 4 and the first doped region of the back side 3 Back side doped structure.And the preparation of front surface doped layer 12 and the system of intrinsic polysilicon area of isolation 10 are completed at this moment It is standby.As shown in Figure 8.

5) use screen printing mode above the second doped region of cell backside 4 and the first doped region of the back of the body table back side 3 The electrode slurry bed of material for including conductive compositions is formed, and completes metallization heat treatment in sintering furnace and forms electrode.At metallization heat 400-750 DEG C of heat spike temperature during reason, it is 650 DEG C preferably to heat peak temperature in the present embodiment.

Embodiment 3：

As shown in Fig. 3, Fig. 7 and Fig. 9, a kind of finger-like intersects the structure of back contacts solar cell, and the present embodiment uses n-type silicon Piece includes successively from top to bottom as substrate, this battery：Front passivation and antireflective coating, N-shaped front surface doped layer 12, N-shaped Silicon base 1, passivating back tunnel layer 11, back side doping film layer 3 and 4, backside passivation film and battery electrode；Wherein back side doping The first doped region of the layer back side 3 and 4 the first doped region of the back side 3 of the second doped region of the back side are by polysilicon, non-crystalline silicon, microcrystal silicon In one or more compositions, and adulterate by V group element；The second doped region of the back side 4 is by polysilicon, non-crystalline silicon, microcrystal silicon One or more compositions, and adulterate by group-III element；

There is area of isolation 10 between first doped region 3 and the second doped region 4, to completely cut off 4 He of the second doped region First doped region 3.As shown in figure 8, area of isolation 10 is intermittent configuration.

This method for preparing solar cell, steps are as follows：

3) local the second doped region 4 and the first doped region are overleaf respectively formed.Use low-pressure chemical vapor deposition Method deposition intrinsic polysilicon layer on the tunneling layer.This intrinsic polysilicon layer thickness is 150nm.Then silk-screen printing boracic is used Doping slurry is coated, and the coating of above-mentioned boron doped slurry, boron doping slurry dispensing area interval occurs, the boron after coating Doping slurry figure forms shape as shown in Figure 7, and boron doping slurry dispensing area includes vertical area and pass-through zone, and Vertical area and pass-through zone are mutually perpendicular to and connect.And the system of the second doped region of the back side 4 is completed by 970 DEG C of thermal diffusions It is standby, and be passed through enough oxygen in thermal diffusion process and aoxidized under the conditions of 970 DEG C, form thicker oxide layer.Then it uses Oxide etch mask carries out part in oxide layer and opens film, and localization reserves the region for waiting for N-shaped doping.Open the figure of diaphragm area The figure of shape and boron doped region is intermeshed, therefore also includes vertical area and pass-through zone.Split diaphragm area is corroded POCl is carried out after cleaning₃Thermal diffusion forms the first doped region of the back side 3.In this POCl₃In diffusion process, tubular diffusion furnace is used It is diffused, and the second doped region of the back side 4 and the back side the first doped region 3 are complete as a result, by above-mentioned silicon chip progress Double side diffusion At graphical distribution, the back side doping knot of the finger-like intersection of the second doped region of the back side 4 and the first doped region of the back side 3 is formed Structure.The POCl in boiler tube₃The thermal diffusion back side formed the first doped region 3 while, due to when Double side diffusion, in n-type silicon 1 front surface of substrate forms N-shaped front surface doped layer 12, this doped layer is front-surface field.

4) area of isolation 10 is formed on 3 boundary of the second doped region of the back side 4 and the first doped region of the back side.Use laser edge The boundary of the second doped region of the back side 4 and n-type region carries out slot treatment, forms groove, is completed in the follow-up process to this ditch The passivation in slot region, as area of isolation 10.Area of isolation 10 is by the second doped region of the back side 4 and the first doped region of the back side 3 It separates.The use of laser power it is 20 watts, wavelength 532nm, spot diameter 30um.As shown in Figure 8.

5) front passivated reflection reducing penetrates the preparation of film 2 and backside passivation film.In the removal of the mortise formula cleaning machine through hydrofluoric acid containing After the step of Pyrex and phosphorosilicate glass, deposited in battery front side using enhanced plasma chemical vapor deposition (PECVD) SiNx is as passivation and antireflection layer, thickness 80nm, refractive index 2.03.The back side deposits 5- using atomic layer deposition (ALD) For 10nm aluminium oxide as backside passivation layer 5, bottom reuses the silicon nitride that (PECVD) deposits 70nm thickness on it.

It is rectangular on the second doped region of cell backside 4 and the first doped region of the back of the body table back side 3 using screen printing mode At the electrode slurry bed of material comprising conductive compositions, and completes metallization heat treatment in sintering furnace and form electrode.Metallization heat treatment 400-750 DEG C of heat spike temperature in the process, it is 650 DEG C preferably to heat peak temperature in the present embodiment.Battery electricity Pole includes positive electrode and negative electrode, and positive electrode includes just superfine grid line 7 and positive connection electrode 9, and negative electrode includes the thin grid of cathode Line 6 and cathode connection electrode 8；The thin grid line of cathode is contacted with the formation of the first vertical area 302 of the first doped region of the back side 3；Just Superfine grid line is contacted with the formation of the second vertical area 402 of the second doped region of the back side 4；Cathode connection electrode 8 is arranged first In pass-through zone 301；Positive connection electrode 9 is arranged in the second pass-through zone 401；Just superfine grid line and positive connection electrode 9 Connection, and by 9 derived current of positive connection electrode, the thin grid line of cathode is connect with cathode connection electrode 8, and is connected by negative electrode Receiving electrode derived current.

Embodiment 4：

As shown in Fig. 4, Fig. 7 and Fig. 8, a kind of finger-like intersects the structure of back contacts solar cell, 12 He of front surface doped layer There is one layer of front passivation tunnel layer 13 between silicon base 1, is adulterated as front surface doped layer 12, in this case, just using N-shaped The p-type doped layer 12 and front passivation tunnel layer 13 in face form the heterogenous pn junction to float in front surface, and positive table can be greatly enhanced The passivation in face.This battery includes successively from top to bottom：Front passivation and antireflective coating, N-shaped front surface doped layer 12, front it is blunt Change tunnel layer 13, n-type silicon substrate 1, passivating back tunnel layer 11, the first doped region of the back side 3 and the second doped region of the back side 4, Backside passivation film and battery electrode；

The first doped region of the back side 3 is made of polysilicon, non-crystalline silicon mixture, and is adulterated by V group element phosphorus；The back side second Doped region 4 is made of polysilicon, non-crystalline silicon mixture, and is adulterated by group-III element boron；

Battery electrode includes positive electrode and negative electrode, and positive electrode includes just superfine grid line 7 and positive connection electrode 9, negative electricity Pole includes the thin grid line 6 of cathode and cathode connection electrode 8；

The thin grid line of cathode is locally contacted with the formation of the first vertical area 302 of the first doped region of the back side 3；Just superfine grid Line is locally contacted with the formation of the second vertical area 402 of the second doped region of the back side 4；Cathode connection electrode 8 is arranged first In pass-through zone 301；Positive connection electrode 9 is arranged in the second pass-through zone 401；Just superfine grid line and positive connection electrode 9 Connection, and by 9 derived current of positive connection electrode, the thin grid line of cathode is connect with cathode connection electrode 8, and is connected by negative electrode Receiving electrode derived current.

There is area of isolation 10 between first doped region 3 and the second doped region 4, to completely cut off 4 He of the second doped region First doped region 3.As shown in Figure 8.

This method for preparing solar cell, steps are as follows：

2) tunnel layer is formed in the front and back of n-type silicon substrate 1.It is passivated 13 He of tunnel layer using silica as front Passivating back tunnel layer 11, this oxide layer grow to be formed using furnace oxidation.Thickness is 1~2nm.

3) it is overleaf respectively formed local the second doped region 4 and the first doped region 3, and N-shaped is formed in front surface Front surface doped layer 12.First, using low-pressure chemical vapor deposition method on front surface tunnel layer and back side tunnelling passivation layer Equal deposition intrinsic polysilicon layer is mixed with portion of amorphous silicon, non-crystalline silicon ratio 2%~7% in this polysilicon layer.This intrinsic polycrystalline Silicon layer thickness is 150nm.Then, it is coated using silk-screen printing boron doped slurry, the coating of above-mentioned boron doped slurry, Boron doping slurry dispensing area interval occurs, and the boron doping slurry figure after coating forms shape as shown in Figure 1, boron doping slurry Expect that dispensing area includes vertical area and pass-through zone, and vertical area and pass-through zone are mutually perpendicular to and connect.And pass through The preparation of the second doped region of the back side 4 is completed in 960 DEG C of thermal diffusions, and in thermal diffusion process, and the two-sided insertion of silicon chip is same Boat tooth is passed through enough dioxygen oxidations, forms thicker oxide layer.Then it is carried out in oxide layer using oxide etch mask Film is opened in part, and localization reserves the region for waiting for N-shaped doping.The figure of the figure and boron doped region of opening diaphragm area is mutually nibbled It closes, therefore also includes vertical area and pass-through zone.Then, this semi-finished product is faced down, is cleaned in chain type hydrofluoric acid single side Machine completes removal and the cleaning process of the oxide layer of front surface.Then, above-mentioned semi-finished product are put into and carry out POCl₃Thermal diffusion shape At the first doped region of the back side 3.In this POCl₃In diffusion process, be diffused using tubular diffusion furnace, and by above-mentioned silicon chip into Row Double side diffusion as a result, complete graphically to be distributed by the second doped region of the back side 4 and the first doped region of the back side 3, forms the back side the The back side doped structure that the finger-like of two doped regions 4 and the first doped region of the back side 3 is intersected.The POCl in boiler tube₃Thermal diffusion is carried on the back Face formed the first doped region 3 while, due to when Double side diffusion, 1 front surface of n-type silicon substrate formed N-shaped front surface Doped layer 12, this doped layer are front-surface field.

4) area of isolation 10 is overleaf formed on 3 boundary of the second doped region 4 and the first doped region of the back side.Use laser Slot treatment is carried out along the boundary of the second doped region of the back side 4 and n-type region, groove is formed, is completed in the follow-up process to this The passivation of trench region, as area of isolation 10.Area of isolation 10 is by the first doped region of the second doped region of the back side 4 and the back side 3 separate.The use of laser power it is 20 watts, wavelength 532nm, spot diameter 30um.

6) use screen printing mode above the second doped region of cell backside 4 and the first doped region of the back of the body table back side 3 The electrode slurry bed of material for including conductive compositions is formed, and completes metallization heat treatment in sintering furnace and forms electrode.At metallization heat 400-750 DEG C of heat spike temperature during reason, it is 650 DEG C preferably to heat peak temperature in the present embodiment.Battery Electrode includes positive electrode and negative electrode, and positive electrode includes just superfine grid line 7 and positive connection electrode 9, and negative electrode includes that cathode is thin Grid line 6 and cathode connection electrode 8；The thin grid line of cathode is locally formed with the first vertical area 302 of the first doped region of the back side 3 Contact；Just superfine grid line is locally contacted with the formation of the second vertical area 402 of the second doped region of the back side 4；Cathode connection electricity Pole 8 is arranged in the first pass-through zone 301；Positive connection electrode 9 is arranged in the second pass-through zone 401；Just superfine grid line with Positive connection electrode 9 connects, and by 9 derived current of positive connection electrode, the thin grid line of cathode is connect with cathode connection electrode 8, And pass through negative electrode connection electrode derived current.

Embodiment 5：

As shown in figure 5 and figure 7, a kind of finger-like intersects the structure of back contacts solar cell, front surface doped layer 12 and silicon substrate There is one layer of front passivation tunnel layer 13 between bottom 1, is adulterated using N-shaped as front surface doped layer 12, it is in this case, positive P-type doped layer 12 and front passivation tunnel layer 13 form the heterogenous pn junction to float in front surface, and front surface can be greatly enhanced Passivation.This battery includes successively from top to bottom：Front passivation and antireflective coating, N-shaped front surface doped layer 12, front passivation tunnel Wear layer 13, n-type silicon substrate 1, passivating back tunnel layer 11, the first doped region of the back side 3 and the second doped region of the back side 4, the back side Passivating film and battery electrode；

Area of isolation 10 is not provided between first doped region 3 and the second doped region 4, the N-shaped of film layer is adulterated at the back side It is connected with p-type.As shown in Figure 6.

This method for preparing solar cell, steps are as follows：

5) use screen printing mode above the second doped region of cell backside 4 and the first doped region of the back of the body table back side 3 The electrode slurry bed of material for including conductive compositions is formed, and completes metallization heat treatment in sintering furnace and forms electrode.At metallization heat 400-750 DEG C of heat spike temperature during reason, it is 650 DEG C preferably to heat peak temperature in the present embodiment.Battery Electrode includes positive electrode and negative electrode, and positive electrode includes just superfine grid line 7 and positive connection electrode 9, and negative electrode includes that cathode is thin Grid line 6 and cathode connection electrode 8；The thin grid line of cathode is locally formed with the first vertical area 302 of the first doped region of the back side 3 Contact；Just superfine grid line is locally contacted with the formation of the second vertical area 402 of the second doped region of the back side 4；Cathode connection electricity Pole 8 is arranged in the first pass-through zone 301；Positive connection electrode 9 is arranged in the second pass-through zone 401；Just superfine grid line with Positive connection electrode 9 connects, and by 9 derived current of positive connection electrode, the thin grid line of cathode is connect with cathode connection electrode 8, And pass through negative electrode connection electrode derived current.

Embodiment 6

As shown in fig. 6, being that front surface doped layer 12 uses p-type doping to be used as front surface doped layer 12, in this case, just The p-type doped layer 12 and front passivation tunnel layer 13 in face form the heterogenous pn junction to float in front surface, and positive table can be greatly enhanced The passivation in face.This finger-like intersects the structure of back contacts solar cell, and this battery includes successively from top to bottom：Front passivation and Antireflective coating, p-type front surface doped layer 12, p-type front passivation tunnelling once 13, n-type silicon substrate 1, passivating back tunnel layer 11, the back of the body The first doped region of face 3 and the second doped region of the back side 4, backside passivation film 5 and battery electrode；The first doped region of the back side 3 by One or more compositions in polysilicon, non-crystalline silicon, microcrystal silicon, and adulterate by V group element phosphorus；The second doped region of the back side 4 by One or more compositions in polysilicon, non-crystalline silicon, microcrystal silicon, and adulterate by group-III element boron；

Wait for N-shaped doping region and between boron-doped region there are certain peak widths 10 not to remove silicon Film, this region become intrinsic polysilicon area of isolation 10 during follow-up phosphorus diffusion.This area of isolation 10 is in the first doping Exist on the segment boundary of region 3 and the second doped region 4, be not present on segment boundary so that the N-shaped doping of subregion is brilliant Silicon layer and p-type doping crystal silicon layer keep apart, to reduce subregion drain conditions generation.As shown in Figure 9.

This method for preparing solar cell, steps are as follows：

3) it is overleaf respectively formed local the second doped region 4 and the first doped region 3, and forms front surface p-type and mixes Diamicton.Use low-pressure chemical vapor deposition method deposition intrinsic polysilicon layer on the tunneling layer.This intrinsic polysilicon layer thickness is 150nm.Then it is coated using silk-screen printing boron doped slurry, the coating of above-mentioned boron doped slurry, boron doping slurry Dispensing area interval occurs, and the boron doping slurry figure after coating forms shape as shown in Figure 7, boron doping slurry dispensing area Including vertical area and pass-through zone, and vertical area and pass-through zone are mutually perpendicular to and connect.In 1 front of n-type silicon substrate Print entire boron doping slurry.Above-mentioned semi-finished product are passed through into 970 DEG C of thermal diffusions, complete the preparation of the second doped region of the back side 4, The formation of front surface p-type doped layer 12, and enough dioxygen oxidations are passed through in thermal diffusion progradation, form thicker oxidation Layer, as Pyrex.Then part is carried out in oxide layer using oxide etch mask and opens film, localization, which reserves, waits for n The region of type doping.Wait for N-shaped doping region and between boron-doped region there are certain peak widths 10 not to remove Silicon oxide film, this region become intrinsic polysilicon area of isolation 10 during follow-up phosphorus diffusion.Open diaphragm area figure and The figure of boron doped region is intermeshed, therefore also includes vertical area and pass-through zone.Split diaphragm area carries out corrosion cleaning After carry out POCl₃Thermal diffusion forms the first doped region of the back side 3.In this POCl₃In diffusion process, carried out using tubular diffusion furnace Diffusion, and above-mentioned silicon chip is subjected to single side diffusion, 1 two panels of silicon base is inserted into quartz boat face-to-face.The Pyrex of positive and negative As the barrier layer of phosphorus diffusion, the generation of codope phenomenon can be prevented.The second doped region of the back side 4 and the back side first as a result, Doped region 3 is completed graphically to be distributed, and forms the finger-like intersection of the second doped region of the back side 4 and the first doped region of the back side 3 Back side doped structure.And the preparation of front surface doped layer 12 is completed at this moment.And front surface doped layer 12 is completed at this moment Preparation and intrinsic polysilicon area of isolation 10 preparation.

Similarly, the passivation film in above example can replace with accordingly silicon nitride, silicon oxynitride, silicon carbide, The structure of matter of the phases same-action such as non-crystalline silicon.In the above-described embodiments, it is provided with area of isolation 10, can increase by the second doping The isolation effect in region 4 and the first doped region 3, the step of this area of isolation 10 can not also be set and prepare this region, together Sample can also form complete battery structure and technical solution, only can slightly reduce isolation effect, therefore do not repeat, such scheme Also in our scheme of the invention.

In addition, the above embodiment of the present invention is embodiment, there is the technological thought with claims of the present invention It is allowed to identical method and plays the technical solution of identical function and effect, be all contained in the present invention.

Claims

1. a kind of finger-like with passivation contact structures intersects back contacts solar cell, which is characterized in that along silicon base (1) thickness Direction includes successively from top to bottom：Front passivation and antireflective coating (2), front doped layer (12), n-type silicon substrate (1), the back side are blunt Change tunnel layer (11), back side doped layer, backside passivation film (5) and battery electrode；The back side doped layer is by the first doped region (3) it is formed with the second doped region (4), the first doped region (3) and the second doped region (4) finger-like cross arrangement；Described Battery electrode includes positive electrode and negative electrode；

First doped region (3) includes the first pass-through zone (301) and the first vertical area (302), second doping Region (4) includes the second pass-through zone (401) and the second vertical area (402)；First pass-through zone (301) and second runs through area Domain (401) is mutually parallel；First vertical area (302) and the first pass-through zone (301) are mutually perpendicular to and connect；Described Two vertical areas (402) and the second pass-through zone (401) are mutually perpendicular to and connect；On the first pass-through zone (301) direction, the One vertical area (302) and the second vertical area (402) are staggered；

The positive electrode includes just superfine grid line (7) and positive connection electrode (9), and the negative electrode includes the thin grid line of cathode (6) With cathode connection electrode (8)；The thin grid line of cathode (6) is contacted with the formation of the first vertical area (302) of the first doped region (3)； Just superfine grid line (7) contacts with the formation of the second vertical area (402) of the second doped region (4)；Cathode connection electrode (8) is arranged In the first pass-through zone (301)；Positive connection electrode (9) setting is in the second pass-through zone (401)；Just superfine grid line (7) Connected with positive connection electrode (9), and by positive connection electrode (9) derived current, negative electrode include the thin grid line of cathode (6) and Cathode connection electrode (8) connects, and passes through cathode connection electrode (8) derived current.

2. the finger-like with passivation contact structures according to claim 1 intersects back contacts solar cell, which is characterized in that At least partly there are area of isolation between the second doped region of the first doped region of the back side and the back side, width is 2~ 200um。

3. the finger-like with passivation contact structures according to claim 1 intersects back contacts solar cell, which is characterized in that One of the width of one the second vertical area (402) of second doped region (4) and adjacent first doped region (3) the The sum of width of one vertical area (302) is 0.2~5mm, wherein the width and the first vertical area of the second vertical area (402) (302) width ratio is 1~20.

4. the finger-like with passivation contact structures according to claim 1 intersects back contacts solar cell, which is characterized in that The first pass-through zone (301) width of first doped region (3) is 0.08~5mm；The of second doped region (4) The width of two pass-through zones (401) is 0.08~5mm.

5. the finger-like with passivation contact structures according to claim 1 intersects back contacts solar cell, which is characterized in that The just superfine grid line (7) is made of one or more in silver, aluminium, copper or nickel, the width of just superfine grid line (7) be 20um~ 200um；The thin grid line of cathode (6) is made of silver, one or more in copper and mickel, and the width of the thin grid line of cathode (6) is 20um~200um.

6. the finger-like according to claim 1 with area of isolation intersects back contacts solar cell, which is characterized in that described Positive connection electrode (9) and cathode connection electrode (8) are made of one or more in silver, copper, aluminium or nickel；The anode is even Receiving electrode (9) is 1-40 roots, and the cathode connection electrode (8) is 1-40 roots.

7. the finger-like with passivation contact structures according to claim 1 intersects back contacts solar cell, which is characterized in that The front passivation and antireflective coating (2), using in silicon nitride, silica, silicon oxynitride, aluminium oxide, silicon carbide, non-crystalline silicon One or more compositions；The passivating film at the back side, using silicon nitride, silica, silicon oxynitride, aluminium oxide, silicon carbide, amorphous One or more compositions in silicon.

8. the finger-like with passivation contact structures according to claim 1 intersects back contacts solar cell, which is characterized in that The passivating back tunnel layer is one in intrinsic amorphous silicon, silicon nitride, silica, silicon oxynitride, aluminium oxide, silicon carbide Kind.

9. the finger-like with passivation contact structures according to claim 1~8 any one intersects back contacts solar cell, It is characterized in that, the front surface doped layer is n-type silicon substrate homogeneity doped layer, the n-type silicon substrate homogeneity doped layer is mixed Miscellaneous have a V group element, and doping concentration is 1 × 10¹⁷~5 × 10²¹cm^-3。

10. according to claim 1~8 any one there is the finger-like of passivation contact structures to intersect back contacts sun electricity Pond, which is characterized in that the front surface doped layer is p-type silicon substrate homogeneity doped layer, the p-type silicon substrate homogeneity doped layer Doped with group-III element, doping concentration is 1 × 10¹⁷~5 × 10²¹cm^-3。

11. according to claim 1~8 any one there is the finger-like of passivation contact structures to intersect back contacts sun electricity Pond, which is characterized in that the front surface doped layer is the heterogeneous doping film layer of N-shaped, and the heterogeneous doping film layer of N-shaped is close to N-shaped Silicon base side includes that one layer of front is passivated tunnel layer；The front passivation tunnel layer is non-crystalline silicon, silicon nitride, silica, nitrogen One kind in silica, aluminium oxide, silicon carbide；The heterogeneous doping film layer of p-type is by one in polysilicon, non-crystalline silicon, microcrystal silicon Kind or a variety of compositions, and doped with V group element, doping concentration is 1 × 10¹⁷~5 × 10²¹cm^-3。

12. according to claim 1~8 any one there is the finger-like of passivation contact structures to intersect back contacts sun electricity Pond, which is characterized in that the front surface doped layer is the heterogeneous doping film layer of p-type；The heterogeneous doping film layer of p-type is close to N-shaped Silicon base side includes that one layer of front is passivated tunnel layer；The front passivation tunnel layer is non-crystalline silicon, silicon nitride, silica, nitrogen One kind in silica, aluminium oxide, silicon carbide；The heterogeneous doping film layer of p-type is by one in polysilicon, non-crystalline silicon, microcrystal silicon Kind or a variety of compositions, and doped with group-III element, doping concentration is 1 × 10¹⁷~5 × 10²¹cm^-3。

13. a kind of preparation method that there is the finger-like of passivation contact structures to intersect back contacts solar cell, which is characterized in that including Following steps：

1) surface-texturing is carried out to n-type silicon substrate (1) front；

2) passivating back tunnel layer (11) is formed at n-type silicon substrate (1) back side；Again in n-type silicon substrate (1) back-patterned formation Second doped region (4) and the first doped region (3) so that the first doped region (3) and the second doped region (4) are handed in finger-like Fork-shaped formula is staggered；N-type surface doped layer or p-type front surface doped layer are prepared in silicon base (1) front；

3) again n-type silicon substrate (1) back side prepare backside passivation film (5), n-type silicon substrate (1) front prepare front passivation and Antireflective coating (2)；

4) overleaf battery electrode is prepared on passivating film (5).

14. the preparation side according to claim 13 that there is the finger-like of passivation contact structures to intersect back contacts solar cell Method, which is characterized in that further include in step 2)：While n-type silicon substrate (1) back side forms passivating back tunnel layer (11), Front passivation tunnel layer (13) is formed in n-type silicon substrate (1) front.

15. the preparation side according to claim 13 that there is the finger-like of passivation contact structures to intersect back contacts solar cell Method, which is characterized in that further include step before step 3)：Overleaf the second doped region (4) and the first doped region of the back side (3) Area of isolation (10) is formed on boundary.

16. the preparation side according to claim 13 that there is the finger-like of passivation contact structures to intersect back contacts solar cell Method, which is characterized in that in step 4), positive electrode is contacted with the second doped region (4), and negative electrode connects with the first doped region (3) It touches, contact of the electrode with doped region is burnt backside passivation film (5) formation using electrode slurry and be in direct contact, or passes through setting It is pre- to open diaphragm area and be in direct contact opening diaphragm area formation in advance.