CN104471718A

CN104471718A - Solar cell element, production method for solar cell element, and solar cell module

Info

Publication number: CN104471718A
Application number: CN201380038079.0A
Authority: CN
Inventors: 织田明博; 吉田诚人; 野尻刚; 仓田靖; 田中彻; 足立修一郎; 早坂刚; 服部孝司; 松村三江子; 渡边敬司; 森下真年; 滨村浩孝
Original assignee: Hitachi Chemical Co Ltd
Current assignee: Showa Denko Materials Co ltd
Priority date: 2012-07-19
Filing date: 2013-07-19
Publication date: 2015-03-25
Also published as: TW201408600A; JPWO2014014111A1; TWI609838B; WO2014014111A1; JP6350278B2

Abstract

This solar cell element is provided with: a semiconductor substrate having a light-receiving surface, a rear surface located on the opposite side to the light-receiving surface, and a side surface; a light-receiving-surface electrode provided on the light-receiving surface; a rear surface electrode provided on the rear surface; and a passivation layer which is provided on at least one from among the light-receiving surface, the rear surface, and the side surface, and which includes at least one compound selected from the group consisting of Nb2O5, Ta2O5, V2O5, Y2O3, and HfO2.

Description

The manufacture method of solar cell device, solar cell device and solar module

Technical field

The present invention relates to solar cell device, the manufacture method of solar cell device and solar module.

Background technology

The manufacturing process of silicon solar cell element is in the past described.

First, in order to promote that sunken luminous effect realizes high efficiency, prepare the p-type silicon substrate being formed with texture structure in sensitive surface side, then, at phosphorous oxychloride (POCl ₃), at 800 DEG C ~ 900 DEG C, carry out the process of several tens minutes in the mixed-gas atmosphere of nitrogen and oxygen, be formed uniformly n-type diffusion layer.In this method in the past, due to the diffusion using mist to carry out phosphorus, therefore not only form n-type diffusion layer on sensitive surface i.e. surface, and also form n-type diffusion layer in side and the back side.Therefore, in order to remove the n-type diffusion layer that is formed at side and need to carry out lateral erosion quarter.In addition, the n-type diffusion layer being formed at the back side needs to be transformed to p ⁺type diffusion layer.Therefore, comprise the Aluminum Paste of aluminum particulate and adhesive at whole backsize and (burning till) heat-treated to it and n-type diffusion layer is converted into p ⁺type diffusion layer, and form aluminium electrode, obtain ohmic contact thus.

But the conductivity of the aluminium electrode formed by Aluminum Paste is low.Therefore, in order to reduce film resistor, the aluminium electrode being usually formed at the whole back side must have the thickness of 10 μm ~ about 20 μm after heat treatment.And then, because the coefficient of thermal expansion of silicon and aluminium differs widely, therefore, in the process of heat treatment and cooling, make to be formed in the silicon substrate of aluminium electrode and produce larger internal stress, thus cause grain boundary damage (damage), crystal defect to increase and warpage.

In order to solve this problem, there is the imparting amount that reduces Aluminum Paste and making the method for the lower thickness of aluminium electrode.But, if reduce the imparting amount of Aluminum Paste, then become insufficient from the diffusion into the surface of p-type silicon semiconductor substrate to the aluminum amount of inside.Result: required BSF (Back SurfaceField, back surface field) effect cannot be realized (because of p ⁺the existence of type diffusion layer and make the effect that the collection efficiency of generation charge carrier improves), the problem that the characteristic therefore producing solar cell reduces.

Based on above-mentioned situation, propose by giving Aluminum Paste in a part for silicon substrate and be formed locally p ⁺the method (such as with reference to Japan Patent No. 3107287 publication) of the point cantact of type diffusion layer and aluminium electrode.

This kind, when the face (hereinafter also referred to " back side ") contrary with sensitive surface has the solar cell of point cantact structure, needs the recombination velocity suppressing minority carrier on the surface of the part except aluminium electrode.As the passivation layer at the back side for this purposes, propose SiO ₂film etc. (such as with reference to Japanese Unexamined Patent Publication 2004-6565 publication).As because forming this kind of SiO ₂the passivation effect that film produces, comprises the non-associative key end-blocking of the silicon atom in the back surface layer portion of silicon substrate, thus makes the effect causing the surface level density reduction combined again.

In addition, as suppressing other method combined again of minority carrier, comprise utilize the fixed charge in passivation layer to produce electric field to reduce the method for minority carrier density.Such passivation effect is commonly called field effect, and proposes aluminium oxide (Al ₂o ₃) film etc. is as the material (such as with reference to Japan Patent No. 4767110 publication) with negative fixed charge.

Such passivation layer is usually by ALD (Atomic Layer Deposition, ald) method, CVD (Chemical Vapor Deposition, chemical vapour deposition (CVD)) method such as method forms (such as with reference to Journal of Applied Physics, 104 (2008), 113703-1 ~ 113703-7).In addition, as the easy method forming pellumina on a semiconductor substrate, propose method (the such as reference Thin Solid Films utilizing sol-gal process, 517 (2009), 6327 ~ 6330 and Chinese Physics Letters, 26 (2009), 088102-1 ~ 088102-4).

Summary of the invention

The problem that invention will solve

Journal of Applied Physics, the method recorded in 104 (2008), 113703-1 ~ 113703-7 comprises the manufacturing process of the complexity such as evaporation, so there is the situation being difficult to boost productivity.In addition, for Thin Solid Films, 517 (2009), 6327-6330 and Chinese PhysicsLetters, 26 (2009), in the passivation layer formation composition of the method described in 088102-1 ~ 088102-4, can produce the unfavorable conditions such as gelation in time dependent ground, storage stability is also difficult to deserve to be called abundant.

The present invention completes in view of above problem in the past, and its problem is to provide has excellent conversion efficiency and the easy manufacture method of the solar cell device suppressing the time dependent of conversion efficiency to reduce, this solar cell device and solar module.

For solving the means of problem

Concrete means for solving above-mentioned problem are as described below.

<1> solar cell device, it has:

Have sensitive surface, with the above-mentioned back side of sensitive surface opposition side and the semiconductor substrate of side;

Be configured at the sensitive surface electrode on above-mentioned sensitive surface;

Be configured at the backplate on the above-mentioned back side; With

To be configured at least one face in above-mentioned sensitive surface, the above-mentioned back side and above-mentioned side and containing being selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃and HfO ₂in the passivation layer of at least a kind of compound.

The solar cell device of <2> according to above-mentioned <1>, wherein, above-mentioned passivation layer is also containing Al ₂o ₃.

The solar cell device of <3> according to above-mentioned <1> or <2>, wherein, above-mentioned passivation layer is the heat treatment thing of passivation layer formation composition.

The solar cell device of <4> according to above-mentioned <3>, wherein, above-mentioned passivation layer formation composition contains and is selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃, HfO ₂and at least a kind of compound in the compound shown in following general formula (I).

M(OR ¹) _m(I)

In formula (I), M comprises at least a kind of metallic element be selected from Nb, Ta, V, Y and Hf.R ¹separately represent the alkyl of carbon number 1 ~ 8 or the aryl of carbon number 6 ~ 14.M represents the integer of 0 ~ 5.

The solar cell device of <5> according to above-mentioned <4>, wherein, above-mentioned passivation layer formation composition contains and is selected from Nb ₂o ₅and the M in above-mentioned general formula (I) is at least a kind of niobium compound in the compound of Nb, total containing ratio of the above-mentioned niobium compound in above-mentioned passivation layer formation composition is with Nb ₂o ₅be scaled 0.1 quality % ~ 99.9 quality %.

The solar cell device of <6> according to any one of above-mentioned <3> ~ <5>, wherein, above-mentioned passivation layer formation composition is also containing being selected from Al ₂o ₃and at least a kind of aluminium compound in the compound shown in following general formula (II).

[changing 1]

In formula (II), R ²separately represent the alkyl of carbon number 1 ~ 8.N represents the integer of 0 ~ 3.X ²and X ³separately represent oxygen atom or methylene.R ³, R ⁴and R ⁵separately represent the alkyl of hydrogen atom or carbon number 1 ~ 8.

The solar cell device of <7> according to above-mentioned <6>, wherein, the R in above-mentioned general formula (II) ²it is separately the alkyl of carbon number 1 ~ 4.

The solar cell device of <8> according to above-mentioned <6> or <7>, wherein, the n in above-mentioned general formula (II) is integer, the R of 1 ~ 3 ⁵it is separately the alkyl of hydrogen atom or carbon number 1 ~ 4.

The solar cell device of <9> according to any one of above-mentioned <6> ~ <8>, wherein, above-mentioned passivation layer formation composition comprises and is selected from Al ₂o ₃and at least a kind of aluminium compound in the compound shown in above-mentioned general formula (II), the containing ratio of the above-mentioned aluminium compound in above-mentioned passivation layer formation composition is 0.1 quality % ~ 80 quality %.

The solar cell device of <10> according to any one of above-mentioned <3> ~ <9>, wherein, above-mentioned passivation layer formation composition is also containing liquid medium.

The solar cell device of <11> according to above-mentioned <10>, wherein, above-mentioned liquid medium comprises at least a kind that is selected from hydrophobic organic solvent, non-proton organic solvent, terpene solvent, ester solvent, ether solvents and alcoholic solvent.

The manufacture method of the solar cell device according to any one of <12> above-mentioned <1> ~ <11>, it comprises:

The operation of sensitive surface electrode is formed at the sensitive surface of semiconductor substrate;

The operation of backplate is formed in the face contrary with above-mentioned sensitive surface of above-mentioned semiconductor substrate and the back side;

Passivation layer formation composition is given at least one face in above-mentioned sensitive surface, the above-mentioned back side and side and forms the operation of composition layer, described passivation layer formation composition contains and is selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃, HfO ₂and at least a kind of compound in the compound shown in following general formula (I); With

Combinations thereof nitride layer is heat-treated and forms the operation of passivation layer.

M(OR ¹) _m(I)

The manufacture method of the solar cell device of <13> according to above-mentioned <12>, wherein, above-mentioned passivation layer formation composition is also containing being selected from Al ₂o ₃and at least a kind of aluminium compound in the compound shown in following general formula (II).

[changing 2]

The manufacture method of the solar cell device of <14> according to above-mentioned <12> or <13>, wherein, above-mentioned heat treated temperature is more than 400 DEG C.

The manufacture method of the solar cell device of <15> according to any one of above-mentioned <12> ~ <14>, wherein, the operation of above-mentioned formation composition layer comprises the step utilizing silk screen print method or ink-jet method to give above-mentioned passivation layer formation composition.

<16> solar module, its wiring material that there is the solar cell device according to any one of above-mentioned <1> ~ <11> and be configured on the electrode of above-mentioned solar cell device.

Invention effect

According to the present invention, can provide and there is excellent conversion efficiency and the easy manufacture method of the solar cell device that the time dependent of conversion efficiency can be suppressed to reduce, this solar cell device and solar module.

Accompanying drawing explanation

Fig. 1 is the cutaway view with an example of the manufacture method of the solar cell device of passivation layer schematically showing present embodiment.

Fig. 2 is the cutaway view with another example of the manufacture method of the solar cell device of passivation layer schematically showing present embodiment.

Fig. 3 schematically shows the printed patterns of passivation layer formation composition of embodiment and the vertical view of the printed patterns of aluminium electrode.

Fig. 4 is the vertical view of the printed patterns of the silver electrode schematically showing embodiment.

Fig. 5 is the cutaway view of the structure representing double-face electrode type solar cell device.

Fig. 6 is the cutaway view of the 1st configuration example of the solar cell device representing reference implementation mode.

Fig. 7 is the cutaway view of the 2nd configuration example of the solar cell device representing reference implementation mode.

Fig. 8 is the cutaway view of the 3rd configuration example of the solar cell device representing reference implementation mode.

Fig. 9 is the cutaway view of the 4th configuration example of the solar cell device representing reference implementation mode.

Figure 10 is the cutaway view of another configuration example of the solar cell device representing reference implementation mode.

Embodiment

In this manual, independently operation be not only in term " operation ", but also have the situation that clearly cannot be different from other operation, as long as can realize the expection object of this operation in this case, is then also contained in this term.In addition, the numerical value using " ~ " number range of illustrating to represent in this specification to record the front and back containing " ~ " is respectively as the scope of minimum value and maximum.And then, about the content of each composition in the composition of this specification, exist multiple when being equivalent to the material of each composition in the composition, unless otherwise specified, then all refer to the total amount of this many kinds of substance existed in composition.In addition, term " layer " in this manual, except being formed at the formation of the shape of whole when comprising and observe in top plan view, also comprises the formation of the shape being formed at a part when observing in top plan view.

< solar cell device >

Solar cell device of the present invention has: have sensitive surface, with the above-mentioned back side of sensitive surface opposition side and the semiconductor substrate of side; Be configured at the sensitive surface electrode on above-mentioned sensitive surface; Be configured at the backplate on the above-mentioned back side; To be configured at least one face in above-mentioned sensitive surface, the above-mentioned back side and above-mentioned side and containing being selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃and HfO ₂in the passivation layer of at least a kind of compound (below also referred to as " special metal oxide ", and by the metallic element contained by each special metal oxide also referred to as " special metal element ").Solar cell device can have other inscape as required further.

At least one mask in the sensitive surface of semiconductor substrate, the back side and side has the conversion efficiency of the solar cell device of the passivation layer containing special metal oxide excellent and the time dependent of conversion efficiency is by the time reduced and is inhibited.Think that its reason is such as: by making passivation layer contain special metal oxide, thus embody excellent passivation effect, and make the carrier lifetime in semiconductor substrate elongated, therefore, it is possible to realize high efficiency.In addition, think that its reason is also: by having the above-mentioned passivation layer containing special metal oxide, thus passivation effect can be maintained, and the time dependent of conversion efficiency can be suppressed to reduce.At this, the reduction of characteristic of solar cell by the time can utilize the characteristic of solar cell place the stipulated time in constant temperature and humidity cabinet after to evaluate.

The passivation layer containing special metal oxide about at least one face in the sensitive surface of semiconductor substrate, the back side and side has the reason of excellent passivation effect, can consider as follows.Namely think: by the passivation layer containing special metal oxide being arranged on the surface of semiconductor substrate, thus due to the special metal element in special metal oxide or oxygen atom defect etc. and there is fixed charge at the near interface with semiconductor substrate.This fixed charge produces electric field at the near interface of semiconductor substrate, can produce band curvature thus and reduce the concentration of minority carrier.Result is thought: because the charge carrier recombination velocity on interface is inhibited, and has therefore given play to excellent passivation effect.

The fixed charge that special metal oxide has can utilize CV method (CapacitanceVoltage Measurement, capacitance voltage mensuration) to evaluate.If the surface level density of heat-treating formed passivation layer to passivation layer formation composition described later is utilized CV method to evaluate, then its value is greater than the passivation layer utilizing ALD method or CVD to be formed sometimes.But the large and concentration of minority carrier of the field effect of the passivation layer that solar cell device of the present invention has reduces, and makes τ surface lifetime _sbecome large.Therefore, surface level density is not a problem comparatively speaking.

In this specification, the devices such as the WT-2000PVN using Japanese Shi Meilebo Co., Ltd. to manufacture, utilize the useful life of Photoconductivity decay by microwave reflectance damped method to the minority carrier be formed in the semiconductor substrate of passivation layer to measure, the passivation effect of semiconductor substrate can be evaluated thus.

At this, useful life τ can utilize bulk lifetime (bulk lifetime) τ of semiconductor-based intralamellar part like that according to following formula (A) _bwith τ surface lifetime of semiconductor substrate surface _srepresent.When the surface level density of semiconductor substrate surface is little, τ _selongated, result makes useful life τ elongated.In addition, even if the defects such as the dangling bonds of semiconductor-based intralamellar part tail off, bulk lifetime τ _balso can be elongated, make useful life τ also elongated.That is, the bulk properties of the semiconductor substrates such as the interfacial characteristics of passivation layer and semiconductor substrate and dangling bonds can be evaluated by measuring useful life τ.

1/τ＝1/τ _b+1/τ _s(A)

In addition, useful life is longer, represents that the recombination velocity of minority carrier is slower.In addition, by using the long semiconductor substrate of useful life to form solar cell device, thus conversion efficiency is improved.

Solar cell device comprises the semiconductor substrate with sensitive surface and the back side with above-mentioned sensitive surface opposition side.There is no particular restriction for semiconductor substrate, suitably can select according to object from usual used semiconductor substrate.As semiconductor substrate, can be set forth in doping (diffusion) in silicon, germanium etc. has the semiconductor substrate of p-type impurity or N-shaped impurity.Wherein, silicon substrate is preferably.In addition, semiconductor substrate both can be p-type semiconductor substrate, also can be n-type semiconductor substrate.Wherein, from the view point of passivation effect, be preferably the semiconductor substrate that the face (at least one face namely in sensitive surface, the back side and side) forming passivation layer is p-type layer.P-type layer on semiconductor substrate both can be the p-type layer deriving from p-type semiconductor substrate, also can be with p-diffusion layer or p ⁺the form of type diffusion layer is formed at the p-type layer on n-type semiconductor substrate or p-type semiconductor substrate.

In above-mentioned semiconductor substrate, preferably p-type layer and n-layer are carried out pn joint.That is, when semiconductor substrate is p-type semiconductor substrate, preferably in sensitive surface or the back side formation n-layer of semiconductor substrate.In addition, when semiconductor substrate is n-type semiconductor substrate, preferably in sensitive surface or the back side formation p-type layer of semiconductor substrate.The method forming p-type layer or n-layer at semiconductor substrate is not particularly limited, and suitably can select from usual used method.

There is no particular restriction for the thickness of semiconductor substrate, suitably can select according to object.The thickness of such as semiconductor substrate can be set to 50 μm ~ 1000 μm, is preferably 75 μm ~ 750 μm.Unrestricted for the shape of semiconductor substrate and size, such as can be set to the square that the length of side is 125mm ~ 156mm.

Solar cell device of the present invention has and is configured at sensitive surface electrode on sensitive surface and is configured at and the backplate on the back side of the sensitive surface opposition side of semiconductor substrate.Sensitive surface electrode such as has the function of aggregate current on the sensitive surface of semiconductor substrate.Backplate such as has function electric current being exported to outside.

There is no particular restriction for the material of sensitive surface electrode, can enumerate silver, copper, aluminium etc.The thickness of sensitive surface electrode is not particularly limited, and from conductivity and homogeneous viewpoint, is preferably 0.1 μm ~ 50 μm.

There is no particular restriction for the material of backplate, can enumerate silver, copper, aluminium etc.From forming backplate and making aluminium atoms permeating to semiconductor substrate and form p ⁺the viewpoint of type diffusion layer is set out, and the material of backplate is preferably aluminium.There is no particular restriction for the thickness of backplate, from the view point of the warpage of conductivity and substrate, is preferably 0.1 μm ~ 50 μm.

Sensitive surface electrode and backplate can utilize the method usually used to manufacture.Such as sensitive surface electrode and backplate can by giving the electrode formation pastes such as silver-colored paste, Aluminum Paste, copper paste and heat-treating (burning till) to manufacture to it as required at the desired zone of semiconductor substrate.

Solar cell device of the present invention at least one face in the sensitive surface of semiconductor substrate, the back side and side has the passivation layer containing special metal oxide.And then above-mentioned passivation layer can contain Al ₂o ₃.Passivation layer can be arranged on the part at least one face above-mentioned or whole, but is preferably arranged on region except for the electrodes.In addition, electrode can have the part overlapping with passivation layer to be formed.

There is no particular restriction for the average thickness of formation passivation layer on a semiconductor substrate, suitably can select according to object.Such as, from the view point of passivation effect, the average thickness of passivation layer is preferably 5nm ~ 50 μm, is more preferably 10nm ~ 30 μm, more preferably 15nm ~ 20 μm.At this, the average thickness of passivation layer is by using interfere type film thickness gauge (FILMETRICS company, F20 determining film thickness system) and conventionally measuring the thickness of 5, calculate its arithmetic mean to calculate again.

From the view point of obtaining sufficient passivation effect, the containing ratio of special metal oxide contained in passivation layer is preferably 0.1 quality % ~ 100 quality %, is more preferably 1 quality % ~ 100 quality %, more preferably 10 quality % ~ 100 quality %.

The containing ratio of special metal oxide contained in passivation layer can measure in accordance with the following methods.That is, use atomic absorption spectroscopy, ICP emission spectrometry, thermogravimetry, X ray Photoelectron Spectroscopy etc., and calculated the ratio of inorganic matter by thermogravimetry.Then, utilize atomic absorption spectroscopy, ICP emission spectrometry etc. to calculate the ratio of the compound of the special metal element in inorganic matter, and utilize X ray Photoelectron Spectroscopy, X ray absorption spectrometry etc. to calculate the ratio of the special metal oxide in the compound of special metal element.

Passivation layer can comprise other inorganic oxide except special metal oxide further.As other inorganic oxide, preferably there is the compound of fixed charge, specifically, aluminium oxide can be enumerated, silica, titanium oxide, gallium oxide, zirconia, boron oxide, indium oxide, phosphorous oxide, zinc oxide, lanthana, praseodymium oxide, neodymia, promethium oxide, samarium oxide, europium oxide, gadolinium oxide, terbium oxide, dysprosia, holimium oxide, erbium oxide, thulium oxide, ytterbium oxide, luteium oxide etc., from the view point of the height of passivation effect, preferably be selected from silica, titanium oxide, zirconia, at least a kind in neodymia and aluminium oxide, more preferably at least containing aluminium oxide.

The containing ratio of other inorganic oxide in passivation layer is preferably below 80 quality %, is more preferably below 60 quality %.The containing ratio of other inorganic oxide contained in passivation layer can measure in the same manner as the assay method of the containing ratio of above-mentioned special metal oxide.

From the view point of the ageing stability of passivation effect, the density of passivation layer is preferably 1.0g/cm ³~ 8.0g/cm ³, be more preferably 2.0g/cm ³~ 6.0g/cm ², more preferably 3.0g/cm ³~ 5.0g/cm ³.

The density of passivation layer is calculated by the area of passivation layer and the quality of thickness and passivation layer.Specifically, the density of passivation layer can use pressure suspension method or temperature suspension method to measure.

< passivation layer is formed and uses composition >

The passivation layer of solar cell device of the present invention is preferably the heat treatment thing of passivation layer formation composition.As long as above-mentioned passivation layer formation composition can form the composition of the passivation layer containing special metal oxide by heat-treating (burning till), then there is no particular restriction, can special metal oxide itself be contained, also can containing the precursor that can become special metal oxide.Below, by special metal oxide and precursor thereof also referred to as special metal compound.

From the view point of the height of passivation effect, passivation layer formation composition preferably comprises and is selected from above-mentioned special metal oxide (Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃and HfO ₂) and as the above-mentioned precursor of special metal oxide following general formula (I) shown in compound (below also referred to as formula (I) compound) at least a kind of compound.

M(OR ¹) _m(I)

In general formula (I), R ¹separately represent the alkyl of carbon number 1 ~ 8 or the aryl of carbon number 6 ~ 14, be preferably the alkyl of carbon number 1 ~ 8, be more preferably the alkyl of carbon number 1 ~ 4.R ¹shown alkyl both can be straight-chain, also can be branched.As R ¹shown alkyl, specifically, can enumerate methyl, ethyl, propyl group, isopropyl, butyl, isobutyl group, sec-butyl, the tert-butyl group, hexyl, octyl group, 2-ethylhexyl etc.As R ¹shown aryl, specifically, can enumerate phenyl.

R ¹shown alkyl and aryl can have substituting group.As the substituting group of alkyl, halogen atom, amino, hydroxyl, carboxyl, sulfo group, nitro etc. can be enumerated.As the substituting group of aryl, halogen atom, methyl, ethyl, isopropyl, amino, hydroxyl, carboxyl, sulfo group, nitro etc. can be enumerated.

Wherein, from the view point of storage stability and passivation effect, R ¹be preferably the unsubstituted alkyl of carbon number 1 ~ 8, be more preferably the unsubstituted alkyl of carbon number 1 ~ 4.

In general formula (I), m represents the integer of 0 ~ 5.From the view point of storage stability, m is preferably the integer of 1 ~ 5.

For the compound shown in general formula (I), from the view point of passivation effect, M preferably comprises at least a kind of metallic element be selected from Nb, Ta and Y.In addition, from the view point of making the fixed charge density of passivation layer be negative, M preferably comprises at least a kind of metallic element be selected from Nb, Ta, V and Hf, is more preferably at least a kind of being selected from Nb, Ta, VO and Hf.

In addition, as the compound shown in general formula (I), from the view point of storage stability and passivation effect, R ¹be more preferably the unsubstituted alkyl of carbon number 1 ~ 4, from the view point of storage stability, m is preferably the integer of 1 ~ 5.

The state of the compound shown in general formula (I) both can be solid, also can be liquid.From the storage stability of passivation layer formation composition and and by blended viewpoint during compound general formula described later (II) Suo Shi, the compound shown in general formula (I) preferably at normal temperature (25 DEG C) in liquid.

Compound shown in general formula (I) can enumerate niobium, methyl alcohol niobium, ethanol niobium, isopropyl alcohol niobium, normal propyl alcohol niobium, n-butanol niobium, tert-butyl alcohol niobium, isobutanol niobium, methyl alcohol tantalum, ethanol tantalum, tantalum, isopropyl alcohol tantalum, normal propyl alcohol tantalum, n-butanol tantalum, tert-butyl alcohol tantalum, isobutanol tantalum, yttrium, methyl alcohol yttrium, ethanol yttrium, yttrium isopropoxide, normal propyl alcohol yttrium, n-butanol yttrium, tert-butyl alcohol yttrium, isobutanol yttrium, vanadium, methoxyl group vanadium oxide, ethyoxyl vanadium oxide, isopropoxy vanadium oxide, positive propoxy vanadium oxide, n-butoxy vanadium oxide, tert-butoxy vanadium oxide, isobutoxy vanadium oxide, hafnium, methyl alcohol hafnium, ethanol hafnium, isopropyl alcohol hafnium, normal propyl alcohol hafnium, n-butanol hafnium, tert-butyl alcohol hafnium, isobutanol hafnium etc., wherein, preferred alcohol niobium, normal propyl alcohol niobium, n-butanol niobium, ethanol tantalum, normal propyl alcohol tantalum, n-butanol tantalum, yttrium isopropoxide and n-butanol yttrium.From the view point of obtaining negative fixed charge density, preferred alcohol niobium, normal propyl alcohol niobium, n-butanol niobium, ethanol tantalum, normal propyl alcohol tantalum, n-butanol tantalum, ethyoxyl vanadium oxide, positive propoxy vanadium oxide, n-butoxy vanadium oxide, ethanol hafnium, normal propyl alcohol hafnium and n-butanol hafnium.

In addition, the compound shown in general formula (I) both can use the compound prepared, and also can use commercially available product.As commercially available product, include, for example: five methyl alcohol niobiums of high-purity chemical research institute of Co., Ltd., five ethanol niobiums, five isopropyl alcohol niobiums, five normal propyl alcohol niobiums, five isobutanol niobiums, five n-butanol niobiums, five sec-butyl alcohol niobiums, five methyl alcohol tantalums, five ethanol tantalums, five isopropyl alcohol tantalums, five normal propyl alcohol tantalums, five isopropyl alcohol tantalums, five n-butanol tantalums, five sec-butyl alcohol tantalums, five tert-butyl alcohol tantalums, trimethoxy vanadium oxide (V), triethoxy vanadium oxide (V), three isopropoxy vanadium oxides (V), three positive propoxy vanadium oxides (V), three isobutoxy vanadium oxides (V), three n-butoxy vanadium oxides (V), three sec-butoxy vanadium oxides (V), three tert-butoxy vanadium oxides (V), three yttrium isopropoxides, three n-butanol yttriums, four methyl alcohol hafniums, tetraethoxide hafnium, four isopropyl alcohol hafniums, four tert-butyl alcohol hafniums, the five ethanol niobiums of Hokko Chemical Industry Co., Ltd., five ethanol tantalums, five butanols tantalums, n-butanol yttrium, tert-butyl alcohol hafnium, the triethoxy vanadium oxide, three positive propoxy vanadium oxides, three n-butoxy vanadium oxides, three isobutoxy vanadium oxides, three sec-butoxy vanadium oxides etc. of Nichia Chemical Industries, Ltd.

In preparation formula (I) compound (m is the situation of 1 ~ 5) situation, as its preparation method, the halide of contained specific metallic element (M) and alcohol can be used in formula (I) compound to react in the presence of an inert organic solvent and adds the known method for making such as the method (Japanese Laid-Open Patent Publication 63-227593 publication and Japanese Unexamined Patent Publication 3-291247 publication etc.) of ammonia or amines in order to slough halogen.

The containing ratio of formula (I) compound contained in passivation layer formation composition can suitably be selected as required.From the view point of storage stability and passivation effect, the containing ratio of formula (I) compound can be set to 0.1 quality % ~ 80 quality % in passivation layer formation composition, be preferably 0.5 quality % ~ 70 quality %, be more preferably 1 quality % ~ 60 quality %, more preferably 1 quality % ~ 50 quality %.

When passivation layer formation composition contains the compound (below also referred to as special metal alkoxide compound) of m=1 ~ 5 in formula (I) compound, chelating reagent (chelating agent) can be added in above-mentioned metal alkoxides salt compound.As chelating reagent, can exemplify: the omega-dicarboxylic acids such as EDTA (ethylenediamine tetra-acetic acid), bipyridine, ferroheme (heme), naphthyridines, benzimidazolyl methylamine, oxalic acid, malonic acid, butanedioic acid, glutaric acid, adipic acid, tartaric acid, maleic acid, fumaric acid; Beta-diketone compound; Beta-diketonate compound; And diester malonate.

As chelating reagent, specifically, can illustrate: acetylacetone,2,4-pentanedione, 3-methyl-2,4-pentanedione, 2,3-pentanediones, 3-ethyl-2,4-pentanedione, 3-butyl-2,4-pentanedione, 2,2,6,6-tetramethyl-3,5-heptadione, 2, the beta-diketone compounds such as 6-dimethyl-3,5-heptadione, 6-methyl-2,4-heptadione, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, isobutyl acetoacetate, butyl-acetoacetate, tert-butyl acetoacetate, acetoacetate pentyl ester, isoamyl acetoacetate, the own ester of acetoacetate, acetoacetate n-octyl, acetoacetate heptyl ester, acetoacetate 3-pentyl ester, 2-acetyl cognac oil, 2-butyl ethylacetoacetate, 4, 4-dimethyl-3-oxopentanoic acid methyl ester, 4-methyl-3-oxopentanoic acid methyl ester, 2-ethyl acetoacetic ester, hexyl ethyl acetoacetate, 4-methyl-3-oxopentanoic, isopropyl acetoacetate, 3-oxo ethyl hexanoate, 3-oxopentanoic acid methyl ester, 3-oxopentanoic, 3-oxo methyl caproate, 2-methyl-acetoacetic ester, 3-oxoheptanoate, 3-oxo-heptanoic acid methyl esters, 4, the beta-diketonate compounds such as 4-dimethyl-3-oxopentanoic, the diester malonates such as dimethyl malenate, diethyl malonate, dipropyl malonate, Diisopropyl malonate, dibutyl malonate, malonic acid di tert butyl carbonate, malonic acid dihexyl, malonic acid t-butyl acetate, methyl-malonic ester, ethyl malonic acid diethylester, diethyl isopropyl, diethyl butylmalonate, s-Butylmalonic acid diethylester, iso-butyl diethyl malonate, 1-methyl butyl diethyl malonate.

When special metal alkoxide compound has chelate structure, the existence of above-mentioned chelate structure can utilize the analytical method usually used to confirm.Infrared spectroscopy spectrum, NMR spectrum or fusing point etc. such as can be used to confirm.

Special metal alkoxide compound also can use under the state through hydrolysis and dehydrating polycondensation.In order to be hydrolyzed and dehydrating polycondensation, can react under the state that there is water and catalyst, also can by water and catalyst distillation removing after hydrolysis and dehydrating polycondensation.As catalyst, can illustrate: the inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, boric acid, phosphoric acid, hydrofluoric acid; And the organic acid such as formic acid, acetic acid, propionic acid, butyric acid, oleic acid, linoleic acid, salicylic acid, benzoic acid, fumaric acid, oxalic acid, lactic acid, butanedioic acid.In addition, as catalyst, the alkali such as ammonia, amine can be added.

Passivation layer formation composition can contain other precursor of the special metal oxide except formula (I) compound.As long as other precursor of special metal oxide can utilize heat treatment (burning till) and become the material of special metal oxide, then there is no particular restriction.Specifically, as other precursor of special metal oxide, can illustrate: niobic acid, niobium chloride, columbium monoxide, niobium carbide, niobium hydroxide, tantalic acid, tantalic chloride, tantalum pentabromide, vanadium oxydichloride, vanadium trioxide, oxo two (2,4-pentanedione) close vanadium, yttrium chloride, yttrium nitrate, yttrium oxalate, yttrium stearate, yttrium carbonate, aphthenic acids yttrium, propionic acid yttrium, yttrium nitrate, sad yttrium, hafnium chloride, four (2,4-pentanediones) close hafnium etc.

Passivation layer formation composition can also comprise at least a kind (below also referred to as other inorganic compound) in other inorganic oxide and precursor thereof be selected from except special metal compound.As other inorganic compound, aluminium oxide, silica, titanium oxide, gallium oxide, zirconia, boron oxide, indium oxide, phosphorous oxide, zinc oxide, lanthana, praseodymium oxide, neodymia, promethium oxide, samarium oxide, europium oxide, gadolinium oxide, terbium oxide, dysprosia, holimium oxide, erbium oxide, thulium oxide, ytterbium oxide, luteium oxide and their precursor can be enumerated.From the view point of the height of passivation effect and through time deterioration suppression, as other inorganic compound, preferably be selected from least a kind in silica, titanium oxide, zirconia, neodymia, aluminium oxide and their precursor, from the view point of improving passivation effect further, more preferably containing at least a kind that is selected from aluminium oxide and precursor thereof.As the precursor of aluminium oxide, the compound shown in preferred following general formula (II).

[changing 3]

In formula (II), R ²separately represent the alkyl of carbon number 1 ~ 8.N represents the integer of 0 ~ 3.X ²and X ³separately represent oxygen atom or methylene.R ³, R ⁴and R ⁵separately represent the alkyl of hydrogen atom or carbon number 1 ~ 8.At this, work as R ²~ R ⁵, X ²and X ³in any one when existing multiple, existing multiple group represented with prosign can be identical or different respectively.

From the view point of improving passivation effect further, preferably containing being selected from Al ₂o ₃and at least a kind of aluminium compound in the compound (below also referred to as organo-aluminum compound) shown in following general formula (II).

In general formula (II), R ²separately represent the alkyl of carbon number 1 ~ 8, be preferably the alkyl of carbon number 1 ~ 4.R ²shown alkyl both can be straight-chain, also can be branched.As R ²shown alkyl, specifically, can enumerate methyl, ethyl, propyl group, isopropyl, butyl, isobutyl group, sec-butyl, the tert-butyl group, hexyl, octyl group, 2-ethylhexyl etc.Wherein, from the view point of storage stability and passivation effect, R ²shown alkyl is preferably the unsubstituted alkyl of carbon number 1 ~ 8, is more preferably the unsubstituted alkyl of carbon number 1 ~ 4.

In general formula (II), n represents the integer of 0 ~ 3.From the view point of storage stability, n is preferably the integer of 1 ~ 3, is more preferably 1 or 3.In addition, X ²and X ³separately represent oxygen atom or methylene.From the view point of storage stability, X ²and X ³in at least one party be preferably oxygen atom.

R in general formula (II) ³, R ⁴and R ⁵separately represent the alkyl of hydrogen atom or carbon number 1 ~ 8.R ³, R ⁴and R ⁵shown alkyl both can be straight-chain, also can be branched.R ³, R ⁴and R ⁵shown alkyl can have substituting group, also can be unsubstituted alkyl, is preferably unsubstituted alkyl.As R ³, R ⁴and R ⁵shown alkyl is the alkyl of carbon number 1 ~ 8, is preferably the alkyl of carbon number 1 ~ 4.As R ³, R ⁴and R ⁵shown alkyl, specifically, can enumerate methyl, ethyl, propyl group, isopropyl, butyl, isobutyl group, sec-butyl, the tert-butyl group, hexyl, octyl group, 2-ethylhexyl etc.

Wherein, from the view point of storage stability and passivation effect, preferably make the R in general formula (II) ³and R ⁴be separately the unsubstituted alkyl of hydrogen atom or carbon number 1 ~ 8, be more preferably the unsubstituted alkyl of hydrogen atom or carbon number 1 ~ 4.

In addition, from the view point of storage stability and passivation effect, the R in general formula (II) ⁵be preferably the unsubstituted alkyl of hydrogen atom or carbon number 1 ~ 8, be more preferably the unsubstituted alkyl of hydrogen atom or carbon number 1 ~ 4.

From the view point of storage stability, the compound shown in general formula (II) preferably n be 1 ~ 3 integer and R ⁵it is separately the compound of the alkyl of hydrogen atom or carbon number 1 ~ 4.

From the view point of storage stability and passivation effect, the compound shown in general formula (II) is preferably selected from n and is 0 and R ²separately for the compound of alkyl of carbon number 1 ~ 4 and n be 1 ~ 3, R ²be separately alkyl, the X of carbon number 1 ~ 4 ²and X ³in at least one party be oxygen atom, R ³and R ⁴separately alkyl, the R of hydrogen atom or carbon number 1 ~ 4 ⁵for at least a kind in the compound of the alkyl of hydrogen atom or carbon number 1 ~ 4.

Compound shown in general formula (II) is more preferably selected from n and is 0 and R ²for the compound of the unsubstituted alkyl of carbon number 1 ~ 4 and n be 1 ~ 3, R ²for unsubstituted alkyl, the X of carbon number 1 ~ 4 ²and X ³in at least one party be oxygen atom, R that above-mentioned oxygen atom combines ³or R ⁴for carbon number 1 ~ 4 alkyl and at X ²or X ³for the R that methylene above-mentioned during methylene combines ³or R ⁴for hydrogen atom, R ⁵for at least a kind in the compound of hydrogen atom.

As shown in general formula (II), n be 0 organo-aluminum compound (three aluminium alkoxides), specifically, three aluminium methoxides, three aluminium ethylates, aluminum isopropylate, three (2-butanols) aluminium, list (2-butoxy) aluminum-diisopropoxide, three tert-butyl alcohol aluminium, three Tributyl aluminates etc. can be enumerated.

In addition, as shown in general formula (II), n is the organo-aluminum compound of 1 ~ 3, specifically, oacetic acid aluminum-diisopropoxide ((oacetic acid) aluminum-diisopropoxide), three (oacetic acid) aluminium etc. can be enumerated.

Shown in general formula (II), n be 1 ~ 3 organo-aluminum compound both can use the compound prepared, also can use commercially available product.As commercially available product, include, for example trade name and ALCH, ALCH-50F, ALCH-75, ALCH-TR, ALCH-TR-20 etc. of Kawaken FineChemicals Co., Ltd..

Organo-aluminum compound is preferably the aluminium chelate compound of n=1 ~ 3 in formula (II).Aluminium chelate compound also has aluminium chelate structure except the aluminium alkoxide structure of n=0.

When contain the aluminium alkoxide of the n=0 in formula (II) in passivation layer formation composition, preferably make in passivation layer formation composition containing chelating reagent (chelating agent).As chelating reagent, above-mentioned chelating reagent can be enumerated, be preferably the compound that beta-diketone compound, beta-diketonate compound, diester malonate etc. have the ad hoc structure of 2 carbonyls.

Alkoxide structure in organo-aluminum compound and the existence of chelate structure can utilize the analytical method usually used to confirm.Infrared spectroscopy spectrum, NMR spectrum, fusing point etc. such as can be used to confirm.

Think: by also using aluminium alkoxide and chelating reagent or using through sequestration organo-aluminum compound, thus improve thermal stability and the chemical stability of organo-aluminum compound, and the transformation to aluminium oxide when making heat treatment is inhibited.Result is thought: the transformation of the aluminium oxide of the crystalline state of thermotropism mechanics quality stable is suppressed, and easily forms the aluminium oxide of amorphous state.

In addition, the state of the metal oxide in the passivation layer formed can confirm by measuring X-ray diffraction spectrogram (XRD, X-ray diffraction).Such as, impalpable structure can be confirmed as because XRD does not show specific reflection graphic patterns.When passivation layer formation composition includes machine aluminium compound, it to be heat-treated and aluminium oxide in the passivation layer obtained is preferably impalpable structure.If aluminium oxide is amorphous state, then easily produces aluminium defect or oxygen defect, easily produce fixed charge in the passivation layer, and easily obtain larger passivation effect.

Shown in general formula (II), n be 1 ~ 3 organo-aluminum compound can by being prepared by three aluminium alkoxides of 0 and the compound of the ad hoc structure with 2 carbonyls by n.As the compound of ad hoc structure with 2 carbonyls, above-mentioned chelating reagent can be enumerated.In addition, commercially available aluminium chelate compound can also be used.When by above-mentioned three aluminium alkoxides and chelating reagent mixing, the occurring to replace with the compound of ad hoc structure at least partially and form aluminium chelate structure of the silane alcohol base of three aluminium alkoxides.Now can there is solvent as required, in addition, also can carry out the interpolation of heat treated or catalyst.Aluminium chelate structure is replaced at least partially by what make aluminium alkoxide structure, thus organo-aluminum compound is improved for the stability of hydrolysis and polymerization reaction, and the storage stability of the passivation layer formation composition comprising this organo-aluminum compound is improved further.

When organo-aluminum compound has aluminium chelate structure, as long as the number of aluminium chelate structure is 1 ~ 3, then there is no particular restriction.Wherein, from the view point of storage stability, be preferably 1 or 3, be more preferably 1.The number of aluminium chelate structure such as can by suitably adjusting above-mentioned three aluminium alkoxides and the above-mentioned blending ratio with the compound of the ad hoc structure of 2 carbonyls controls.In addition, also from commercially available aluminium chelate compound, suitably the compound with desired structure can be selected.

In the organo-aluminum compound shown in general formula (II), from the view point of passivation effect and the intermiscibility with the solvent added as required, specifically, preferred use is selected from least one in oacetic acid aluminum-diisopropoxide and aluminum isopropylate, more preferably uses oacetic acid aluminum-diisopropoxide.

Organo-aluminum compound both can be aqueous, and can be also solid, there is no particular restriction.From the view point of passivation effect and storage stability, be used in the organo-aluminum compound of stability under normal temperature (25 DEG C) and dissolubility or favorable dispersibility, thus the homogenieity of formed passivation layer is improved further, and can stably obtain required passivation effect.

Comprise at above-mentioned passivation layer formation composition and be selected from Al ₂o ₃and when at least a kind of aluminium compound in the compound shown in above-mentioned general formula (II), the containing ratio of above-mentioned aluminium compound is preferably 0.1 quality % ~ 80 quality %, is more preferably 10 quality % ~ 70 quality %.From the view point of improving passivation effect further, above-mentioned aluminium compound is relative to the compound shown in special metal compound, above-mentioned general formula (II) and Al ₂o ₃the containing ratio of total amount be preferably 0.1 quality % ~ 99.9 quality %, be more preferably 1 quality % ~ 99 quality %, more preferably 2 ~ 70 quality %.

When passivation layer formation composition contains aluminium compound, the composition of the metal oxide in the passivation layer obtained as heat-treating passivation layer formation composition, can enumerate: Nb ₂o ₅-Al ₂o ₃, Al ₂o ₃-Ta ₂o ₅, Al ₂o ₃-Y ₂o ₃, Al ₂o ₃-V ₂o ₅, Al ₂o ₃-HfO ₂etc. binary system composite oxides; And Nb ₂o ₅-Al ₂o ₃-Ta ₂o ₅, Al ₂o ₃-Y ₂o ₃-Ta ₂o ₅, Nb ₂o ₅-Al ₂o ₃-V ₂o ₅, Al ₂o ₃-HfO ₂-Ta ₂o ₅etc. ternary system composite oxides.

Passivation layer formation composition is preferably containing being selected from Nb ₂o ₅and the M in above-mentioned general formula (I) is at least one niobium compound in the compound of Nb.When passivation layer formation composition contains above-mentioned niobium compound, the containing ratio of the above-mentioned niobium compound in passivation layer formation composition is with Nb ₂o ₅convert and be preferably 0.1 quality % ~ 99.9 quality %, be more preferably 1 quality % ~ 99 quality %, more preferably 30 quality % ~ 85 quality %.

When passivation layer formation composition contains niobium compound, the composition of the metal oxide in the passivation layer obtained as heat-treating passivation layer formation composition, can enumerate: Nb ₂o ₅-Al ₂o ₃, Nb ₂o ₅-Ta ₂o ₅, Nb ₂o ₅-Y ₂o ₃, Nb ₂o ₅-V ₂o ₅, Nb ₂o ₅-HfO ₂etc. binary system composite oxides; And Nb ₂o ₅-Al ₂o ₃-Ta ₂o ₅, Nb ₂o ₅-Y ₂o ₃-Ta ₂o ₅, Nb ₂o ₅-Al ₂o ₃-V ₂o ₅, Nb ₂o ₅-HfO ₂-Ta ₂o ₅etc. ternary system composite oxides.

Give above-mentioned passivation layer formation composition to semiconductor substrate and form the composition layer of required form, and (burning till) is heat-treated to combinations thereof nitride layer, the passivation layer with excellent passivation effect can be formed thus.In addition, above-mentioned passivation layer formation composition can suppress the generation of the unfavorable conditions such as gelation and make excellent storage stability by the time.

(liquid medium)

Above-mentioned passivation layer formation composition preferably comprises liquid medium (solvent or decentralized medium).By making passivation layer formation composition contain liquid medium, thus more easily adjust viscosity, imparting is improved further and uniform thermal treatment layer can be formed.As long as above-mentioned liquid medium can dissolve or disperse special metal compound, then there is no particular restriction, can suitably select as required.Liquid medium refers to the medium in liquid condition under room temperature (25 DEG C).

As liquid medium, specifically, can enumerate: the ketone solvents such as acetone, methylethylketone, methyl n-pro-pyl ketone, methyl isopropyl Ketone, methyl n-butyl ketone, methyl iso-butyl ketone (MIBK), methyl-n-amyl ketone, methyl n hexyl ketone, metacetone, dipropyl ketone, DIBK, trimethyl nonanone, cyclohexanone, cyclopentanone, methyl cyclohexanone, 2,4-pentanediones, acetonyl acetone, Anaesthetie Ether, methyl ethyl ether, methyl n-propyl ether, Di Iso Propyl Ether, oxolane, methyltetrahydrofuran, diox, dimethyl dioxane, ethylene glycol dimethyl ether, ethylene glycol bisthioglycolate ethylether, ethylene glycol bisthioglycolate n-propyl ether, ethylene glycol bisthioglycolate butyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol methyl n-propyl ether, diethylene glycol methyl n-butyl ether, diethylene glycol diη-propyl ether, diethylene glycol di-n-butyl ether, diethylene glycol diola, triethylene glycol dimethyl ether, triethylene glycol Anaesthetie Ether, triethylene glycol methyl ethyl ether, triethylene glycol methyl n-butyl ether, triethylene glycol di-n-butyl ether, triethylene glycol diola, TEG dimethyl ether, TEG Anaesthetie Ether, TEG methyl ethyl ether, TEG methyl n-butyl ether, TEG di-n-butyl ether, TEG diola, TEG di-n-butyl ether, propylene glycol dimethyl ether, propylene glycol Anaesthetie Ether, propylene glycol diη-propyl ether, propylene glycol dibutyl ethers, DPG dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol methyl ethylether, dipropylene glycol methyl n-butyl ether, DPG diη-propyl ether, DPG di-n-butyl ether, dipropylene glycol methyl n-hexyl ether, tripropylene glycol dimethyl, tripropylene glycol Anaesthetie Ether, tripropylene glycol methyl ethyl ether, tripropylene glycol methyl n-butyl ether, tripropylene glycol di-n-butyl ether, tripropylene glycol diola, four propylene glycol dimethyl ether, four propylene glycol Anaesthetie Ethers, four propylene glycol methyl ethyl ethers, four propylene glycol methyl n-butyl ether, four propylene glycol di-n-butyl ethers, four propylene glycol methyl n-hexyl ethers, the ether solvents such as four propylene glycol di-n-butyl ethers, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, n-amyl acetate, sec-amyl acetate, acetic acid 3-methoxybutyl, methyl amyl acetate, acetic acid 2-ethyl butyl ester, acetic acid 2-Octyl Nitrite, acetic acid 2-(2-Butoxyethoxy) ethyl ester, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, nonyl acetate, methyl acetoacetate, ethyl acetoacetate, acetic acid diethylene ester, acetic acid TC ester, acetic acid dipropylene glycol methyl ether ester, acetic acid dipropylene glycol ethyl ether ester, diacetate glycol ester, acetic acid methoxy triethylene ester, isoamyl acetate, ethyl propionate, n-butyl propionate, isoamyl propionate, diethy-aceto oxalate, dibutyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, N_amyl lactate, Ethylene Glycol Methyl ether propionic ester, glycol ethyl ether propionic ester, Ethylene Glycol Methyl ether acetic acid ester, ethylene glycol monoethyl ether acetate, methyl proxitol acetate, propylene glycol ethyl ether acetic acid esters, propylene glycol propyl ether acetic acid esters, gamma-butyrolacton, the ester solvents such as gamma-valerolactone, acetonitrile, 1-METHYLPYRROLIDONE, N-ethyl pyrrolidone, N-propyl pyrrole alkane ketone, N-butyl pyrrolidine ketone, N-hexyl pyrrolidones, N-cyclohexyl pyrrolidone, N, the aprotic polar solvent such as dinethylformamide, DMA, dimethyl sulfoxide (DMSO), the hydrophobic organic solvents such as carrene, chloroform, dichloroethanes, benzene,toluene,xylene, hexane, octane, ethylo benzene, 2 ethyl hexanoic acid, methyl iso-butyl ketone (MIBK), methylethylketone, methyl alcohol, ethanol, normal propyl alcohol, isopropyl alcohol, n-butanol, isobutanol, sec-butyl alcohol, the tert-butyl alcohol, n-amyl alcohol, isoamyl alcohol, 2-methyl butanol, sec-amyl alcohol, tert-pentyl alcohol, 3-methoxybutanol, n-hexyl alcohol, 2-methyl anyl alcohol, secondary hexyl alcohol, 2-ethyl butanol, secondary enanthol, n-octyl alcohol, 2-Ethylhexyl Alcohol, sec-octyl alcohol, n-nonyl alcohol, Decanol, secondary tip-nip, Exxal 12, secondary tetradecanol, secondary heptadecanol, cyclohexanol, methyl cyclohexanol, isobornyl cyclohexanol, benzylalcohol, ethylene glycol, 1, 2-propylene glycol, 1, 3-butanediol, diethylene glycol, DPG, triethylene glycol, the alcoholic solvents such as tripropylene glycol, the glycol monoethers solvents such as ethylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol list phenyl ether, diethylene glycol monomethyl ether, TC, diethylene glycol list n-butyl ether, diethylene glycol list n-hexyl ether, ethoxytriglycol, TEG list n-butyl ether, propylene glycol monomethyl ether, DPGME, dihydroxypropane single-ethyl ether, tripropylene glycol monomethyl ether, the terpene solvents such as terpinenes, terpineol, laurene, alloocimene, citrene, cinene, firpene, carvol, ocimenum, phellandrene, water etc.These liquid mediums can be used alone a kind or combinationally use two or more.

Wherein, from the view point of to the imparting of semiconductor substrate and patternability, above-mentioned liquid medium preferably comprises at least a kind that is selected from hydrophobic organic solvent, non-proton organic solvent, terpene solvent, ester solvent, ether solvents and alcoholic solvent, more preferably comprise at least a kind that is selected from terpene solvent, ester solvent and alcoholic solvent, preferably comprise at least a kind that is selected from terpene solvent further.

When passivation layer formation composition contains liquid medium, the containing ratio of the liquid medium in passivation layer formation composition can consider imparting property, patternability, storage stability decide.Such as, from the view point of imparting and the patternability of passivation layer formation composition, the containing ratio of liquid medium is preferably 5 quality % ~ 98 quality % in the gross mass of passivation layer formation composition, is more preferably 10 quality % ~ 95 quality %.

(resin)

Above-mentioned passivation layer formation composition preferably comprises at least a kind of resin.By comprising resin, thus the shape stability of the composition layer making to give above-mentioned passivation layer formation composition on a semiconductor substrate and formed improves further, optionally can form passivation layer in the region being formed with combinations thereof nitride layer according to required form.

There is no particular restriction for the kind of resin.Wherein, the resin that viscosity can be adjusted to the scope that can form good pattern when giving passivation layer formation composition is on a semiconductor substrate preferably.As resin, specifically, can enumerate: polyvinyl alcohol, polyacrylamide, polyacrylamide derivative, polyvinyl lactam, polyvinyl lactam derivative, PVP, poly(ethylene oxide), polyethylene oxide derivant, poly-sulfonic acid, acrylamide alkyl sulfonic acid, cellulose, cellulose derivative (carboxymethyl cellulose, hydroxyethylcellulose, the cellulose ether etc. of ethyl cellulose etc.), gelatin, gelatine derivative, starch, starch derivatives, sodium alginate, sodium alginate derivative, xanthans, xanthan derivatives, guar gum, guar derivative, scleroglucan, scleroglucan derivative, bassora gum, bassora gum derivative, dextrin, dextrin derivative, (methyl) acrylic resin, (methyl) acrylate ((methyl) acid alkyl ester resin, (methyl) dimethylaminoethyl acrylate resin etc.), butadiene resin, styrene resin, silicone resin, the copolymer etc. of these resins.These resins can be used alone a kind or combinationally use two or more.

In addition, " (methyl) acrylic acid " in this specification refers at least one party in " acrylic acid " and " methacrylic acid ", and " (methyl) acrylate " refers at least one party in " acrylate " and " methacrylate ".

In these resins, from the view point of storage stability and patternability, preferred use does not have the resinene of the functional group of acidity and alkalescence, even if adjusting viscosity and thixotropic viewpoint also can be easy to from when content is few, more preferably use the cellulose derivative of ethyl cellulose etc.

There is no particular restriction for the molecular weight of resin, preferably in view of viscosity needed for passivation layer formation composition suitably adjusts.From the view point of storage stability and patternability, the weight average molecular weight of resin is preferably 100 ~ 10, and 000,000, be more preferably 1,000 ~ 5,000,000.In addition, the weight average molecular weight of resin is undertaken converting by the molecular weight distribution using GPC (gel permeation chromatography) to record by using the calibration curve of polystyrene standard and obtains.Calibration curve uses 5 sample sets of polystyrene standard (PStQuick MP-H, PStQuick B [eastern Cao (strain) system, trade name]) to be similar to gained with 3 formulas.The condition determination of GPC is below shown.

Device: (pump: L-2130 type [new and high technology Co., Ltd. of Hitachi])

(detector: L-2490 type RI [new and high technology Co., Ltd. of Hitachi])

(column oven: L-2350 [new and high technology Co., Ltd. of Hitachi])

Chromatographic column: Gelpack GL-R440+Gelpack GL-R450+Gelpack GL-R400M (amounting to 3) (Hitachi Chemical Co., Ltd., trade name)

Column size: 10.7mm (internal diameter) × 300mm

Eluent: oxolane

Sample solution concentration: 10mg/2mL

Injection rate: 200 μ L

Flow: 2.05mL/ minute

Measure temperature: 25 DEG C

When passivation layer formation composition contains resin, the containing ratio of the resin in passivation layer formation composition can suitably be selected as required.The containing ratio of such as resin is preferably 0.1 quality % ~ 30 quality % in passivation layer formation composition.From the thixotropic viewpoint embodied as more easily formed pattern and so on, the containing ratio of resin is more preferably 1 quality % ~ 25 quality %, more preferably 1.5 quality % ~ 20 quality %, is particularly preferably 1.5 quality % ~ 10 quality %.

When above-mentioned passivation layer formation composition contains resin, can suitably selecting as required containing ratio of special metal compound and resin.Wherein, from the view point of patternability and storage stability, resin-phase for special metal compound total amount be preferably 0.001 ~ 1000 containing ratio (resin/special metal compound), be more preferably 0.01 ~ 100, more preferably 0.1 ~ 1.

Above-mentioned passivation layer formation composition can contain acid compound or alkali compounds.When passivation layer formation composition contains acid compound or alkali compounds, from the view point of storage stability, preferably make the containing ratio of the acid compound in passivation layer formation composition or alkali compounds be respectively below 1 quality %, be more preferably below 0.1 quality %.

As acid compound, Bronsted acid (bronsted acid) and lewis acid can be enumerated.Specifically, can enumerate: the inorganic acid such as hydrochloric acid, nitric acid; The organic acids etc. such as acetic acid.In addition, as alkali compounds, brnsted base and lewis base can be enumerated.Specifically, can enumerate: the inorganic base such as alkali metal hydroxide, alkaline earth metal hydroxide; The organic base such as trialkylamine, pyridine etc.

Above-mentioned passivation layer formation composition can contain the various additives such as tackifier, wetting agent, surfactant, inorganic particulate, the resin comprising silicon atom, thixotropic agent as required as other composition.

As inorganic particulate, silicon dioxide (silica), clay, carborundum, silicon nitride, montmorillonite, bentonite, carbon black etc. can be illustrated.Wherein, preferably use comprises the filler of silicon dioxide as composition.At this, clay represents layered clay mineral, specifically, kaolin, thread allophane (Imogolite), montmorillonite, montmorillonite (Smectite), sericite, mullite (illite), talcum, humite (stevensite), zeolite etc. can be enumerated.When passivation layer formation composition contains inorganic particulate, there is the tendency of the imparting improving passivation layer formation composition.

As surfactant, non-ionic surface active agent, cationic surfactant, anion surfactant etc. can be enumerated.Wherein, from aspect, preferred nonionic surfactants or cationic surfactant that the impurity such as the heavy metal brought in semiconductor device are few.And then, as non-ionic surface active agent, silicon surface active agent, fluorine surfactant and hydrocarbon surfactant etc. can be enumerated.When passivation layer formation composition contains surfactant, the tendency that there is the thickness making to form by above-mentioned passivation layer the composition layer formed with composition and improve the uniformity formed.。

As the resin comprising silicon atom, the alternate copolymer of terminal lysines modified silicone, polyamide and silicone, pendant alkyl group modified silicone, pendant polyether modified silicone, end alkyl modified silicone, silicone modified pulullan polysaccharide (pullulan), silicone modified acrylic resin etc. can be illustrated.The tendency that there is the thickness making to form by passivation layer the composition layer formed with composition and improve the uniformity formed.

As thixotropic agent, polyether compound, fatty acid amide, aerosil, rilanit special, urea urethane acid amides, PVP, oily gelating agent etc. can be illustrated.When above-mentioned passivation layer formation composition contains thixotropic agent, exist improve fine rule formative (give passivation layer is formationed composition time and dry compositions layer time, suppression linear pattern live width thicker) tendency.As polyether compound, polyethylene glycol, polypropylene glycol, poly-(ethylidene-propylidene) diol copolymer etc. can be illustrated.

There is no particular restriction for the viscosity of passivation layer formation composition, suitably can select according to the adding method etc. of semiconductor substrate.Such as, the viscosity of passivation layer formation composition can be set to 0.01Pas ~ 10000Pas.Wherein, from the sight of patternability, the viscosity of passivation layer formation composition is preferably 0.1Pas ~ 1000Pas.In addition, viscosity uses rotary shear viscosity meter at 25 DEG C with shear rate 1.0s ^-1measure.

In addition, there is no particular restriction for the shear viscosity of passivation layer formation composition.Wherein, from the view point of patternability, shear rate 1.0s ^-1time shear viscosity η ₁divided by shear rate 10s ^-1time shear viscosity η ₂and the thixotropic ratio (η calculated ₁/ η ₂) be preferably 1.05 ~ 100, be more preferably 1.1 ~ 50.In addition, shear viscosity uses the rotary shear viscosity meter being provided with cone-plate (diameter 50mm, cone angle 1 °) to measure at temperature 25 DEG C.

There is no particular restriction for the manufacture method of passivation layer formation composition.Normally used method such as can be utilized the mixing such as special metal compound and liquid medium contained as required to be manufactured.In addition, also can by will the liquid medium of resin dissolves and the mixing of special metal compound be made to manufacture.

And then the special metal alkoxide compound of m=1 ~ 5 in formula (I) and the compound that can form chelate with contained special metal element in this special metal alkoxide compound can be prepared by special metal compound.Now, suitably can use liquid medium, also can heat-treat.Passivation layer formation composition can be manufactured by using special metal compound obtained like this.

In addition, contained in the above-mentioned passivation layer formation composition kind of composition and the content of each composition can use the spectrum analyses such as thermal analyses, NMR (nulcear magnetic resonance (NMR)), IR (infrared spectrum), HPLC (high performance liquid chromatography), the analyses of GPC (gel permeation chromatography) isochromatic spectrum etc. such as TG/DTA (differential heat-thermogravimetric amount Simultaneously test) to confirm.

The manufacture method > of < solar cell device

The manufacture method of solar cell device of the present invention has: the operation forming sensitive surface electrode at the sensitive surface of semiconductor substrate; The operation of backplate is formed in the face contrary with above-mentioned sensitive surface of above-mentioned semiconductor substrate and the back side; Passivation layer formation composition is given at least one face in above-mentioned sensitive surface, the above-mentioned back side and side and forms the operation of composition layer, described passivation layer formation composition contains and is selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃, HfO ₂and at least a kind of compound in the compound shown in above-mentioned general formula (I); And combinations thereof nitride layer is heat-treated and forms the operation of passivation layer.The manufacture method of solar cell device of the present invention can have other operation as required further.Passivation layer formation composition can be applied in passivation layer formation composition illustrated in solar cell device.

According to said method, the passivation layer with excellent passivation effect can be formed on a semiconductor substrate.And then above-mentioned passivation layer can be formed by the short-cut method high production rate without the need to evaporation coating device etc.Therefore, according to said method, the solar cell device of conversion efficiency excellence can be manufactured with easy method.

As the method forming sensitive surface electrode and backplate on a semiconductor substrate, the method usually used can be adopted.Such as by giving the electrode formation pastes such as silver-colored paste, Aluminum Paste at the desired zone of semiconductor substrate, and (burning till) can be heat-treated as required formed.

Before the operation forming sensitive surface electrode and the operation forming backplate can form the operation of composition layer at least one face be imparted to by above-mentioned passivation layer formation composition in the sensitive surface of semiconductor substrate, the back side and side, also can after this operation.In addition, can carry out together for the formation of the heat treatment (burning till) of electrode and the heat treatment (burning till) for being formed passivation layer by composition layer, also can carry out with respective independently operation.

In addition, preferably also there is the operation of semiconductor substrate being given to aqueous alkali before the operation forming composition layer.That is, before being imparted on semiconductor substrate by above-mentioned passivation layer formation composition, preferably use the surface of aqueous alkali washing semi-conductor substrate.By washing with aqueous alkali, the organic substance, particulate etc. that are present in semiconductor substrate surface can be removed, and passivation effect is improved further.

As the washing methods utilizing aqueous alkali, known RCA washing etc. can be illustrated usually.Such as, semiconductor substrate be impregnated in the mixed solution of ammoniacal liquor-aquae hydrogenii dioxidi, and process at 60 DEG C ~ 80 DEG C, organic substance and particulate can be removed thus, and can washing semi-conductor substrate.Washing time be preferably 10 second ~ 10 minutes, more preferably 30 second ~ 5 minutes.

Passivation layer formation composition is used at least one face in the sensitive surface of semiconductor substrate, the back side and side and forms the method for composition layer there is no particular restriction.Such as, the method using known adding method etc. to give passivation layer formation composition on a semiconductor substrate can be enumerated.Specifically, the print process such as infusion process, silk screen print method, spin-coating method, spread coating, spray-on process, scraper plate method, rolling method, ink-jet method etc. can be enumerated.Wherein, from the view point of patternability, preferred silk screen print method and ink-jet method, more preferably silk screen print method.

The imparting amount of passivation layer formation composition to semiconductor substrate suitably can be selected according to object.Such as suitably can adjust according to the mode making the thickness of formed passivation layer become aftermentioned desired thickness.

Heat-treat (burning till) with the composition layer that composition is formed to being formed by passivation layer and form the heat treatment nitride layer (burning till nitride layer) deriving from composition layer, thus passivation layer can be formed on a semiconductor substrate.

There is no particular restriction for heat treatment (burning till) condition of composition layer.When passivation layer formation composition contains other metallic compound (organo-aluminum compound etc.) of special metal compound and any composition, as long as the special metal oxide that can change into as its heat treatment thing (burned material) and other inorganic oxide (aluminium oxide (Al ₂o ₃) etc.), then there is no particular restriction for heat treatment (burning till) condition of composition layer.

Wherein, heat treatment (burning till) condition of the special metal oxide of the amorphous without crystalline texture can preferably be formed.By making passivation layer be made up of the special metal oxide of amorphous, thus passivation layer can be made more effectively to hold negative electrical charge, and more excellent passivation effect can be obtained.Specifically, heat treatment (burning till) temperature is preferably more than 400 DEG C, is more preferably 400 DEG C ~ 900 DEG C, more preferably 600 DEG C ~ 800 DEG C.Refer to for the maximum temperature in the stove of heat treatment (burning till) in this said heat treatment (burning till) temperature.Heat treatment (burning till) time suitably can be selected according to heat treatment (burning till) temperature etc.Such as can be set to 5 second ~ 10 hours, be preferably 10 second ~ 5 hours.Retention time is at the maximum temperature referred in this said heat treatment (burning till) time.

In addition, heat treatment (burning till) can by using diffusion furnace (such as ACCURON CQ-1200, International Electric K.K. of Hitachi; 206A-M100, Koyo thermal System Co., Ltd. etc.) etc. carry out.There is no particular restriction to heat-treat the atmosphere of (burning till), can implement in an atmosphere.

In addition, form the operation of passivation layer heat-treating (burning till) to composition layer before can have further the withering operation of composition layer.By having the withering operation of composition layer, can be formed have evenly the passivation layer of passivation effect.

As long as to the removing at least partially of liquid medium that the withering operation of composition layer can will may be included in passivation layer formation composition, then there is no particular restriction.Dry processing example to carry out at 30 DEG C ~ 250 DEG C as being set to 10 second ~ heat treatment of 60 minutes, preferably carry out at 40 DEG C ~ 220 DEG C 30 second ~ heat treatment of 10 minutes.In addition, dry process both can be carried out at ambient pressure, also can under reduced pressure carry out.

With reference to the accompanying drawings embodiments of the present invention are described.

Fig. 1 is the process chart with an example of the manufacture method of the solar cell device of passivation layer schematically showing present embodiment with cutaway view form.But, this process chart to using method of the present invention without any restriction.

As shown in (a) of Fig. 1, form n at the near surface of p-type semiconductor substrate 1 ⁺type diffusion layer 2, and form antireflection film 3 on surface.As antireflection film 3, known silicon nitride film, oxidation titanium film etc.The surface protection film (not shown) of silica etc. can be there is between antireflection film 3 and p-type semiconductor substrate 1.In addition, passivation layer of the present invention also can use as surface protection film.Although now and not shown, also can further stacked antireflection film and become two-layer structure over the passivation layer.When forming passivation layer of the present invention at sensitive surface, even if be not point cantact structure as described later but whole face is formed with the solar battery cell (not shown) of the usual structure of aluminium electrode overleaf, also high conversion efficiency can be realized.

Then, as shown in (b) of Fig. 1, after a part of region coating aluminium electrode paste agent etc. overleaf forms the material of backplate 5, heat-treat (burning till) and form backplate 5, and make in aluminium atoms permeating to p-type semiconductor substrate 1 and form p ⁺type diffusion layer 4.

Then, as shown in (c) of Fig. 1, after electrode formation paste is given in sensitive surface side, heat-treat (burning till) and form sensitive surface electrode 7.By using containing there is the material of the glass particle burning logical (firethrough) property as electrode formation paste, can as shown in (c) of Fig. 1 through antireflection film 3, and at n ⁺type diffusion layer 2 formed sensitive surface electrode 7 and obtain ohmic contact.

Then, as shown in (d) of Fig. 1, utilize silk screen printing etc. in the back side p-type layer except being formed with the region of backplate 5, give passivation layer formation composition and form composition layer.(burning till) is heat-treated to the composition layer be formed in p-type layer and forms passivation layer 6.Form passivation layer 6 by p-type layer overleaf, the solar cell device of generating efficiency excellence can be manufactured.

In the solar cell device utilizing the manufacture method comprising manufacturing process shown in Fig. 1 to manufacture, the backplate formed can be made point cantact structure, and the warpage etc. of substrate can be reduced by aluminium etc.

In addition, the method only partly forming passivation layer has overleaf been shown in (d) of Fig. 1, but also can also give passivation layer formation composition in the side except rear side of p-type semiconductor substrate 1 and it be heat-treated (burning till), thus also form passivation layer 6 (not shown) in the side (edge) of semiconductor substrate 1.Thereby, it is possible to manufacture the more excellent solar cell device of generating efficiency.

In addition, can also passivation layer do not formed overleaf and only give passivation layer formation composition of the present invention in side and (burning till) is heat-treated to it, thus form passivation layer 6.Passivation layer formation composition of the present invention is when the position that the crystal defect such for face, image side is many, and its effect is large especially.

In Fig. 1, the mode forming passivation layer after electrode is formed is illustrated, but also can form the electrode that to utilize after passivation layer evaporation etc. to form aluminium etc. at whole further, in addition, the electrode that can also be formed without the need to heat-treating (burning till) with high temperature at whole.

Fig. 2 is the process chart with another example of the manufacture method of the solar cell device of passivation layer schematically showing present embodiment with cutaway view form.Specifically, Fig. 2 is the process chart comprising following operation with cutaway view formal specification: use aluminium electrode paste agent or heat diffusion treatment can be utilized to form p ⁺the p-diffusion layer formation composition of type diffusion layer forms p ⁺after type diffusion layer, the heat treatment thing of removing aluminium electrode paste agent or p ⁺the heat treatment thing of type diffusion layer formation composition.At this, p-diffusion layer formation composition such as can be formed containing containing recipient element material and glass ingredient.

As shown in (a) of Fig. 2, form n at the near surface of p-type semiconductor substrate 1 ⁺type diffusion layer 2, and form antireflection film 3 on surface.As antireflection film 3, known silicon nitride film, oxidation titanium film etc.

Then, as shown in (b) of Fig. 2, p is given in a part of region overleaf ⁺after type diffusion layer formation composition, heat-treat and form p ⁺type diffusion layer 4.At p ⁺type diffusion layer 4 is formed the heat treatment thing 8 of p-diffusion layer formation composition.

At this, aluminium electrode paste agent can be used to replace p-diffusion layer formation composition.When using aluminium electrode paste agent, at p ⁺type diffusion layer 4 is formed aluminium electrode 8.

Then, as shown in (c) of Fig. 2, the method removings such as etching are utilized to be formed at p ⁺the heat treatment thing 8 of the p-diffusion layer formation composition on type diffusion layer 4 or aluminium electrode 8.

Then, as shown in (d) of Fig. 2, after electrode formation paste is given on a part of regioselectivity ground at sensitive surface (surface) and the back side, heat-treat and form sensitive surface electrode 7 at sensitive surface (surface), and formation backplate 5 overleaf.By use containing have burn the general character the material of glass particle as the electrode formation paste being imparted to sensitive surface side, can as shown in (d) of Fig. 2 through antireflection film 3, and at n ⁺type diffusion layer 2 formed sensitive surface electrode 7 and obtain ohmic contact.

Owing to forming p in the region forming backplate ⁺type diffusion layer 4, the electrode formation paste therefore for the formation of backplate 5 is not limited to aluminium electrode paste agent, and silver electrode paste etc. also can be used can to form the electrode paste of more low-resistance electrode.Thus, also generating efficiency can be improved further.

Then, as shown in (e) of Fig. 2, the back side p-type layer except being formed with the region of backplate 5 gives passivation layer formation composition of the present invention and forms composition layer.Imparting can be undertaken by methods such as silk screen printings.(burning till) is heat-treated to the composition layer be formed in the p-type layer of the back side and forms passivation layer 6.By forming passivation layer 6 in p-type layer, the solar cell device of generating efficiency excellence can be manufactured.

In addition, shown in (e) of Fig. 2, only part forms the method for passivation layer overleaf, but also can also give passivation layer formation composition in the side except rear side of p-type semiconductor substrate 1 and it be heat-treated (burning till), thus also form passivation layer (not shown) in the side (edge) of p-type semiconductor substrate 1.Thereby, it is possible to manufacture the more excellent solar cell device of generating efficiency.

In addition, can also passivation layer do not formed overleaf and only give passivation layer formation composition of the present invention in side and it is heat-treated, thus form passivation layer.Passivation layer formation composition of the present invention is when the position that the crystal defect such for face, image side is many, and its effect is large especially.

In Fig. 2, the mode forming passivation layer after electrode is formed is illustrated, but also can form the electrode that to utilize after passivation layer evaporation etc. to form aluminium etc. at whole further, in addition, the electrode that can also be formed without the need to heat-treating (burning till) with high temperature at whole.

N is formed with in the above-described embodiment to being used in sensitive surface ⁺the situation of the p-type semiconductor substrate of type diffusion layer is illustrated, but is formed with p when being used in sensitive surface ⁺when the n-type semiconductor substrate of type diffusion layer, also similarly can manufacture solar cell device.It should be noted that, now, side forms n overleaf ⁺type diffusion layer.

< solar module >

Solar module of the present invention has above-mentioned solar cell device and is configured at the wiring material on the electrode of above-mentioned solar cell device.Solar module comprises at least 1 above-mentioned solar cell device and on the electrode of solar cell device, configures the wiring materials such as lug line and form.Solar cell can also connect multiple solar cell device by wiring material as required and utilize encapsulant carry out sealing and form.As above-mentioned wiring material and encapsulant, there is no particular restriction, suitably can select from the normally used material of the art.Size for above-mentioned solar module is also unrestricted, is preferably 0.5m ²~ 3m ².

Embodiment

Below, utilize embodiment to further illustrate the present invention, but the present invention is not limited to the examples.

< embodiment 1>

(preparation of passivation layer formation composition)

By Al ₂o ₃film coated material (high-purity chemical research institute of Co., Ltd. " SYM-A104 ", Al ₂o ₃: 2 quality %, dimethylbenzene: 87 quality %, 2-propyl alcohol: 5 quality %, stabilization agent: 6 quality %) 1.0g and Nb ₂o ₅film coated material (high-purity chemical research institute of Co., Ltd. " Nb-05 ", Nb ₂o ₅: 5 quality %, n-butyl acetate: 56 quality %, stabilization agent: 16.5 quality %, viscosity modifier: 22.5 quality %) 1.0g mixing, be prepared into passivation layer formation composition 1.

(formation of passivation layer)

Surface is used to be that the monocrystalline type p-type silicon substrate (square, the thickness of SUMCO Co., Ltd., 50mm: 625 μm) of mirror shape is as semiconductor substrate.RCA cleaning solution (Kanto Kagaku K. K., Frontier Cleaner-A01) is used at 70 DEG C, silicon substrate to be flooded washing 5 minutes, by this has been pre-treatment.

Then, spin coater (three large bamboo hat with a conical crown and broad brim Co., Ltd., MS-100) is used, at 4000rpm (min ^-1), give passivation layer formation composition 1 obtained above to whole of the one side of the silicon substrate through pre-treatment under the condition of 30 seconds.Then, at 150 DEG C, carry out dry process in 3 minutes.Then, with 700 DEG C, its heat treatment in atmosphere (burning till), after 10 minutes, is placed cooling, is made into evaluation substrate under room temperature (25 DEG C).Use horizontal type diffusion furnace (206A-M100, Koyo thermal System Co., Ltd.), to heat-treat (burning till) under maximum temperature 700 DEG C, the condition of 10 minutes retention times under atmosphere in an atmosphere.

(mensuration of useful life)

In determinator in useful life (Japanese Shi Meilebo Co., Ltd., WT-2000PVN), under room temperature (25 DEG C), the useful life (μ s) that is formed with the region of passivation layer of Photoconductivity decay by microwave reflectance damped method to the evaluation substrate of above-mentioned acquisition is utilized to measure.Useful life is 480 μ s.

(mensuration of average thickness)

Use interfere type film thickness gauge (FILMETRICS company, F20 determining film thickness system) to measure the thickness of 5 of passivation layer, and calculate mean value.Average thickness is 82nm.

(mensuration of density)

Density is calculated by the quality of passivation layer and average thickness.Density is 3.2g/cm ³.

(making of solar cell device)

Use utilizes phosphorous oxychloride to form n-type diffusion layer on two sides, and square p-type silicon substrate (Advantec Co., Ltd. of 156mm of SiNx film is formed at one side (sensitive surface side), n-type diffusion layer film resistor: 60 Ω/, complete two sides texture processing, the thickness of SiNx film: 80nm), utilize ink-jet (MICROJET Co., Ltd., ink discharge device " MJP-1500V ", ink gun: IJH-80, jet size: 50 μm × 70 μm) and be coated with passivation layer formation composition 1 according to the region 10 except peristome 9 of the pattern side overleaf of Fig. 3, passivation layer formation composition 1 thickness is after the drying made to reach 5 μm.Afterwards, at 150 DEG C, carry out dry process in 3 minutes.Then, under using horizontal type diffusion furnace (206A-M100, Koyo thermal System Co., Ltd.) atmosphere in an atmosphere and after heat-treating (burning till) under maximum temperature 700 DEG C, the condition of 1 hour retention time, place and be cooled to room temperature (25 DEG C).

Then, side is with the silk screen printing of pattern on the spot aluminium electrode (PVGsolutions Co., Ltd., PVG-AD-02) of 125mm × 125mm overleaf, carries out dry process in 3 minutes at 150 DEG C.Then, the mask to print silk screen printing silver electrode (Dupont Kabushiki Kaisha, PV159A) of pattern shown in Fig. 4 is used in sensitive surface side.Then, at 150 DEG C after drying, use tunnel type firing furnace (NoritakeCo., Ltd.) to heat-treat (burning till) at 700 DEG C, be made into solar cell device.

Solar cell device solar simulator (Solar Simulator) (WACOM ELECTRIC CO., LTD., XS-155S-10) is used to have rated power generation characteristics after 1 hour making solar cell device.The evaluation of power generation performance is by being undertaken the combination of the determinator of simulated solar irradiation (WXS-155S-10, WACOM ELECTRIC CO., LTD.) and voltage-to-current (I-V) evaluating and measuring device (I-V CURVE TRACER MP-180, EKO INSTRUMENT Inc.).Showing as Jsc (short-circuit current density), the Voc (open circuit voltage) of the power generation performance of solar cell, FF (Fill factor), η (conversion efficiency) is the value carried out measuring according to JIS-C-8913 (2005 year) and JIS-C-8914 (2005 year) and obtain respectively.Show the result in table 2.

In addition, the solar cell device be made into is positioned over 50 DEG C, in the constant temperature and humidity cabinet of 80%RH, the power generation characteristics of preservation after 1 month is evaluated.Show the result in table 3.Rate of change (the efficiency eta after preservation of the conversion efficiency after the preservation of solar cell device ²relative to the efficiency eta before preservation ¹[%]) be 99.7%.

[table 1]

Composition (quality %)	Embodiment 1	Embodiment 2	Embodiment 3	Embodiment 4	Embodiment 5
						Al ₂O ₃	1	0	0	0	0
Oacetic acid aluminum-diisopropoxide	0	0	0	0	5
						Nb ₂O ₅	2.5	0	0	0	0
Five ethanol niobiums	0	0	0	0	5
						Ta ₂O ₅	0	10	0	0	0
HfO ₂	0	0	5	0	0
						Y ₂O ₃	0	0	0	3	0
Acetylacetone,2,4-pentanedione	0	0	0	0	10
						N-butyl acetate	28	60	0	22.5	0
Ethyl acetate	0	0	0	8	0
						Isoamyl acetate	0	0	73	0	0
Normal octane	0	9	10	0	0
						2 ethyl hexanoic acid	0	0	0	12.5	0
Dimethylbenzene	43.5	0	0	0	47
						2-propyl alcohol	2.5	0	5	0	3
Terpinol	0	0	0	45	0
						Terpineol	0	0	0	0	30
Stabilization agent	11.25	21	7	0	0
						Viscosity modifier	11.25	0	0	9	0

[table 2]

[table 3]

< embodiment 2>

(preparation of passivation layer formation composition)

Use Ta ₂o ₅film coated material (high-purity chemical research institute of Co., Ltd., " Ta-10-P ", Ta ₂o ₅: 10 quality %, normal octane: 9 quality %, n-butyl acetate: 60 quality %, stabilization agent: 21 quality %) make passivation layer formation composition 2.

Except using above-mentioned obtained passivation layer formation composition 2, make evaluation substrate similarly to Example 1, and evaluate similarly to Example 1.Useful life is 450 μ s.The thickness of passivation layer is 75nm, and density is 3.6g/cm ³.

Using except passivation layer formation composition 2 except replacing passivation layer formation composition 1, making solar cell device similarly to Example 1, and have rated power generation characteristics.

< embodiment 3>

Use HfO ₂film coated material (high-purity chemical research institute of Co., Ltd., " Hf-05 ", HfO ₂content: 5 quality %, isoamyl acetate: 73 quality %, normal octane: 10 quality %, isopropyl alcohol: 5 quality %, stabilization agent: 7 quality %) make passivation layer formation composition 3.

Except using above-mentioned obtained passivation layer formation composition 3, make evaluation substrate similarly to Example 1, and evaluate similarly to Example 1.Useful life is 380 μ s.The thickness of passivation layer is 71nm, and density is 3.2g/cm ³.

Using except passivation layer formation composition 3 except replacing passivation layer formation composition 1, making solar cell device similarly to Example 1, and have rated power generation characteristics.

< embodiment 4>

Use Y ₂o ₃film coated material (high-purity chemical research institute of Co., Ltd., " Y-03 ", Y ₂o ₃: 3 quality %, 2 ethyl hexanoic acid: 12.5 quality %, n-butyl acetate: 22.5 quality %, ethyl acetate: 8 quality %, terpinol: 45 quality %, viscosity modifier: 9 quality %) make passivation layer formation composition 4.

Except using above-mentioned obtained passivation layer formation composition 4, make evaluation substrate similarly to Example 1, and evaluate similarly to Example 1.Useful life is 390 μ s.The thickness of passivation layer is 68nm, and density is 2.8g/cm ³.

Using except passivation layer formation composition 4 except replacing passivation layer formation composition 1, making solar cell device similarly to Example 1, and have rated power generation characteristics.

< embodiment 5>

By oacetic acid aluminum-diisopropoxide (Kawaken Fine Chemicals Co., Ltd., ALCH), five ethanol niobiums (Hokko Chemical Industry Co., Ltd.), acetylacetone,2,4-pentanedione (Wako Pure Chemical Industries, Ltd.), dimethylbenzene (Wako Pure Chemical Industries, Ltd.), 2-propyl alcohol (Wako Pure Chemical Industries, Ltd.) and terpineol (NIPPON TERPENE CHEMICALS, INC.) mix according to the mix proportion shown in table 1, make passivation layer formation composition 5 and use.

Except using above-mentioned obtained passivation layer formation composition 5, on the silicon substrate through pre-treatment, form passivation layer similarly to Example 1, and similarly evaluate.Useful life is 420 μ s.The thickness of passivation layer is 94nm, and density is 2.6g/cm ³.

Using except passivation layer formation composition 5 except replacing passivation layer formation composition 1, making solar cell device similarly to Example 1, and have rated power generation characteristics.

< comparative example 1>

Except not carrying out the imparting of the passivation layer formation composition 1 in embodiment 1, make evaluation substrate and solar cell device similarly to Example 1.The useful life of evaluation of measuring substrate is also evaluated it.Useful life is 20 μ s.

< comparative example 2>

Ethyl cellulose (being evolved into Co., Ltd., ETHOCEL200cps day) 5.0g as resin and terpineol (the Japanese terpene KCC) 95.0g as liquid medium is mixed, stir 1 hour at 150 DEG C, be prepared into ethyl cellulose solution.

By Al ₂o ₃particle (high-purity chemical research institute of Co., Ltd., average grain diameter 1 μm) 2.00g, terpineol 1.98g and ethyl cellulose solution 3.98g mix, and are prepared into water white composition C2.

Except using above-mentioned obtained composition C2, make evaluation substrate similarly to Example 1, and evaluate similarly to Example 1.Useful life is 21 μ s.The thickness of passivation layer is 2.1 μm, and density is 1.4g/cm ³.At this, thickness cannot utilize interfere type film thickness gauge to measure, and therefore utilizes contact pin type jump meter (AmBios company, XP-2) to measure.Specifically, utilize spatula (spatula) to prune the part of substrate, with the condition of speed 0.1mm/s, pin load 0.5mg measure applied part with by the jump of part pruned.Mensuration carries out 3 times, calculates its mean value as thickness.

Using except composition C2 except replacing passivation layer formation composition 1, making solar cell device similarly to Example 1, and have rated power generation characteristics.

< comparative example 3>

Tetraethoxysilane 2.01g, terpineol 1.99g and the ethyl cellulose solution 4.04g that obtains in the same manner as comparative example 2 are mixed, is prepared into water white composition C3.

Except using above-mentioned obtained composition C3, make evaluation substrate similarly to Example 1, and evaluate similarly to Example 1.Useful life is 23 μ s.The thickness of passivation layer is 85nm, and density is 2.1g/cm ³.

Using except composition C3 except replacing passivation layer formation composition 1, making solar cell device similarly to Example 1, and have rated power generation characteristics.

As known from the above, solar cell device of the present invention because possessing the passivation layer with excellent passivation effect and showing high conversion efficiency, and makes the reduction of characteristic of solar cell by the time be inhibited.And then the passivation layer of solar cell device of the present invention can be formed as required form with easy operation.

< reference implementation mode 1>

It is below the silicon substrate of the passivating film of reference implementation mode 1, application type material, solar cell device and band passivating film.

<1> passivating film, it comprises aluminium oxide and niobium oxide, and for having the solar cell device of silicon substrate.

The passivating film of <2> according to <1>, wherein, the mass ratio (niobium oxide/aluminium oxide) of above-mentioned niobium oxide and above-mentioned aluminium oxide is 30/70 ~ 90/10.

The passivating film of <3> according to <1> or <2>, wherein, total containing ratio of above-mentioned niobium oxide and above-mentioned aluminium oxide is more than 90 quality %.

The passivating film of <4> according to any one of <1> ~ <3>, it also comprises organic principle.

The passivating film of <5> according to any one of <1> ~ <4>, it is the heat treatment thing of the application type material comprising alumina precursor and niobium oxide precursor.

<6> application type material, it comprises alumina precursor and niobium oxide precursor, and for the formation of having the passivating film of solar cell device of silicon substrate.

<7> solar cell device, it possesses:

Comprise monocrystalline silicon or polysilicon and there is the p-type silicon substrate at sensitive surface and the back side with above-mentioned sensitive surface opposition side;

Be formed at the N-shaped impurity diffusion layer of the sensitive surface side of above-mentioned silicon substrate;

Be formed at the 1st electrode on the surface of the said n type impurity diffusion layer of the sensitive surface side of above-mentioned silicon substrate;

Be formed at the surface of the rear side of above-mentioned silicon substrate, there is multiple peristome and comprise the passivating film of aluminium oxide and niobium oxide; And

Form with the surface of the rear side of above-mentioned silicon substrate the 2nd electrode be electrically connected by above-mentioned multiple peristome.

<8> solar cell device, it possesses:

Be formed at part or all of the rear side of above-mentioned silicon substrate and be added with the p-type impurity diffusion layer of the higher impurity of the above-mentioned silicon substrate of concentration ratio;

Form with the surface of the above-mentioned p-type impurity diffusion layer of the rear side of above-mentioned silicon substrate the 2nd electrode be electrically connected by above-mentioned multiple peristome.

<9> solar cell device, it possesses:

Comprise monocrystalline silicon or polysilicon and there is the N-shaped silicon substrate at sensitive surface and the back side with above-mentioned sensitive surface opposition side;

Be formed at the p-type impurity diffusion layer of the sensitive surface side of above-mentioned silicon substrate;

Be formed at the 2nd electrode of the rear side of above-mentioned silicon substrate;

Be formed at the surface of the sensitive surface side of above-mentioned silicon substrate, there is multiple peristome and comprise the passivating film of aluminium oxide and niobium oxide; And

Be formed at the surface of the above-mentioned p-type impurity diffusion layer of the sensitive surface side of above-mentioned silicon substrate and form with the surface of the sensitive surface side of above-mentioned silicon substrate the 1st electrode be electrically connected by above-mentioned multiple peristome.

The solar cell device of <10> according to any one of <7> ~ <9>, wherein, the mass ratio (niobium oxide/aluminium oxide) of the niobium oxide in passivating film and aluminium oxide is 30/70 ~ 90/10.

The solar cell device of <11> according to any one of <7> ~ <10>, wherein, the above-mentioned niobium oxide in above-mentioned passivating film and total containing ratio of above-mentioned aluminium oxide are more than 90 quality %.

The silicon substrate of <12> mono-kind with passivating film, its there is silicon substrate and be arranged on above-mentioned silicon substrate whole or a part, passivating film according to any one of <1> ~ <5>.

According to above-mentioned reference implementation mode, the carrier lifetime of silicon substrate can be extended and realize having the passivating film of negative fixed charge with low cost.In addition, the application type material of the formation realizing this passivating film can be provided for.In addition, that employ this passivating film, that efficiency is high solar cell device can be realized with low cost.In addition, can carrier lifetime be extended and realize having the silicon substrate of the band passivating film of negative fixed charge with low cost.

The passivating film of present embodiment is the passivating film for silicon solar cell element, and it comprises aluminium oxide and niobium oxide.

In addition, in the present embodiment, by changing the composition of passivating film, thus the fixed charge amount that this film has can be controlled.

In addition, from the view point of making negative fixed charge stabilisation, the mass ratio of niobium oxide and aluminium oxide is more preferably 30/70 ~ 80/20.In addition, from the view point of making negative fixed charge more stabilisation, the mass ratio of niobium oxide and aluminium oxide more preferably 35/65 ~ 70/30.In addition, from the view point of taking into account the raising of carrier lifetime and negative fixed charge, the mass ratio of niobium oxide and aluminium oxide is preferably 50/50 ~ 90/10.

Niobium oxide in passivating film and the mass ratio of aluminium oxide can pass through energy dispersion-type X-ray spectroscopic methodology (EDX), SIMS analysis method (SIMS) and high-frequency inductive coupling plasma physique Zymography (ICP-MS) and measure.Concrete condition determination is as follows.Passivating film is dissolved in acid or aqueous alkali, this solution is made to become vaporific and import in Ar plasma, the light of releasing when the element be stimulated is got back to ground state carries out light splitting and measures wavelength and intensity, carries out the qualitative of element from the wavelength of gained, and carries out quantitatively from the intensity of gained.

Total containing ratio of the niobium oxide in passivating film and aluminium oxide is preferably more than 80 quality %, from the view point of maintaining superperformance, is more preferably more than 90 quality %.If the composition of the niobium oxide in passivating film and aluminium oxide becomes many, then the effect of negative fixed charge becomes large.

Total containing ratio of the niobium oxide in passivating film and aluminium oxide can be measured by combination thermogravimetry, x-ray fluorescence analysis, ICP-MS and X ray absorption spectrometry.Concrete condition determination is as follows.Utilize thermogravimetry to calculate the ratio of inorganic constituents, and utilize the ratio of fluorescent X-ray or ICP-MS analytical calculation niobium and aluminium, the ratio of oxide can utilize X ray absorption spectrometry to investigate.

In addition, from the view point of the adjustment of the raising of film quality, modulus of elasticity, composition except niobium oxide and aluminium oxide can be comprised as organic principle in passivating film.The existence of the organic principle in passivating film can be confirmed by the mensuration of the FT-IR of elementary analysis and film.

The containing ratio of the organic principle in passivating film is more preferably and is less than 10 quality % in passivating film, more preferably below 5 quality %, is particularly preferably below 1 quality %.

Passivating film also can obtain with the form of the heat treatment thing comprising the application type material of alumina precursor and niobium oxide precursor.Below the details of application type material is described.

The application type material of present embodiment comprises alumina precursor and niobium oxide precursor and for the formation of the solar cell device passivating film with silicon substrate.

As long as alumina precursor generates the material of aluminium oxide, then all can use without particular limitation.As alumina precursor, from the aspect making aluminium oxide be distributed to aspect on silicon substrate and chemical stability equably, preferably use the alumina precursor of organic system.As the example of the alumina precursor of organic system, aluminum isopropylate (structural formula: Al (OCH (CH can be enumerated ₃) ₂) ₃), (strain) high-purity chemical research institute SYM-AL04 etc.

As long as niobium oxide precursor generates the material of niobium oxide, then all can use without particular limitation.As niobium oxide precursor, from the view point of making niobium oxide be distributed to aspect on silicon substrate and chemical stability equably, preferably use the niobium oxide precursor of organic system.As the example of the niobium oxide precursor of organic system, ethanol niobium (V) (structural formula: Nb (OC can be enumerated ₂h ₅) ₅, molecular weight: 318.21), (strain) high-purity chemical research institute Nb-05 etc.

Use rubbing method or print process that the application type material of the alumina precursor of the niobium oxide precursor and organic system that comprise organic system is carried out film forming, and heat treatment (burning till) the removing organic principle after utilizing, can passivating film be obtained thus.Therefore, result passivating film also can be the passivating film comprising organic principle.

The structure of < solar cell device illustrates >

Be described with reference to the structure of Fig. 6 ~ Fig. 9 to the solar cell device of present embodiment.Fig. 6 ~ Fig. 9 is the cutaway view of the 1st configuration example employing the solar cell device of passivating film overleaf ~ the 4th configuration example representing present embodiment.

As the silicon substrate used in the present embodiment (crystalline silicon substrate, semiconductor substrate) 101, any one in monocrystalline silicon or polysilicon can be used.In addition any one, as silicon substrate 101, in the silicon metal that the silicon metal that conductivity type can be used to be p-type or conductivity type are N-shaped.From the view point of the effect playing present embodiment further, more suitably conductivity type is the silicon metal of p-type.

In following Fig. 6 ~ Fig. 9, the example using p-type monocrystalline silicon as silicon substrate 101 is described.In addition, can be arbitrary monocrystalline silicon or polysilicon for the monocrystalline silicon of this silicon substrate 101 or polysilicon, but preferably resistivity be monocrystalline silicon or the polysilicon of 0.5 Ω cm ~ 10 Ω cm.

As shown in Fig. 6 (the 1st configuration example), form the n-type diffusion layer 102 doped with V group elements such as phosphorus in the sensitive surface side (in figure upside, the 1st face) of p-type silicon substrate 101.And, between silicon substrate 101 and diffusion layer 102, form pn tie.At the sensitive surface antireflection films 103 such as the surface of diffusion layer 102 formation silicon nitride (SiN) film and the 1st electrode 105 (electrode of sensitive surface side, the 1st electrode, overlying electrode, sensitive surface electrode) employing silver (Ag) etc.Sensitive surface antireflection film 103 can also have the function as sensitive surface passivating film concurrently.By using SiN film, thus sensitive surface antireflection film and the function both sensitive surface passivating film can be had concurrently.

In addition, the solar cell device of present embodiment can have sensitive surface antireflection film 103, also can not have sensitive surface antireflection film 103.In addition, in order to be reduced in the reflectivity on surface, preferably form concaveconvex structure (texture structure) at the sensitive surface of solar cell device, the solar cell device of present embodiment can have texture structure, also can not have texture structure.

On the other hand, layer doped with the III such as aluminium, boron element and BSF (Back Surface Field, back surface field) layer 104 is formed in the rear side (in figure downside, the 2nd, the back side) of silicon substrate 101.But the solar cell device of present embodiment can have BSF layer 104, also can not have BSF layer 104.

In order to contact (electrical connection) with BSF layer 104 (without surface during BSF layer 104 being the rear side of silicon substrate 101), and form in the rear side of this silicon substrate 101 the 2nd electrode 106 (electrode of rear side, the 2nd electrode, backplate) be made up of aluminium etc.

And then, in Fig. 6 (the 1st configuration example), form in the part except the contact area (peristome OA) be electrically connected with the 2nd electrode 106 by BSF layer 104 (without surface during BSF layer 104 being the rear side of silicon substrate 101) passivating film (passivation layer) 107 comprising aluminium oxide and niobium oxide.The passivating film 107 of present embodiment can have negative fixed charge.Utilize this fixed charge, make the minority carrier in the charge carrier produced in silicon substrate 101 due to light and electron reflection return face side.Therefore, short circuit current increases, and can expect the raising of photoelectric conversion efficiency.

Then, the 2nd configuration example shown in Fig. 7 is described.In Fig. 6 (the 1st configuration example), 2nd electrode 106 is formed on whole on contact area (peristome OA) and passivating film 107, in Fig. 7 (the 2nd configuration example), only form the 2nd electrode 106 at contact area (peristome OA).Also the part only on contact area (peristome OA) and passivating film 107 can be adopted to form the formation of the 2nd electrode 106.Even if the solar cell device formed shown in Fig. 7, also can obtain the effect same with Fig. 6 (the 1st configuration example).

Then, the 3rd configuration example shown in Fig. 8 is described.In the 3rd configuration example shown in Fig. 8, BSF layer 104 is only formed in the part comprised with the rear side of the contact area of the 2nd electrode 106 (peristome OA portion), without the need to being formed on whole of rear side as shown in Fig. 6 (the 1st configuration example).Even if the solar cell device (Fig. 8) that this kind is formed, the effect same with Fig. 6 (the 1st configuration example) also can be obtained.In addition, according to the solar cell device of the 3rd configuration example of Fig. 8, BSF layer 104, namely there is the region of impurity less with the doped in concentrations profiled higher compared with silicon substrate 101, therefore, it is possible to obtain the photoelectric conversion efficiency higher than Fig. 6 (the 1st configuration example) by the III such as adulterated al, boron element.

Then, the 4th configuration example shown in Fig. 9 is described.In Fig. 8 (the 3rd configuration example), 2nd electrode 106 is formed on whole on contact area (peristome OA) and passivating film 107, in Fig. 9 (the 4th configuration example), only form the 2nd electrode 106 at contact area (peristome OA).Also the part only on contact area (peristome OA) and passivating film 107 can be adopted to form the formation of the 2nd electrode 106.Even if the solar cell device formed shown in Fig. 9, also can obtain the effect same with Fig. 8 (the 3rd configuration example).

In addition, when by utilizing print process to give the 2nd electrode 106 and at high temperature carrying out burning till and be formed at whole of rear side, in temperature-fall period, the warpage raised up easily is produced.This kind of warpage causes the breakage of solar cell device sometimes, and rate of finished products may be made to reduce.In addition, when the further filming of silicon substrate, the problem of warpage can become large.The reason of this warpage is: the thermal coefficient of expansion comprising the 2nd electrode 106 of metal (such as aluminium) is larger than silicon substrate, and the contraction in temperature-fall period also correspondingly becomes large, therefore produces stress.

According to above content, as Fig. 7 (the 2nd configuration example) and Fig. 9 (the 4th configuration example) not overleaf whole of side when forming the 2nd electrode 106, electrode structure, easily in upper and lower symmetry, not easily produces the stress caused by the difference of thermal coefficient of expansion, therefore preferably.But, preferably reflector is set in addition at this moment.

The method for making of < solar cell device illustrates >

Below, the example of manufacture method of solar cell device (Fig. 6 ~ Fig. 9) of the present embodiment with above-mentioned formation is described.But, the solar cell device that present embodiment is not limited to utilize the method for the following stated to be made into.

First, the surface of the silicon substrate 101 shown in Fig. 6 etc. forms texture structure.About the formation of texture structure, the two sides of silicon substrate 101 can be formed in, also only can be formed in one side (sensitive surface side).In order to form texture structure, first, silicon substrate 101 be impregnated in the potassium hydroxide through heating or the solution of NaOH, the damage layer of removing silicon substrate 101.Then, be impregnated into in potassium hydroxide and the isopropyl alcohol solution that is principal component, formed texture structure on the two sides of silicon substrate 101 or one side (sensitive surface side) thus.In addition, as mentioned above, the solar cell device of present embodiment can have texture structure, also can not have texture structure, therefore also can omit this operation.

Then, by silicon substrate 101 with after the solution washing of hydrochloric acid, hydrofluoric acid etc., by phosphorous oxychloride (POCl on silicon substrate 101 ₃) etc. thermal diffusion and the phosphorus-diffused layer (n formed as diffusion layer 102 ⁺layer).Phosphorus-diffused layer such as can be imparted to heat-treat on silicon substrate 101 and to it by the solution of the dopant material of the application type by comprising phosphorus and be formed.After heat treatment, utilize the acid removings such as hydrofluoric acid to be formed at the phosphorus glass layer on surface, form the phosphorus-diffused layer (n as diffusion layer 102 thus ⁺layer).There is no particular restriction for the method for formation phosphorus-diffused layer.Phosphorus-diffused layer is preferably the scope of 0.2 μm ~ 0.5 μm with the degree of depth on distance silicon substrate 101 surface and the mode that film resistor reaches the scope of 40 Ω/ ~ 100 Ω/ (ohm/square) is formed.

Then, give in the rear side of silicon substrate 101 solution comprising the application type dopant material of boron, aluminium etc., and it is heat-treated, form the BSF layer 104 of rear side thus.Imparting can use the method for silk screen printing, ink-jet, distribution (dispense), spin coating etc.After heat treatment, utilize hydrofluoric acid, hydrochloric acid etc. to remove the layer being formed at the boron glass, aluminium etc. at the back side, form BSF layer 104 thus.There is no particular restriction for the method for formation BSF layer 104.Preferably reach 10 with the scope of the concentration making boron, aluminium etc. ¹⁸cm ^-3~ 10 ²²cm ^-3mode form BSF layer 104, more preferably form BSF layer 104 with point-like or wire.In addition, the solar cell device of present embodiment can have BSF layer 104, also can not have BSF layer 104, therefore also can omit this operation.

In addition, when the diffusion layer 102 of sensitive surface and the BSF layer 104 at the back side all use the solution of application type dopant material to be formed, the solution of above-mentioned dopant material is imparted to respectively the two sides of silicon substrate 101, and forms the phosphorus-diffused layer (n as diffusion layer 102 together ⁺layer) and BSF layer 104, then, the phosphorus glass, boron glass etc. that are formed at surface can be removed together.

Then, diffusion layer 102 is formed the silicon nitride film as sensitive surface antireflection film 103.There is no particular restriction for the method for formation sensitive surface antireflection film 103.Sensitive surface antireflection film 103 is preferably to make the mode that thickness is the scope of 50 ~ 100nm, refractive index is the scope of 1.9 ~ 2.2 be formed.Sensitive surface antireflection film 103 is not limited to silicon nitride film, also can be silicon oxide film, pellumina, oxidation titanium film etc.The surperficial antireflection film 103 such as silicon nitride film can utilize the method such as plasma CVD, hot CVD to make, and preferably utilizes the plasma CVD that can form surperficial antireflection film 103 the temperature range of 350 DEG C ~ 500 DEG C to make.

Then, passivating film 107 is formed in the rear side of silicon substrate 101.Passivating film 107 comprises aluminium oxide and niobium oxide, such as, comprise to decompose alumina precursor that application type material is representative with the organic metal that heat treatment (burning till) can be utilized to obtain aluminium oxide and decompose application type material with the commercially available organic metal that heat treatment (burning till) can be utilized to obtain niobium oxide by imparting be the material (passivating material) of the niobium oxide precursor of representative and heat-treat (burning till) to be formed to it.

The formation of passivating film 107 such as can be carried out in such a way.Utilizing the hydrofluoric acid of concentration 0.049 quality % to eliminate the thick and application type material that one side rotary coating that the is p-type silicon substrate of 8 inches (20.32cm) (8 Ω cm ~ 12 Ω cm) is above-mentioned of 725 μm of natural oxide film in advance, hot plate carries out with 120 DEG C the prebake conditions of 3 minutes.Then, in a nitrogen atmosphere, the heat treatment of 1 hour is carried out with 650 DEG C.Now, the passivating film comprising aluminium oxide and niobium oxide is obtained.The thickness that the employing ellipsometer of the passivating film 107 utilizing above-mentioned method to be formed records is generally tens of about nm.

Utilize the methods such as silk screen printing, hectographic printing, the printing of employing ink-jet, the printing of employing distributor (dispenser), give above-mentioned application type material with the predetermined pattern comprising contact area (peristome OA).In addition, preferably: after giving above-mentioned application type material, with the scope of 80 DEG C ~ 180 DEG C to its carry out prebake conditions make solvent evaporate after, implement the heat treatment (annealing) of 30 minutes ~ 3 hours in a nitrogen atmosphere or in air with 600 DEG C ~ 1000 DEG C, make passivating film 107 (film of oxide).

And then, preferably on BSF layer 104, form peristome (hole of contact) OA with point-like or wire.

As the passivating film 107 used in above-mentioned solar cell device, the mass ratio (niobium oxide/aluminium oxide) preferably making niobium oxide and aluminium oxide is 30/70 ~ 90/10, is more preferably 30/70 ~ 80/20, more preferably 35/65 ~ 70/30.Negative fixed charge stabilisation can be made thus.In addition, from the view point of the raising of carrier lifetime and negative fixed charge can be taken into account, the mass ratio of niobium oxide and aluminium oxide is preferably made to be 50/50 ~ 90/10.

And then in passivating film 107, total containing ratio of niobium oxide and aluminium oxide is preferably more than 80 quality %, is more preferably more than 90 quality %.

Then, electrode i.e. the 1st electrode 105 of sensitive surface side is formed.1st electrode 105 is formed by utilizing silk screen printing to be formed on sensitive surface antireflection film 103 with silver (Ag) paste that is principal component and heat-treat (burning logical) to it.The shape of the 1st electrode 105 can be arbitrary shape, such as, can be the known shape formed by secondary grid line (finger) electrode and main gate line (bus bar) electrode.

Then, electrode i.e. the 2nd electrode 106 of rear side is formed.2nd electrode 106 can be formed by using silk screen printing or distributor to give with aluminium to be the paste of principal component and heat-treating it.In addition, the shape of the 2nd electrode 106 is preferably the shape identical with the shape of BSF layer 104, covers the shape, comb shape shape, clathrate etc. of whole of rear side.In addition, carry out the electrode i.e. printing of the paste of the 1st electrode 105 and the 2nd electrode 106 for the formation of sensitive surface side respectively in advance, afterwards it is heat-treated (burning logical), the 1st electrode 105 and the 2nd electrode 106 can be formed thus together.

In addition, when formation the 2nd electrode 106, the paste that to use with aluminium (Al) be principal component, makes aluminium spread as dopant thus, and forms BSF layer 104 at the 2nd electrode 106 with the contact site of silicon substrate 101 in the mode of ego integrity.In addition, as previously discussed, give in the rear side of silicon substrate 101 solution comprising the application type dopant material of boron, aluminium etc., and it is heat-treated, BSF layer 104 can be formed separately thus.

In addition, above-mentionedly show the structure example that employs p-type silicon in silicon substrate 101 and method for making example, also can be used as the N-shaped silicon substrate of silicon substrate 101.Now, diffusion layer 102 is formed by the layer doped with III elements such as boron, and BSF layer 104 is formed by V group elements such as Doping Phosphorus.But, now need to notice following some: sometimes because the part that the metal of the inversion layer with rear side that are formed at interface contacts is communicated with and the leakage current that circulates by negative fixed charge, be difficult to improve conversion efficiency.

In addition, when using N-shaped silicon substrate, the passivating film 107 comprising niobium oxide and aluminium oxide can be used as shown in Figure 10 in sensitive surface side.Figure 10 is the cutaway view of the configuration example of the solar cell device representing the sensitive surface passivating film employing present embodiment.

Now, diffusion layer 102 doped with boron of sensitive surface side and become p-type, makes void coalescence in generated charge carrier in sensitive surface side, and makes electron-collection side overleaf.Therefore, the passivating film 107 with negative fixed charge is preferably made to be positioned at sensitive surface side.

Also on the passivating film comprising niobium oxide and aluminium oxide, CVD etc. can be utilized further to form the antireflection film be made up of SiN etc.

Below, with reference to the reference example of present embodiment and be described in detail with reference to comparative example.

[reference example 1-1]

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd. SYM-AL04, concentration 2.3 quality %] 3.0g and heat treatment (burning till) can be utilized to obtain niobium oxide (Nb ₂o ₅) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd. Nb-05, concentration 5 quality %] 3.0g and mix, be prepared into the passivating material (a-1) as application type material.

Utilizing the hydrofluoric acid of concentration 0.049 quality % to eliminate the thick and one side rotary coating passivating material (a-1) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film in advance, hot plate carries out with 120 DEG C the prebake conditions of 3 minutes.Then, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 650 DEG C, obtain the passivating film [niobium oxide/aluminium oxide=68/32 (mass ratio)] comprising aluminium oxide and niobium oxide.The thickness utilizing ellipsometer to record is 43nm.Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (Metal-Insulator-Semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to+0.32V from ideal value-0.81V.From this displacement, it is-7.4 × 10 that the passivating film obtained by passivating material (a-1) demonstrates fixed charge density (Nf) ¹¹cm ^-2negative fixed charge.

As described above passivating material (a-1) is imparted to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 650 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of Kobe Steel of Co., Ltd., RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 530 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.

From above content, (burning till) is heat-treated to passivating material (a-1) and the passivating film display inactivating performance to a certain degree that obtains, and demonstrate negative fixed charge.

[reference example 1-2]

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd., SYM-AL04, concentration 2.3 quality %] and heat treatment (burning till) can be utilized to obtain niobium oxide (Nb ₂o ₅) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd., Nb-05, concentration 5 quality %] and change ratio and carry out mixing and being prepared into passivating material (a-2) ~ (a-7) shown in table 4 in the same manner as reference example 1-1.

In the same manner as reference example 1-1, passivating material (a-2) ~ (a-7) be imparted to the one side of p-type silicon substrate respectively and (burning till) heat-treated to it and is made into passivating film.The voltage-dependent of the static capacity of the passivating film of gained is measured, and calculates fixed charge density thus.

And then, passivating material be imparted to the two sides of p-type silicon substrate in the same manner as reference example 1-1 and (burning till) heat-treated to it and obtains sample, using the sample determination of gained carrier lifetime.The result of gained is summarized in table 4.

According to the difference of the ratio (mass ratio) of the niobium oxide/aluminium oxide after heat treatment (burning till), result is different, but the carrier lifetime of passivating material (a-2) ~ (a-7) after heat treatment (burning till) also demonstrates value to a certain degree, therefore means that it plays function as passivating film.Visible: the passivating film obtained by passivating material (a-2) ~ (a-7) all stably shows negative fixed charge, also can be suitable as the passivating film of p-type silicon substrate.

[table 4]

[reference example 1-3]

By commercially available ethanol niobium (V) (structural formula: Nb (OC ₂h ₅) ₅, molecular weight: 318.21) 3.18g (0.010mol) and commercially available aluminum isopropylate (structural formula: Al (OCH (CH ₃) ₂) ₃, molecular weight: 204.25) 1.02g (0.005mol) is dissolved in cyclohexane 80g, is prepared into the passivating material (c-1) of concentration 5 quality %.

Utilizing the hydrofluoric acid of concentration 0.049 quality % to eliminate the thick and one side rotary coating passivating material (c-1) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film in advance, hot plate carries out with 120 DEG C the prebake conditions of 3 minutes.Then, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, obtain the passivating film comprising aluminium oxide and niobium oxide.The thickness utilizing ellipsometer to record is 50nm.The result of visual elements analysis is Nb/Al/C=81/14/5 (quality %).Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (Metal-Insulator-Semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to+4.7V from ideal value-0.81V.From this displacement, it is-3.2 × 10 that the passivating film obtained by passivating material (c-1) demonstrates fixed charge density (Nf) ¹²cm ^-2negative fixed charge.

As described above passivating material (c-1) is imparted to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of Kobe Steel of Co., Ltd., RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 330 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.

From above content, (burning till) is heat-treated to passivating material (c-1) and the passivating film display inactivating performance to a certain degree that obtains, and demonstrate negative fixed charge.

[reference example 1-4]

By commercially available ethanol niobium (V) (structural formula: Nb (OC ₂h ₅) ₅, molecular weight: 318.21) 2.35g (0.0075mol), commercially available aluminum isopropylate (structural formula: Al (OCH (CH ₃) ₂) ₃, molecular weight: 204.25) 1.02g (0.005mol) and linear phenol-aldehyde resin 10g is dissolved in diethylene glycol monobutyl ether acetic acid esters 10g and cyclohexane 10g, is prepared into passivating material (c-2).

Utilizing the hydrofluoric acid of concentration 0.049 quality % to eliminate the thick and one side rotary coating passivating material (c-2) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film in advance, hot plate carries out with 120 DEG C the prebake conditions of 3 minutes.Then, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, obtain the passivating film comprising aluminium oxide and niobium oxide.The thickness utilizing ellipsometer to record is 14nm.The result of visual elements analysis is Nb/Al/C=75/17/8 (quality %).Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (Metal-Insulator-Semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to+0.10V from ideal value-0.81V.From this displacement, it is-0.8 × 10 that the passivating film obtained by passivating material (c-2) demonstrates fixed charge density (Nf) ¹¹cm ^-2negative fixed charge.

As described above passivating material (c-2) is imparted to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of Kobe Steel of Co., Ltd., RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 200 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.

From above content, the passivating film display inactivating performance to a certain degree obtained by passivating material (c-2), and the negative fixed charge of display.

[reference example 1-5 and reference comparative example 1-1]

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd. SYM-AL04, concentration 2.3 quality %] and heat treatment (burning till) can be utilized to obtain niobium oxide (Nb ₂o ₅) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd. Nb-05, concentration 5 quality %] and change ratio and carry out mixing and being prepared into passivating material (b-1) ~ (b-7) shown in table 5 in the same manner as reference example 1-1.

In the same manner as reference example 1-1, passivating material (b-1) ~ (b-7) be imparted to the one side of p-type silicon substrate respectively and (burning till) heat-treated to it and is made into passivating film, use this passivating film to measure the voltage-dependent of static capacity, and calculate fixed charge density thus.

And then, in the same manner as reference example 1-1, passivating material (application type material) be imparted to the two sides of p-type silicon substrate and make it solidify and obtain sample, using the sample determination carrier lifetime of gained.The result of gained is summarized in table 5.

[table 5]

Visible: for the passivating film obtained by passivating material (b-1) ~ (b-6), all comparatively large and function had as passivating film of its carrier lifetime.In addition, when niobium oxide/aluminium oxide is 10/90 and 20/80, there is relatively large deviation with the value of determining charge density, cannot stably obtain negative fixed charge density, but can confirm and can realize negative fixed charge density by using aluminium oxide and niobium oxide.Visible: when using niobium oxide/aluminium oxide be the passivating material of 10/90 and 20/80 and utilize CV method to measure, according to circumstances to become the passivating film showing positive fixed charge, therefore do not reach the negative fixed charge of stably display.In addition, the passivating film showing positive fixed charge can use as the passivating film of N-shaped silicon substrate.

On the other hand, the passivating material (b-7) that aluminium oxide reaches 100 quality % cannot obtain negative fixed charge density.

[with reference to comparative example 1-2]

The utilized heat treatment (burning till) prepared as passivating material (d-1) obtains titanium oxide (TiO ₂) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd. Ti-03-P, concentration 3 quality %], obtain barium titanate (BaTiO as the utilized heat treatment (burning till) of passivating material (d-2) ₃) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd. BT-06, concentration 6 quality %] and obtain hafnium oxide (HfO as the utilized heat treatment (burning till) of passivating material (d-3) ₂) commercially available organic metal decompose application type material [high-purity chemical research institute of Co., Ltd. Hf-05, concentration 5 quality %].

Passivating material (d-1) ~ (d-3) is imparted to respectively the one side of p-type silicon substrate in the same manner as reference example 1-1, then (burning till) heat-treated to it and be made into passivating film, use this passivating film to measure the voltage-dependent of static capacity, and calculate fixed charge density thus.

And then, passivating material be imparted to the two sides of p-type silicon substrate in the same manner as reference example 1-1 and (burning till) heat-treated to it and obtains sample, using the sample determination of gained carrier lifetime.The result of gained is summarized in table 6.

[table 6]

Visible: for the passivating film obtained by passivating material (d-1) ~ (d-3), its carrier lifetime is all less and insufficient as the function of passivating film.In addition, positive fixed charge is demonstrated.By passivating material (d-3) although the passivating film obtained is negative fixed charge, its value is less.In addition, carrier lifetime is also less, insufficient as the function of passivating film.

[reference example 1-6]

To use doped with the monocrystalline silicon substrate of boron as silicon substrate 101, be made into the solar cell device of structure shown in Fig. 8.After texture processing is carried out to the surface of silicon substrate 101, the phosphorus diffusion material of application type is imparted to sensitive surface side, and utilizes heat treatment to form diffusion layer 102 (phosphorus-diffused layer).Afterwards, diluted hydrofluoric acid is utilized to remove the phosphorus diffusion material of application type.

Then, formed in sensitive surface side utilize plasma CVD to be made into SiN film as sensitive surface antireflection film 103.Then, ink-jet method is utilized to be imparted to the region except contact area (peristome OA) of the rear side of silicon substrate 101 with reference to passivating material (a-1) obtained in embodiment 1-1.Then, it is heat-treated, form the passivating film 107 with peristome OA.

In addition, as passivating film 107, the sample using passivating material (c-1) obtained in reference example 1-3 has also been made separately.

Then, the sensitive surface antireflection film 103 (SiN film) of sensitive surface side being formed at silicon substrate 101 with the secondary gate line electrode of regulation and the shape silk screen printing of main gate line electrode with silver is the paste of principal component.Whole silk screen printing of side take aluminium as the paste of principal component overleaf.Then, heat-treat (burning logical) with 850 DEG C, form electrode (the 1st electrode 105 and the 2nd electrode 106), and make aluminium be diffused into the part of the peristome OA at the back side, form BSF layer 104, thus form the solar cell device of structure shown in Fig. 8.

In addition, at this, about the silver electrode of sensitive surface, the burning describing not perforate in SiN film leads to operation, but in SiN film, etching also can be utilized in advance to wait formation peristome OA, forms silver electrode afterwards.

In order to compare, in above-mentioned production process, do not carry out the formation of passivating film 107, and whole of side printing Aluminum Paste overleaf, and form the p corresponding with BSF layer 104 at whole ⁺layer 114 and the electrode 116 of answering with the 2nd electrode pair, form the solar cell device of structure shown in Fig. 5.Evaluating characteristics (short circuit current, open circuit voltage, Fill factor and conversion efficiency) has been carried out to these solar cell devices.Evaluating characteristics measures according to JIS-C-8913 (2005 year) and JIS-C-8914 (2005 year).The results are shown in table 7.

Shown by table 7, if will there is the solar cell device of the passivating film 107 comprising niobium oxide and alumina layer compared with not there is the solar cell device of passivating film 107, then short circuit current and open circuit voltage all increase, the maximum raising 1% of conversion efficiency (photoelectric conversion efficiency).

[table 7]

< reference implementation mode 2>

It is below the silicon substrate of the passivating film of reference implementation mode 2, application type material, solar cell device and band passivating film.

<1> passivating film, its vanadium family element oxide comprising aluminium oxide and be selected from least one in vanadium oxide and tantalum oxide, and for having the solar cell device of silicon substrate.

The passivating film of <2> according to <1>, wherein, the mass ratio (vanadium family element oxide/aluminium oxide) of above-mentioned vanadium family element oxide and above-mentioned aluminium oxide is 30/70 ~ 90/10.

The passivating film of <3> according to <1> or <2>, wherein, total containing ratio of above-mentioned vanadium family element oxide and above-mentioned aluminium oxide is more than 90%.

The passivating film of <4> according to any one of <1> ~ <3>, wherein, as above-mentioned vanadium family element oxide, comprise the vanadium family element oxide being selected from vanadium oxide, niobium oxide and tantalum oxide 2 kinds or 3 kinds.

The passivating film of <5> according to any one of <1> ~ <4>, it is the heat treatment thing of the application type material of the precursor of the salic precursor of bag and the vanadium family element oxide being selected from least one in the precursor of vanadium oxide and the precursor of tantalum oxide.

<6> application type material, its precursor of vanadium family element oxide wrapping salic precursor and be selected from least one in the precursor of vanadium oxide and the precursor of tantalum oxide, and for the formation of having the passivating film of solar cell device of silicon substrate.

<7> solar cell device, it possesses:

P-type silicon substrate;

Be formed at the sensitive surface side i.e. N-shaped impurity diffusion layer of the 1st side of above-mentioned silicon substrate;

Be formed at the 1st electrode on above-mentioned impurity diffusion layer;

Be formed at 2nd side contrary with sensitive surface side of above-mentioned silicon substrate and there is the passivating film of peristome; And

Be formed at the 2nd side of above-mentioned silicon substrate and the 2nd electrode be electrically connected with the 2nd side of above-mentioned silicon substrate by the peristome of above-mentioned passivating film,

Above-mentioned passivating film comprises aluminium oxide and is selected from the vanadium family element oxide of at least one in vanadium oxide and tantalum oxide.

The solar cell device of <8> according to <7>, it has part or all of the 2nd side being formed at above-mentioned silicon substrate and is added with the p-type impurity diffusion layer of the higher impurity of the above-mentioned silicon substrate of concentration ratio

Above-mentioned 2nd electrode is electrically connected with above-mentioned p-type impurity diffusion layer by the peristome of above-mentioned passivating film.

<9> solar cell device, it possesses:

N-shaped silicon substrate;

Be formed at the sensitive surface side i.e. p-type impurity diffusion layer of the 1st side of above-mentioned silicon substrate;

Be formed at the 1st electrode on above-mentioned impurity diffusion layer;

The solar cell device of <10> according to <9>, it has part or all of the 2nd side being formed at above-mentioned silicon substrate and is added with the N-shaped impurity diffusion layer of the higher impurity of the above-mentioned silicon substrate of concentration ratio

Above-mentioned 2nd electrode is electrically connected with said n type impurity diffusion layer by the peristome of above-mentioned passivating film.

The solar cell device of <11> according to any one of <7> ~ <10>, wherein, the above-mentioned vanadium family element oxide of above-mentioned passivating film and the mass ratio of above-mentioned aluminium oxide are 30/70 ~ 90/10.

The solar cell device of <12> according to any one of <7> ~ <11>, wherein, the above-mentioned vanadium family element oxide of above-mentioned passivating film and total containing ratio of above-mentioned aluminium oxide are more than 90%.

The solar cell device of <13> according to any one of <7> ~ <12>, wherein, as above-mentioned vanadium family element oxide, comprise the vanadium family element oxide being selected from vanadium oxide, niobium oxide and tantalum oxide 2 kinds or 3 kinds.

The silicon substrate of <14> mono-kind with passivating film, its there is silicon substrate and be arranged on above-mentioned silicon substrate whole or a part, solar cell device passivating film according to any one of <1> ~ <5>.

According to above-mentioned reference implementation mode, the carrier lifetime of silicon substrate can be extended and realize having the passivating film of negative fixed charge with low cost.In addition, the application type material of the formation realizing this passivating film can be provided for.In addition, that employ this passivating film, that efficiency is high solar cell device can be realized with low cost.In addition, the carrier lifetime of silicon substrate can be extended and realize having the silicon substrate of the band passivating film of negative fixed charge with low cost.

The passivating film of present embodiment is the passivating film for silicon solar cell element, and it comprises aluminium oxide and is selected from least one vanadium family element oxide in vanadium oxide and tantalum oxide.

In addition, in the present embodiment, by changing the composition of passivating film, thus the amount of the fixed charge that passivating film has can be controlled.At this, vanadium family element is the 5th race's element of the periodic table of elements, and it is the element being selected from vanadium, niobium and tantalum.

In addition, from the view point of making negative fixed charge stabilisation, the mass ratio of vanadium family element oxide and aluminium oxide is more preferably 35/65 ~ 90/10, and more preferably 50/50 ~ 90/10.

Vanadium family element oxide in passivating film and the mass ratio of aluminium oxide can pass through energy dispersion-type X-ray spectroscopic methodology (EDX), SIMS analysis method (SIMS) and high-frequency inductive coupling plasma physique Zymography (ICP-MS) and measure.Concrete condition determination is as described below when such as ICP-MS.Passivating film is dissolved in acid or aqueous alkali, this solution is made to become vaporific and import in Ar plasma, the light of releasing when the element be stimulated is got back to ground state carries out light splitting and measures wavelength and intensity, carries out the qualitative of element from the wavelength of gained, and carries out quantitatively from the intensity of gained.

Vanadium family element oxide in passivating film and total containing ratio of aluminium oxide are preferably more than 80 quality %, from the view point of maintaining superperformance, are more preferably more than 90 quality %.If the composition except vanadium family element oxide and aluminium oxide in passivating film becomes many, then the effect of negative fixed charge becomes large.

In addition, from the view point of the raising of film quality and the adjustment of modulus of elasticity, composition except vanadium family element oxide and aluminium oxide can be comprised as organic principle in passivating film.The existence of the organic principle in passivating film can be confirmed by the mensuration of the FT-IR of elementary analysis and film.

As above-mentioned vanadium family element oxide, from the view point of obtaining larger negative fixed charge, preferred selective oxidation vanadium (V ₂o ₅).

Above-mentioned passivating film can comprise be selected from vanadium oxide, niobium oxide and tantalum oxide 2 kinds or 3 kinds vanadium family element oxide as vanadium family element oxide.

Above-mentioned passivating film obtains preferably by heat-treating application type material, application type material is carried out film forming more particularly by use rubbing method or print process, utilizes heat treatment afterwards and remove organic principle to obtain.That is, passivating film also can obtain with the form of the heat treatment thing comprising the application type material of the precursor of alumina precursor and vanadium family element oxide.Hereinafter describe carrying out the details of application type material.

The application type material of present embodiment is the application type material of the passivating film of the solar cell device for having silicon substrate, its precursor of vanadium family element oxide wrapping salic precursor and be selected from least one in the precursor of vanadium oxide and the precursor of tantalum oxide.As the precursor of the vanadium family element oxide contained by application type material, the negative fixed charge of the passivating film formed from the view point of utilizing coating material, preferred selective oxidation vanadium (V ₂o ₅) precursor.Application type material can comprise the precursor of precursor as vanadium family element oxide of the vanadium family element oxide of in the precursor being selected from the precursor of vanadium oxide, the precursor of niobium oxide and tantalum oxide 2 kinds or 3 kinds.

As long as alumina precursor generates the material of aluminium oxide, then all can use without particular limitation.As alumina precursor, from the view point of making aluminium oxide evenly spread to aspect on silicon substrate and chemical stability, preferably use the alumina precursor of organic system.As the example of the alumina precursor of organic system, aluminum isopropylate (structural formula: Al (OCH (CH can be enumerated ₃) ₂) ₃), (strain) high-purity chemical research institute SYM-AL04.

As long as the precursor of vanadium family element oxide generates the material of vanadium family element oxide, then all can use without particular limitation.As the precursor of vanadium family element oxide, from the view point of making aluminium oxide be distributed to aspect on silicon substrate and chemical stability equably, preferably use the precursor of the vanadium family element oxide of organic system.

As the example of the precursor of the vanadium oxide of organic system, triethoxy vanadium oxide (V) (structural formula: VO (OC can be enumerated ₂h ₅) ₃, molecular weight: 202.13), (strain) high-purity chemical research institute V-02.As the example of the precursor of the tantalum oxide of organic system, methyl alcohol tantalum (V) (structural formula: Ta (OCH can be enumerated ₃) ₅, molecular weight: 336.12), (strain) high-purity chemical research institute Ta-10-P.As the example of the niobium oxide precursor of organic system, ethanol niobium (V) (structural formula: Nb (OC can be enumerated ₂h ₅) ₅, molecular weight: 318.21), (strain) high-purity chemical research institute Nb-05.

Use rubbing method or print process that the application type material of the precursor of vanadium family element oxide and the alumina precursor of organic system that comprise organic system is carried out film forming, and the heat treatment removing organic principle after utilizing, can passivating film be obtained thus.Therefore, result passivating film also can be the passivating film comprising organic principle.The containing ratio of the organic principle in passivating film is more preferably and is less than 10 quality %, more preferably below 5 quality %, is particularly preferably below 1 quality %.

The solar cell device (photoelectric conversion device) of present embodiment have near the opto-electronic conversion interface of silicon substrate illustrate in above-mentioned execution mode passivating film (dielectric film, protection dielectric film), namely comprise aluminium oxide and be selected from the film of at least one vanadium family element oxide in vanadium oxide and tantalum oxide.By comprising aluminium oxide and the vanadium family element oxide being selected from least one in vanadium oxide and tantalum oxide, thus the carrier lifetime of silicon substrate can be extended and there is negative fixed charge, and the characteristic (photoelectric conversion efficiency) of solar cell device can be improved.

The structure of the solar cell device of present embodiment illustrates and method for making illustrates and can illustrate and method for making explanation with reference to the structure of the solar cell device of reference implementation mode 1.

< uses vanadium oxide as the situation > of vanadium family element oxide

[reference example 2-1]

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, SYM-AL04, concentration 2.3 quality %] 3.0g and heat treatment (burning till) can be utilized to obtain vanadium oxide (V ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, V-02, concentration 2 quality %] 6.0g mix, be prepared into the passivating material (a2-1) as application type material.

Thick and the one side rotary coating passivating material (a2-1) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film is eliminated utilizing the hydrofluoric acid of concentration 0.49 quality % in advance, be positioned on hot plate, carried out the prebake conditions of 3 minutes with 120 DEG C.Then, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 30 minutes with 700 DEG C, obtain the passivating film [vanadium oxide/aluminium oxide=63/37 (quality %)] comprising aluminium oxide and vanadium oxide.The thickness utilizing ellipsometer to record is 51nm.Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (metal-insulator-semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to+0.02V from ideal value-0.81V.From this displacement, it is-5.2 × 10 that the passivating film obtained by passivating material (a2-1) demonstrates fixed charge density (Nf) ¹¹cm ^-2negative fixed charge.

As described above passivating material (a2-1) is applied to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 650 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of (strain) Kobe Steel, RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 400 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.In addition, again determine carrier lifetime after 14 days after making sample, result carrier lifetime is 380 μ s.It can thus be appreciated that the reduction (from 400 μ s to 380 μ s) of carrier lifetime is within-10%, and the reduction of carrier lifetime is less.

From above content, (burning till) is heat-treated to passivating material (a2-1) and the passivating film display inactivating performance to a certain degree that obtains, and demonstrate negative fixed charge.

[reference example 2-2]

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, SYM-AL04, concentration 2.3 quality %] and heat treatment can be utilized to obtain vanadium oxide (V ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, V-02, concentration 2 quality %] change ratio and carry out mixing and being prepared into passivating material (a2-2) ~ (a2-7) shown in table 8 in the same manner as reference example 2-1.

In the same manner as reference example 2-1, passivating material (a2-2) ~ (a2-7) be applied to the one side of p-type silicon substrate respectively and (burning till) heat-treated to it and is made into passivating film.The voltage-dependent of the static capacity of the passivating film of gained is measured, and calculates fixed charge density thus.

And then, passivating material be applied to the two sides of p-type silicon substrate in the same manner as reference example 2-1 and (burning till) heat-treated to it and obtains sample, using the sample determination of gained carrier lifetime.

The result of gained is summarized in table 8.In addition known, again carrier lifetime is determined after 14 days after making sample, result uses the reduction of the carrier lifetime of the passivating film of passivating material (a2-2) ~ (a2-7) shown in table 8 to be within-10%, and the reduction of carrier lifetime is less.

According to the difference of the ratio (mass ratio) of the vanadium oxide/aluminium oxide after heat treatment (burning till), result is different, but passivating material (a2-2) ~ (a2-7) all shows negative fixed charge after heat treatment (burning till), and carrier lifetime also shows value to a certain degree, therefore mean that it plays function as passivating film.Visible: the passivating film obtained by passivating material (a2-2) ~ (a2-7) all stably shows negative fixed charge, also can be suitable as the passivating film of p-type silicon substrate.

[table 8]

[reference example 2-3]

Vanadium oxide (V will be obtained as utilizing heat treatment (burning till) ₂o ₅) commercially available triethoxy vanadium oxide (the V) (structural formula: VO (OC of compound ₂h ₅) ₃, molecular weight: 202.13) 1.02g (0.010mol) and as heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available aluminum isopropylate (structural formula: the Al (OCH (CH of compound ₃) ₂) ₃, molecular weight: 204.25) 2.04g (0.010mol) is dissolved in cyclohexane 60g, is prepared into the passivating material (b2-1) of concentration 5 quality %.

Utilizing the hydrofluoric acid of concentration 0.49 quality % to eliminate the thick and one side rotary coating passivating material (b2-1) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film in advance, hot plate carries out with 120 DEG C the prebake conditions of 3 minutes.Afterwards, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 650 DEG C, obtain the passivating film comprising aluminium oxide and vanadium oxide.The thickness utilizing ellipsometer to record is 60nm.The result of visual elements analysis is V/Al/C=64/33/3 (quality %).Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (metal-insulator-semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to+0.10V from ideal value-0.81V.From this displacement, it is-6.2 × 10 that the passivating film obtained by passivating material (b2-1) demonstrates fixed charge density (Nf) ¹¹cm ^-2negative fixed charge.

As described above passivating material (b2-1) is applied to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of (strain) Kobe Steel, RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 400 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.

From above content, (burning till) is heat-treated to passivating material (b2-1) and the passivating film display inactivating performance to a certain degree that obtains, and demonstrate negative fixed charge.

[reference example 2-4]

By commercially available triethoxy vanadium oxide (V) (structural formula: VO (OC ₂h ₅) ₃, molecular weight: 202.13) 1.52g (0.0075mol), commercially available aluminum isopropylate (structural formula: Al (OCH (CH ₃) ₂) ₃, molecular weight: 204.25) 1.02g (0.005mol) and linear phenol-aldehyde resin 10g is dissolved in diethylene glycol monobutyl ether acetic acid esters 10g and cyclohexane 10g, is prepared into passivating material (b2-2).

Thick and the one side rotary coating passivating material (b2-2) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film is eliminated utilizing the hydrofluoric acid of concentration 0.49 quality % in advance, be positioned on hot plate, carried out the prebake conditions of 3 minutes with 120 DEG C.Then, in a nitrogen atmosphere, carry out the heating of 1 hour with 650 DEG C, obtain the passivating film comprising aluminium oxide and vanadium oxide.The thickness utilizing ellipsometer to record is 22nm.The result of visual elements analysis is V/Al/C=71/22/7 (quality %).Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (metal-insulator-semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to+0.03V from ideal value-0.81V.From this displacement, it is-2.0 × 10 that the passivating film obtained by passivating material (b2-2) demonstrates fixed charge density (Nf) ¹¹cm ^-2negative fixed charge.

As described above passivating material (b2-2) is applied to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of (strain) Kobe Steel, RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 170 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.

From above content, passivating material (b2-2) is solidified and the passivating film that obtain shows inactivating performance to a certain degree, and demonstrate negative fixed charge.

< uses tantalum oxide as the situation > of vanadium family element oxide

[reference example 2-5]

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, SYM-AL04, concentration 2.3 quality %] and heat treatment can be utilized to obtain tantalum oxide (Ta ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, Ta-10-P, concentration 10 quality %] change ratio and mix, be prepared into passivating material (c2-1) ~ (c2-6) shown in table 9.

Thick and the one side of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) rotary coating passivating material (c2-1) ~ (c2-6) respectively of 725 μm of natural oxide film is eliminated utilizing the hydrofluoric acid of concentration 0.49 quality % in advance, be positioned on hot plate, carried out the prebake conditions of 3 minutes with 120 DEG C.Then, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 30 minutes with 700 DEG C, obtain the passivating film comprising aluminium oxide and tantalum oxide.Use this passivating film to measure the voltage-dependent of static capacity, and calculate fixed charge density thus.

Then, passivating material (c2-1) ~ (c2-6) is coated respectively the two sides of the p-type silicon substrate of 8 inches and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 650 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of (strain) Kobe Steel, RTA-540) is utilized to determine the carrier lifetime of this sample.

The result of gained is summarized in table 9.In addition known, again carrier lifetime is determined after 14 days after making sample, result uses the reduction of the carrier lifetime of the passivating film of passivating material (c2-1) ~ (c2-6) shown in table 9 to be within-10%, and the reduction of carrier lifetime is less.

According to the difference of the ratio (mass ratio) of the tantalum oxide/aluminium oxide after heat treatment (burning till), result is different, but passivating material (c2-1) ~ (c2-6) all shows negative fixed charge after heat treatment (burning till), and carrier lifetime also shows value to a certain degree, therefore mean that it plays function as passivating film.

[table 9]

[reference example 2-6]

Tantalum oxide (Ta will be obtained as utilizing heat treatment (burning till) ₂o ₅) commercially available methyl alcohol tantalum (the V) (structural formula: Ta (OCH of compound ₃) ₅, molecular weight: 336.12) 1.18g (0.0025mol) and as heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available aluminum isopropylate (structural formula: the Al (OCH (CH of compound ₃) ₂) ₃, molecular weight: 204.25) 2.04g (0.010mol) is dissolved in cyclohexane 60g, is prepared into the passivating material (d2-1) of concentration 5 quality %.

Thick and the one side rotary coating passivating material (d2-1) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film is eliminated utilizing the hydrofluoric acid of concentration 0.49 quality % in advance, be positioned on hot plate, carried out the prebake conditions of 3 minutes with 120 DEG C.Then, in a nitrogen atmosphere, carry out the heating of 1 hour with 700 DEG C, obtain the passivating film comprising aluminium oxide and tantalum oxide.The thickness utilizing ellipsometer to record is 40nm.The result of visual elements analysis is Ta/Al/C=75/22/3 (wt%).Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (metal-insulator-semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to-0.30V from ideal value-0.81V.From this displacement, it is-6.2 × 10 that the passivating film obtained by passivating material (d2-1) demonstrates fixed charge density (Nf) ¹⁰cm ^-2negative fixed charge.

As described above passivating material (d2-1) is applied to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of (strain) Kobe Steel, RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 610 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.

From above content, (burning till) is heat-treated to passivating material (d2-1) and the passivating film display inactivating performance to a certain degree that obtains, and demonstrate negative fixed charge.

[reference example 2-7]

Tantalum oxide (Ta will be obtained as utilizing heat treatment (burning till) ₂o ₅) commercially available methyl alcohol tantalum (the V) (structural formula: Ta (OCH of compound ₃) ₅, molecular weight: 336.12) 1.18g (0.005mol), as heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available aluminum isopropylate (structural formula: the Al (OCH (CH of compound ₃) ₂) ₃, molecular weight: 204.25) 1.02g (0.005mol) and linear phenol-aldehyde resin 10g is dissolved in the mixture of diethylene glycol monobutyl ether acetic acid esters 10g and cyclohexane 10g, is prepared into passivating material (d2-2).

Utilizing the hydrofluoric acid of concentration 0.49 quality % to eliminate the thick and one side rotary coating passivating material (d2-2) of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) of 725 μm of natural oxide film in advance, hot plate carries out with 120 DEG C the prebake conditions of 3 minutes.Then, in a nitrogen atmosphere, carry out the heating of 1 hour with 650 DEG C, obtain the passivating film comprising aluminium oxide and tantalum oxide.The thickness utilizing ellipsometer to record is 18nm.The result of visual elements analysis is Ta/Al/C=72/20/8 (wt%).Measure the FT-IR of passivating film, result is at 1200cm ^-1near observe the extremely weak peak being derived from alkyl.

Then, above-mentioned passivating film utilizes evaporation to form the aluminium electrode of multiple diameter 1mm across metal mask, is made into MIS (metal-insulator-semiconductor; Metal-insulator semiconductor) capacitor of structure.Commercially available detector and LCR meter (Hewlett-Packard Corporation, 4275A) is utilized to measure the voltage-dependent (C-V characteristic) of the static capacity of this capacitor.Result shows: flat band voltage (Vfb) is moved to-0.43V from ideal value-0.81V.From this displacement, it is-5.5 × 10 that the passivating film obtained by passivating material (d-2) demonstrates fixed charge density (Nf) ¹⁰cm ^-2negative fixed charge.

As described above passivating material (d2-2) is applied to the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 600 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of (strain) Kobe Steel, RTA-540) is utilized to determine the carrier lifetime of this sample.Result carrier lifetime is 250 μ s.In order to compare, utilize iodine deactivation method make the identical p-type silicon substrate passivation of 8 inches and measure it, result carrier lifetime is 1100 μ s.

From above content, (burning till) is heat-treated to passivating material (d2-2) and the passivating film display inactivating performance to a certain degree that obtains, and demonstrate negative fixed charge.

< uses the situation > of vanadium family element oxide of more than two kinds

[reference example 2-8]

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, SYM-AL04, concentration 2.3 quality %], heat treatment (burning till) can be utilized to obtain vanadium oxide (V ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, V-02, concentration 2 quality %] and heat treatment (burning till) can be utilized to obtain tantalum oxide (Ta ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, Ta-10-P, concentration 10 quality %] mixing, be prepared into the passivating material (e2-1) (with reference to table 10) as application type material.

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute SYM-AL04, concentration 2.3 quality %], heat treatment (burning till) can be utilized to obtain vanadium oxide (V ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute V-02, concentration 2 quality %] and heat treatment (burning till) can be utilized to obtain niobium oxide (Nb ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, Nb-05, concentration 5 quality %] mixing, be prepared into the passivating material (e2-2) (with reference to table 10) as application type material.

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute SYM-AL04, concentration 2.3 quality %], heat treatment (burning till) can be utilized to obtain tantalum oxide (Ta ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute Ta-10-P, concentration 10 quality %] and heat treatment (burning till) can be utilized to obtain niobium oxide (Nb ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute Nb-05, concentration 5 quality %] mixing, be prepared into the passivating material (e2-3) (with reference to table 10) as application type material.

Heat treatment (burning till) can be utilized to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute SYM-AL04, concentration 2.3 quality %], heat treatment (burning till) can be utilized to obtain vanadium oxide (V ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute V-02, concentration 2 quality %], heat treatment (burning till) can be utilized to obtain tantalum oxide (Ta ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute Ta-10-P, concentration 10 quality %] and heat treatment (burning till) can be utilized to obtain niobium oxide (Nb ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute Nb-05, concentration 5 quality %] mixing, be prepared into the passivating material (e2-4) (with reference to table 10) as application type material.

The hydrofluoric acid of concentration 0.49 quality % is being utilized to eliminate the thick and one side of the p-type silicon substrate of 8 inches (8 Ω cm ~ 12 Ω cm) rotary coating passivating material (e2-1) ~ (e2-4) respectively of 725 μm of natural oxide film in advance in the same manner as reference example 2-1, be positioned on hot plate, carried out the prebake conditions of 3 minutes with 120 DEG C.Then, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 650 DEG C, obtain the passivating film comprising aluminium oxide and vanadium family element oxide of more than two kinds.

Use passivating film obtained above to measure the voltage-dependent of static capacity, and calculate fixed charge density thus.

Then, passivating material (e2-1) ~ (e2-4) is coated respectively the two sides of the p-type silicon substrate of 8 inches, and prebake conditions is carried out to it, in a nitrogen atmosphere, carry out the heat treatment (burning till) of 1 hour with 650 DEG C, the two sides being made into silicon substrate is passivated the sample of film covering.Biometrics device (scientific research of (strain) Kobe Steel, RTA-540) is utilized to determine the carrier lifetime of this sample.

The result of gained is summarized in table 10.

Different according to the ratio (mass ratio) of the vanadium family element oxide of more than two kinds after heat treatment (burning till) and aluminium oxide, result is different, but the passivating film being the use of passivating material (e2-1) ~ (e2-4) all shows negative fixed charge after heat treatment (burning till), and carrier lifetime also shows value to a certain degree, therefore mean that it plays function as passivating film.

[table 10]

[reference example 2-9]

Heat treatment (burning till) can be utilized in the same manner as reference example 2-1 to obtain aluminium oxide (Al ₂o ₃) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, SYM-AL04, concentration 2.3 quality %] with heat treatment (burning till) can be utilized to obtain vanadium oxide (V ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, V-02, concentration 2 quality %] heat treatment (burning till) maybe can be utilized to obtain tantalum oxide (Ta ₂o ₅) commercially available organic metal film coated shaped material [(strain) high-purity chemical research institute, Ta-10-P, concentration 10 quality %] mixing, be prepared into passivating material (f2-1) ~ (f2-8) (with reference to table 11) as application type material.

In addition, the passivating material (f2-9) (with reference to table 11) being used alone aluminium oxide is prepared into.

Passivating material (f2-1) ~ (f2-9) is applied to respectively the one side of p-type silicon substrate in the same manner as reference example 2-1, afterwards it is heat-treated (burning till), make passivating film, use this passivating film to measure the voltage-dependent of static capacity, and calculate fixed charge density thus.

And then, passivating material (f2-1) ~ (f2-9) is applied to respectively the two sides of p-type silicon substrate in the same manner as reference example 2-1, and (burning till) is heat-treated to it and obtains sample, use the sample determination of gained carrier lifetime.The result of gained is summarized in table 11.

As shown in table 11, aluminium oxide/vanadium oxide in passivating material or tantalum oxide are 90/10 and 80/20, there is relatively large deviation in the value of fixed charge density, and cannot stably obtain negative fixed charge density, but can confirm and can realize negative fixed charge density by using aluminium oxide and niobium oxide.Visible: when using aluminium oxide/vanadium oxide or tantalum oxide are the passivating material of 90/10 and 80/20 and utilize CV method to measure, according to circumstances to become the passivating film showing positive fixed charge, therefore do not reach the negative fixed charge of stably display.In addition, the passivating film showing positive fixed charge can use as the passivating film of N-shaped silicon substrate.On the other hand, the passivating material (f2-9) that aluminium oxide reaches 100 quality % cannot obtain negative fixed charge density.

[table 11]

[reference example 2-10]

To use doped with the monocrystalline silicon substrate of boron as silicon substrate 101, be made into the solar cell device of structure shown in Fig. 8.After texture processing is carried out to the surface of silicon substrate 101, the phosphorus diffusion material of application type is only applied to sensitive surface side, and utilizes heat treatment to form diffusion layer 102 (phosphorus-diffused layer).Afterwards, diluted hydrofluoric acid is utilized to remove the phosphorus diffusion material of application type.

Then, utilize plasma CVD to form SiN film as sensitive surface antireflection film 103 in sensitive surface side.Then, ink-jet method is utilized to be applied to the region except contact area (peristome OA) of the rear side of silicon substrate 101 with reference to passivating material (a2-1) obtained in embodiment 2-1.Then, it is heat-treated, form the passivating film 107 with peristome OA.In addition, as passivating film 107, the sample using passivating material (c2-1) obtained in reference example 2-5 has also been made separately.

In addition, at this, the formation of the silver electrode about light, the burning describing not perforate in SiN film leads to operation, but in SiN film, etching also can be utilized in advance to wait formation peristome OA, forms silver electrode afterwards.

In order to compare, in above-mentioned production process, do not carry out the formation of passivating film 107, and whole of side printing Aluminum Paste overleaf, and form the p corresponding with BSF layer 104 at whole ⁺layer 114 and the electrode 116 of answering with the 2nd electrode pair, form the solar cell device of the structure of Fig. 5.Evaluating characteristics (short circuit current, open circuit voltage, Fill factor and conversion efficiency) has been carried out to these solar cell devices.Evaluating characteristics measures according to JIS-C-8913 (2005 year) and JIS-C-8914 (2005 year).The results are shown in table 12.

Shown by table 12, if will have the solar cell device of passivating film 107 compared with not having the solar cell device of passivating film 107, then short circuit current and open circuit voltage all increase, the maximum raising 0.6% of conversion efficiency (photoelectric conversion efficiency).

[table 12]

For the disclosure of No. 2012-160336th, Japanese patent application, No. 2012-218389, No. 2013-011934, No. 2013-040152 and No. 2013-040153, its entirety is incorporated in this specification.The whole documents recorded in this specification, patent application and technical standard, with specifically and describe respectively each document, patent application and technical standard situation with degree as with reference to quoting in this specification.

Claims

1. a solar cell device, it has:

Have sensitive surface, with the described back side of sensitive surface opposition side and the semiconductor substrate of side;

Be configured at the sensitive surface electrode on described sensitive surface;

Be configured at the backplate on the described back side; With

To be configured at least one face in described sensitive surface, the described back side and described side and containing being selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃and HfO ₂in the passivation layer of at least a kind of compound.

2. solar cell device according to claim 1, wherein, described passivation layer is also containing Al ₂o ₃.

3. solar cell device according to claim 1 and 2, wherein, described passivation layer is the heat treatment thing of passivation layer formation composition.

4. solar cell device according to claim 3, wherein, described passivation layer formation composition contains and is selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃, HfO ₂and at least a kind of compound in the compound shown in following general formula (I),

M(OR ¹) _m(I)

In formula (I), M comprises at least a kind of metallic element be selected from Nb, Ta, V, Y and Hf, R ¹separately represent the alkyl of carbon number 1 ~ 8 or the aryl of carbon number 6 ~ 14, m represents the integer of 0 ~ 5.

5. solar cell device according to claim 4, wherein, described passivation layer formation composition contains and is selected from Nb ₂o ₅and the M in described general formula (I) is at least a kind of niobium compound in the compound of Nb, total containing ratio of the described niobium compound in described passivation layer formation composition is with Nb ₂o ₅be scaled 0.1 quality % ~ 99.9 quality %.

6. the solar cell device according to any one of claim 3 ~ 5, wherein, described passivation layer formation composition is also containing being selected from Al ₂o ₃and at least a kind of aluminium compound in the compound shown in following general formula (II),

In formula (II), R ²separately represent the alkyl of carbon number 1 ~ 8, n represents the integer of 0 ~ 3, X ²and X ³separately represent oxygen atom or methylene, R ³, R ⁴and R ⁵separately represent the alkyl of hydrogen atom or carbon number 1 ~ 8.

7. solar cell device according to claim 6, wherein, the R in described general formula (II) ²it is separately the alkyl of carbon number 1 ~ 4.

8. the solar cell device according to claim 6 or 7, wherein, the n in described general formula (II) is integer, the R of 1 ~ 3 ⁵it is separately the alkyl of hydrogen atom or carbon number 1 ~ 4.

9. the solar cell device according to any one of claim 6 ~ 8, wherein, described passivation layer formation composition comprises and is selected from Al ₂o ₃and at least a kind of aluminium compound in the compound shown in described general formula (II), the containing ratio of the described aluminium compound in described passivation layer formation composition is 0.1 quality % ~ 80 quality %.

10. the solar cell device according to any one of claim 3 ~ 9, wherein, described passivation layer formation composition is also containing liquid medium.

11. solar cell devices according to claim 10, wherein, described liquid medium comprises at least a kind that is selected from hydrophobic organic solvent, non-proton organic solvent, terpene solvent, ester solvent, ether solvents and alcoholic solvent.

The manufacture method of the solar cell device according to any one of 12. 1 kinds of claims 1 ~ 11, it comprises:

The operation of backplate is formed in the face contrary with described sensitive surface of described semiconductor substrate and the back side;

Passivation layer formation composition is given at least one face in described sensitive surface, the described back side and side and forms the operation of composition layer, described passivation layer formation composition contains and is selected from Nb ₂o ₅, Ta ₂o ₅, V ₂o ₅, Y ₂o ₃, HfO ₂and at least a kind of compound in the compound shown in following general formula (I); With

Described composition layer is heat-treated and forms the operation of passivation layer,

M(OR ¹) _m(I)

The manufacture method of 13. solar cell devices according to claim 12, wherein, described passivation layer formation composition is also containing being selected from Al ₂o ₃and at least a kind of aluminium compound in the compound shown in following general formula (II),

The manufacture method of 14. solar cell devices according to claim 12 or 13, wherein, described heat treated temperature is more than 400 DEG C.

The manufacture method of 15. solar cell devices according to any one of claim 12 ~ 14, wherein, the operation of described formation composition layer comprises the step utilizing silk screen print method or ink-jet method to give described passivation layer formation composition.

16. 1 kinds of solar modules, its wiring material that there is the solar cell device according to any one of claim 1 ~ 11 and be configured on the electrode of described solar cell device.