WO2018021121A1

WO2018021121A1 - Impurity diffusion composition and semiconductor element production method using impurity diffusion composition

Info

Publication number: WO2018021121A1
Application number: PCT/JP2017/026150
Authority: WO
Inventors: 剛北田; 由洋池上; 新井　名奈
Original assignee: 東レ株式会社
Priority date: 2016-07-29
Filing date: 2017-07-19
Publication date: 2018-02-01
Also published as: TW201829625A; JPWO2018021121A1

Abstract

An impurity diffusion composition according to one embodiment is for diffusing a desired conductive impurity-diffused component into a semiconductor substrate. The impurity diffusion composition contains a polysiloxane (A) and an impurity-diffused component (B). The polysiloxane (A) contains a carboxyl group and/or a dicarboxylic acid anhydride structure. The impurity diffusion composition is for use in a semiconductor element production method and is particularly suitable for use in the production of solar cells.

Description

Impurity diffusion composition and method for manufacturing semiconductor device using the same

The present invention relates to an impurity diffusion composition for diffusing an impurity diffusion component in a semiconductor substrate, and a method for manufacturing a semiconductor element using the same.

Currently, in the manufacture of a semiconductor element such as a solar cell, when an n-type or p-type impurity diffusion layer is formed in a semiconductor substrate, an impurity diffusion source is formed on the semiconductor substrate, and thermal diffusion is performed in the semiconductor substrate. A method of diffusing impurity diffusion components is employed. The impurity diffusion source is formed by a CVD method or a solution coating method of a liquid impurity diffusion composition.

For example, when using a liquid impurity diffusion composition, a thermal oxide film is first formed on the surface of the semiconductor substrate, and then a resist having a predetermined pattern is laminated on the thermal oxide film by photolithography. Then, using the resist as a mask, the portion of the thermal oxide film not masked with the resist is etched with acid or alkali, and then the resist is removed to form a mask with the thermal oxide film. Subsequently, an n-type or p-type impurity diffusion composition is applied, and the impurity diffusion composition is adhered to the portion where the mask is opened. Thereafter, the impurity diffusion component in the composition is thermally diffused into the semiconductor substrate at 600 ° C. to 1250 ° C. to form an n-type or p-type impurity diffusion layer.

In recent years, with respect to the manufacture of such semiconductor elements such as solar cells, there has been a strong demand for a method of easily forming an impurity diffusion layer on a desired portion of a semiconductor substrate without using conventional and complicated photolithography technology. It is rare. As such a method, an impurity diffusion composition is applied on a semiconductor substrate, and this coating film (that is, the impurity diffusion composition film) is heated by partially irradiating a laser beam, and selectively. A method for forming an impurity diffusion layer has been studied (see, for example, Patent Documents 1 and 2).

JP 2012-114298 A JP 2009-238824 A

However, the conventional impurity diffusion composition is not irradiated with laser light when the impurity diffusion component is locally diffused from the impurity diffusion composition film into the semiconductor substrate using laser light or the like. As a result, there has been a problem in the cleanability of the dry film of the impurity diffusion composition remaining on the semiconductor substrate. The “dry film of the impurity diffusion composition” is a portion of the impurity diffusion composition film formed by coating on a semiconductor substrate that is not irradiated with laser light, that is, a portion not irradiated with laser.

The present invention has been made in view of the above circumstances, and has an excellent impurity diffusibility to a semiconductor substrate and cleans a dry film (a laser-irradiated portion) of the impurity diffusion composition remaining on the semiconductor substrate. An object of the present invention is to provide an impurity diffusion composition having excellent properties and a method for producing a semiconductor device using the same.

In order to solve the above problems and achieve the object, the impurity diffusion composition according to the present invention contains polysiloxane (A) and an impurity diffusion component (B), and the polysiloxane (A) It contains at least one of a carboxyl group and a dicarboxylic anhydride structure.

The impurity diffusion composition according to the present invention is characterized in that, in the above invention, the polysiloxane (A) is a polysiloxane represented by the following general formula (1).

(In the general formula (1), R ¹ represents a substituent containing at least one of a carboxyl group and a dicarboxylic anhydride structure, and a plurality of R ¹ may be the same or different from each other. R ² , R ³ and R ⁴ are a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an acyl group having 2 to 6 carbon atoms, or 6 to 6 carbon atoms Any one of 15 aryl groups, and a plurality of R ² , R ³ and R ⁴ may be the same or different from each other, n and m each represent a constituent ratio (%) of each component in parentheses; n + m = 100, and n: m = 5: 95 to 30:70.)

In the impurity diffusion composition according to the present invention, in the above invention, R ¹ in the general formula (1) includes a group represented by any one of the following general formulas (2) to (6). It is characterized by.

(In the general formulas (2) to (6), R ⁵ , R ⁷ , R ⁸ and R ⁹ represent a divalent organic group having 1 to 20 carbon atoms. R ⁶ represents a hydrogen atom or 1 to Represents an alkyl group of 3. R ¹⁰ , R ¹¹ and R ^{12 each} represents a single bond, a chain aliphatic hydrocarbon group having 1 to 10 carbon atoms, a cyclic aliphatic hydrocarbon group having 3 to 16 carbon atoms, or a carbon number Represents a 2-6 alkylcarbonyloxy group, a carbonyl group, an ether group, an ester group, an amide group, an aromatic group having 6 to 16 carbon atoms, or a divalent group having any one of these. The atom is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 16 carbon atoms, an alkylcarbonyloxy group having 2 to 6 carbon atoms, a hydroxy group, an amino group, a carboxyl group, or Optionally substituted with a thiol group, h, j, k and And l represents an integer of 0 to 3.)

The impurity diffusion composition according to the present invention is characterized in that, in the above invention, the content of the impurity diffusion component (B) is from 0.1% by mass to 20% by mass.

In the impurity diffusion composition according to the present invention, the impurity diffusion component (B) is phosphoric acid, diphosphorus pentoxide, polyphosphoric acid, phosphoric acid ester, boron oxide, boric acid, boric acid ester. 1 or more types selected from boronic acid and boronic acid ester.

In the impurity diffusion composition according to the present invention, in the above invention, the impurity diffusion component (B) contains one or more selected from boric acid, boronic acid, boric acid ester, and boronic acid ester, And water and a water-soluble binder.

The impurity diffusion composition according to the present invention is characterized in that, in the above invention, the water-soluble binder is polyvinyl alcohol.

In addition, a method for manufacturing a semiconductor device according to the present invention includes a film forming step of forming an impurity diffusion composition film by applying the impurity diffusion composition according to any of the above inventions on a semiconductor substrate, and the impurity And a layer forming step of diffusing an impurity diffusion component from the diffusion composition film into the semiconductor substrate to form an impurity diffusion layer.

In addition, a method for manufacturing a semiconductor device according to the present invention includes a film forming step of forming an impurity diffusion composition film by applying the impurity diffusion composition according to any of the above inventions on a semiconductor substrate, and the impurity And a layer forming step of irradiating the diffusion composition film with laser light to diffuse an impurity diffusion component from the impurity diffusion composition film into the semiconductor substrate to form an impurity diffusion layer.

In addition, a method for manufacturing a semiconductor device according to the present invention includes a film forming step of forming an impurity diffusion composition film by applying the impurity diffusion composition according to any of the above inventions on a semiconductor substrate, and the impurity A layer forming step of irradiating a part of the diffusion composition film with laser light to diffuse an impurity diffusion component from the part of the impurity diffusion composition film into the semiconductor substrate to form an impurity diffusion layer; and the impurity diffusion composition And a removal step of removing, by an acid or an alkali, an unirradiated portion of the material film that has not been irradiated with the laser beam.

ADVANTAGE OF THE INVENTION According to this invention, the impurity diffusion composition which has the outstanding impurity diffusivity to a semiconductor substrate, and was excellent in the cleaning property of the dry film of the impurity diffusion composition which remain | survives in a semiconductor substrate, and a semiconductor element using the same The production method can be provided.

FIG. 1A is a diagram illustrating an example of a method for manufacturing a semiconductor device according to an embodiment of the present invention. FIG. 1B is a diagram showing an example of a method for manufacturing a solar cell using a semiconductor element according to an embodiment of the present invention.

Hereinafter, preferred embodiments of an impurity diffusion composition according to the present invention and a semiconductor device manufacturing method using the same will be described in detail with reference to the drawings as necessary. Note that the present invention is not limited to these embodiments.

The impurity diffusion composition according to the present invention is a composition for forming an impurity diffusion layer of a desired conductivity type (n-type, p-type) on a semiconductor substrate when manufacturing a semiconductor element such as a solar cell, Polysiloxane (A) and an impurity diffusion component (B) are contained. In this impurity diffusion composition, polysiloxane (A) contains at least one of a carboxyl group and a dicarboxylic anhydride structure. Hereinafter, each component contained in the impurity diffusion composition according to the present invention will be described in detail.

(Polysiloxane (A))
The polysiloxane (A) in the present invention is a polysiloxane containing at least one of a carboxyl group and a dicarboxylic anhydride structure. By having such a configuration, the polysiloxane (A) can impart excellent impurity diffusibility to the semiconductor substrate when contained in the impurity diffusion composition. In addition, the polysiloxane (A) can improve the detergency of the dry film of the impurity diffusion composition remaining on the semiconductor substrate after the diffusion of the impurity diffusion component into the semiconductor substrate with an acid or alkali.

The polysiloxane (A) contains at least one of a carboxyl group and a dicarboxylic acid anhydride structure, so that at least one of the carboxyl group and the dicarboxylic acid anhydride structure in the polysiloxane (A) is acidic or alkaline. Affinity with the cleaning solution is improved. That is, when the dry film of the impurity diffusion composition containing the polysiloxane (A) in the present invention is cleaned, the solubility of the dry film in the cleaning liquid is improved by the polysiloxane (A). The detergency of the dry film can be improved.

As described above, the polysiloxane (A) containing at least one of a carboxyl group and a dicarboxylic anhydride structure is preferably a polysiloxane represented by the following general formula (1).

In the general formula (1), R ¹ represents a substituent containing at least one of a carboxyl group and a dicarboxylic anhydride structure. The plurality of R ¹ may be the same or different. R ² , R ³ and R ⁴ are a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an acyl group having 2 to 6 carbon atoms, or a carbon number Represents any of 6 to 15 aryl groups; A plurality of R ² , R ³ and R ⁴ may be the same or different. n and m show the component ratio (%) of the component in each parenthesis. These n and m are n + m = 100, and n: m = 5: 95 to 30:70.

These n and m are “n: m = 5: 95 to 30:70” means that the content ratio of the component derived from the organosilane having a carboxyl group in the polysiloxane (A) is derived from the organosilane. This means that the Si atom mole ratio relative to the number of moles of Si atoms in the entire polysiloxane (A) is 5 mol% or more and 30 mol% or less.

When n is 5 or more, the detergency of the dry film of the impurity diffusion composition by acid or alkali can be improved. As a result, the cleaning process for removing the dry film of the impurity diffusion composition from the semiconductor substrate can be performed in a shorter time. Moreover, when n is 30 or less, the impurity diffusibility from the impurity diffusion composition film to the semiconductor substrate can be improved. The polysiloxane (A) represented by the general formula (1) may be a block copolymer or a random copolymer.

The content of the carboxyl group in the polysiloxane (A) is measured, for example, by measuring the ²⁹ Si-NMR spectrum of the polysiloxane (A), and the peak area of the Si atom to which the carboxyl group is bonded and the carboxyl group is not bonded. It can obtain | require from ratio with the peak area of Si atom. Further, when the Si atom and the carboxyl group are not directly bonded, the polysiloxane (A) is obtained from the integration ratio between the peak derived from the carboxyl group and the other peaks excluding the silanol group using ¹ H-NMR spectrum. It is possible to calculate the content of carboxyl groups indirectly bonded to Si atoms by calculating the total content of carboxyl groups and combining this calculation result with the results of the ²⁹ Si-NMR spectrum described above. it can.

The content of the dicarboxylic acid anhydride structure in the polysiloxane (A) can be determined by, for example, measuring the ²⁹ Si-NMR spectrum of the polysiloxane (A), the peak area of the Si atom bonded with the dicarboxylic acid anhydride structure, and the dicarboxylic acid anhydride structure. It can be determined from the ratio to the peak area of Si atoms to which the acid anhydride structure is not bonded. In addition, when the Si atom and the dicarboxylic acid anhydride structure are not directly bonded, the integral ratio between the peak derived from the dicarboxylic acid anhydride structure and the other peaks excluding the silanol group is determined using the ¹ H-NMR spectrum. Then, the content of dicarboxylic acid anhydride structure in the whole polysiloxane (A) is calculated, and the result of this calculation and the result of the ²⁹ Si-NMR spectrum described above are combined to obtain the dicarboxylic acid indirectly bonded to the Si atom. The content of the acid anhydride structure can be calculated.

In particular, R ¹ in the general formula (1) preferably contains a group represented by any one of the following general formulas (2) to (6). Thereby, the better washing | cleaning property by the acid or alkali of the dry film | membrane of the said impurity diffusion composition is obtained.

In the general formulas (2) to (6), R ⁵ , R ⁷ , R ⁸ and R ⁹ represent a divalent organic group having 1 to 20 carbon atoms. R ⁶ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ¹⁰ , R ¹¹ and R ¹² are each a single bond, a chain aliphatic hydrocarbon group having 1 to 10 carbon atoms, a cyclic aliphatic hydrocarbon group having 3 to 16 carbon atoms, or an alkylcarbonyloxy group having 2 to 6 carbon atoms. A group, a carbonyl group, an ether group, an ester group, an amide group, an aromatic group having 6 to 16 carbon atoms, or a divalent group having any one of them. The hydrogen atoms of these groups are alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, aryl groups having 6 to 16 carbon atoms, alkylcarbonyloxy groups having 2 to 6 carbon atoms, hydroxy groups, amino groups It may be substituted with a group, a carboxyl group or a thiol group. h, j, k, and l represent an integer of 0 to 3.

Next, the organosilane compound containing at least one of a carboxyl group and a dicarboxylic anhydride structure will be specifically described. This organosilane compound is a raw material of polysiloxane (A) containing at least one of a carboxyl group and a dicarboxylic anhydride structure. The polysiloxane (A) represented by the general formula (1) can be obtained by appropriately selecting and hydrolyzing and condensing an organosilane compound described below.

Examples of the organosilane compound having a carboxyl group include a urea group-containing organosilane compound represented by the following general formula (7) or a urethane group-containing organosilane compound represented by the following general formula (8). Can be mentioned. As the organosilane compound having a carboxyl group, two or more of these may be used.

In the general formulas (7) and (8), R ¹³ , R ¹⁵ and R ¹⁹ represent a divalent organic group having 1 to 20 carbon atoms. R ¹⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ¹⁶ , R ¹⁷ and R ¹⁸ are each an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an acyl group having 2 to 6 carbon atoms, Represents any of 15 aryl groups. R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different. However, at least one of R ¹⁶ , R ¹⁷ and R ¹⁸ is an alkoxy group having 1 to 6 carbon atoms.

Preferred examples of R ¹³ and R ¹⁹ in the general formulas (7) and (8) include a methylene group, an ethylene group, an n-propylene group, an n-butylene group, a phenylene group, —CH ₂ —C ₆ H ₄ —CH. Examples thereof include hydrocarbon groups such as ₂ — and —CH ₂ —C ₆ H ₄ —. Among these, from the viewpoint of heat resistance, carbon atoms having an aromatic ring such as a phenylene group, —CH ₂ —C ₆ H ₄ —CH ₂ —, —CH ₂ —C ₆ H ₄ — as R ¹³ and R ¹⁹ A hydrogen group is preferred.

R ¹⁴ in the general formula (7) is preferably hydrogen or a methyl group from the viewpoint of reactivity. Specific examples of R ¹⁵ in the general formulas (7) and (8) include hydrocarbon groups such as a methylene group, an ethylene group, an n-propylene group, an n-butylene group and an n-pentylene group, and an oxymethylene group. Oxyethylene group, oxy n-propylene group, oxy n-butylene group, oxy n-pentylene group and the like. Among these, from the viewpoint of ease of synthesis, R ^{15 represents} methylene group, ethylene group, n-propylene group, n-butylene group, oxymethylene group, oxyethylene group, oxy n-propylene group, oxy n-butylene. Groups are preferred.

Of R ¹⁶ , R ¹⁷ and R ^{18 in} the general formulas (7) and (8), specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group and an isopropyl group. Among these, a methyl group or an ethyl group is preferable as the alkyl group for R ¹⁶ , R ¹⁷ and R ¹⁸ from the viewpoint of ease of synthesis. Of these R ¹⁶ , R ¹⁷ and R ¹⁸ , specific examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, and an isopropoxy group. Among these, a methoxy group or an ethoxy group is preferable as the alkoxy group for R ¹⁶ , R ^17, and R ¹⁸ from the viewpoint of ease of synthesis. In addition, examples of the substituent of the substituent of R ¹⁶ , R ¹⁷ and R ¹⁸ include a methoxy group and an ethoxy group. Specific examples include a 1-methoxypropyl group and a methoxyethoxy group.

The urea group-containing organosilane compound represented by the general formula (7) includes an aminocarboxylic acid compound represented by the following general formula (9) and an isocyanate group-containing organosilane represented by the following general formula (11). It can be obtained from a compound by a known urea formation reaction. Further, the urethane group-containing organosilane compound represented by the general formula (8) includes a hydroxycarboxylic acid compound represented by the following general formula (10) and an isocyanate group-containing compound represented by the following general formula (11). It can be obtained from an organosilane compound by a known urethanization reaction.

In the general formulas (9) to (11), R ¹³ , R ¹⁵ and R ¹⁹ represent a divalent organic group having 1 to 20 carbon atoms. R ¹⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ¹⁶ , R ¹⁷ and R ¹⁸ are each an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an acyl group having 2 to 6 carbon atoms, Represents any of 15 aryl groups. Preferred examples of these R ¹³ ~ R ¹⁹ of the general formula (7) is as described above for R ¹³ ~ R ¹⁹ in (8).

Other specific examples of the organosilane compound having a carboxyl group include a compound represented by the general formula (12).

In the general formula (12), R ²⁰ represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an acyl group having 2 to 6 carbon atoms, or 6 carbon atoms. Represents any of ˜15 aryl groups. The plurality of R ²⁰ may be the same or different. q represents an integer of 1 to 3. r represents an integer of 2 to 20.

Specific examples of the organosilane compound having a dicarboxylic acid anhydride structure include organosilane compounds represented by any one of the following general formulas (13) to (15). As an organosilane compound having a dicarboxylic acid anhydride structure, two or more of these may be used.

In the general formulas (13) to (15), R ²² , R ²³ and R ²⁴ are each an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, It represents either an acyl group having 2 to 6 or an aryl group having 6 to 15 carbon atoms. However, at least one of R ²² , R ²³ and R ²⁴ is an alkoxy group having 1 to 6 carbon atoms.

R ²¹ , R ²⁵ and R ²⁶ are each a single bond or a chain aliphatic hydrocarbon group having 1 to 10 carbon atoms, a cyclic aliphatic hydrocarbon group having 3 to 16 carbon atoms, or an alkylcarbonyloxy group having 2 to 6 carbon atoms. A group, a carbonyl group, an ether group, an ester group, an amide group, an aromatic group having 6 to 16 carbon atoms, or a divalent group having any one of them. The hydrogen atoms of these groups are alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, aryl groups having 6 to 16 carbon atoms, alkylcarbonyloxy groups having 2 to 6 carbon atoms, hydroxy groups, amino groups It may be substituted with a group, a carboxyl group or a thiol group. h, j, k, and l represent an integer of 0 to 3.

Specific examples of R ²¹ , R ²⁵ and R ²⁶ include —C ₂ H ₄ —, —C ₃ H ₆ —, —C ₄ H ₈ —, —O—, —C ₃ H ₆ OCH ₂ CH (OH). Examples thereof include CH ₂ O ₂ C—, —CO—, —CO ₂ —, —CONH—, and organic groups listed below.

Specific examples of the organosilane compound represented by the general formula (13) include 3-trimethoxysilylpropyl succinic anhydride, 3-triethoxysilylpropyl succinic anhydride, 3-triphenoxysilylpropyl succinic anhydride. Etc. Specific examples of the organosilane compound represented by the general formula (14) include 3-trimethoxysilylsilylpropylcyclohexyl dicarboxylic acid anhydride. Specific examples of the organosilane compound represented by the general formula (15) include 3-trimethoxysilylsilylpropylphthalic anhydride.

As a raw material for the polysiloxane (A) containing at least one of a carboxyl group and a dicarboxylic anhydride structure, an organosilane compound other than an organosilane compound containing at least one of a carboxyl group and a dicarboxylic anhydride structure is used in combination. It is also possible.

Examples of such organosilane compounds include tetrafunctional silane, trifunctional silane, bifunctional silane, and monofunctional silane. Examples of the tetrafunctional silane include tetramethoxysilane, tetraethoxysilane, tetraacetoxysilane, and tetraphenoxysilane. Examples of trifunctional silanes include methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltrin-butoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltrin-butoxy. Silane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, decyltrimethoxysilane, vinyl Trimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, pheny Trimethoxysilane, phenyltriethoxysilane, p-hydroxyphenyltrimethoxysilane, 1- (p-hydroxyphenyl) ethyltrimethoxysilane, 2- (p-hydroxyphenyl) ethyltrimethoxysilane, 4-hydroxy-5- ( p-hydroxyphenylcarbonyloxy) pentyltrimethoxysilane, trifluoromethyltrimethoxysilane, trifluoromethyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-amino Propyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-ethylene Xylcyclohexyl) ethyltriethoxysilane, [(3-ethyl-3-oxetanyl) methoxy] propyltrimethoxysilane, [(3-ethyl-3-oxetanyl) methoxy] propyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 1-naphthyltrimethoxysilane, 1-naphthyltriethoxysilane, 1-naphthyltrimethoxy-n-propoxysilane, 2-naphthyltrimethoxysilane, 1-anthracenyltrimethoxysilane, 9-anthracenyltrimethoxysilane, 9-phenant Examples include lenyltrimethoxysilane, 9-fluorenyltrimethoxysilane, 2-fluorenyltrimethoxysilane, 1-pyrenyltrimethoxysilane, 2-indenyltrimethoxysilane, and 5-acenaphthenyltrimethoxysilane. I can get lost. Examples of the bifunctional silane include dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldiacetoxysilane, di-n-butyldimethoxysilane, diphenyldimethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, (3-glycidide) And xylpropyl) methyldiethoxysilane, di (1-naphthyl) dimethoxysilane, and di (1-naphthyl) diethoxysilane. Examples of monofunctional silanes include trimethylmethoxysilane, tri-n-butylethoxysilane, (3-glycidoxypropyl) dimethylmethoxysilane, and (3-glycidoxypropyl) dimethylethoxysilane. Two or more of these organosilanes may be used.

The production method of polysiloxane (A) containing at least one of a carboxyl group and a dicarboxylic anhydride structure is not particularly limited, and a known method such as partial condensation of an organosilane compound can be used. . Examples of this production method include a method of adding a reaction solvent, water and, if necessary, a catalyst to an organosilane mixture and heating and stirring at 50 to 150 ° C. for about 0.5 to 100 hours. In this production method, during the heating and stirring, if necessary, hydrolysis by-products (alcohols such as methanol) and condensation by-products (water) may be distilled off by distillation. Here, the partial condensation means that Si—OH remains in a part of the resulting polysiloxane (A) rather than condensing all of the hydrolyzed Si—OH. In general condensation conditions described later, Si—OH is generally partially left, and in the present invention, the amount of Si—OH to be left is not limited.

The reaction solvent is not particularly limited, but usually the same solvent as described below can be used. The addition amount of such a reaction solvent is preferably 10 parts by weight or more and 1500 parts by weight or less with respect to 100 parts by weight of a monomer such as organosilane. Moreover, it is preferable that the addition amount of the water used for a hydrolysis reaction is 0.5 mol or more and 5 mol or less with respect to 1 mol of a hydrolysable group.

The catalyst added as necessary is not particularly limited, but an acid catalyst is preferably used. Specific examples of the acid catalyst include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, phosphoric acid, acetic acid, trifluoroacetic acid, formic acid, polyvalent carboxylic acid or anhydride thereof, and ion exchange resin. The addition amount of such a catalyst is preferably 0.01 parts by weight or more and 10 parts by weight or less with respect to 100 parts by weight of a monomer such as organosilane.

Further, from the viewpoint of storage stability of the impurity diffusion composition, the catalyst can be removed from the polysiloxane solution after hydrolysis and partial condensation as necessary. Although there is no restriction | limiting in particular as this catalyst removal method, From the viewpoint of the ease of operation and a removability, what performs at least one of water washing and the process by ion exchange resin is preferable. The water washing is a method of diluting a polysiloxane solution with a suitable hydrophobic solvent and then concentrating the organic layer obtained by washing several times with water with an evaporator or the like. The treatment with an ion exchange resin is a method in which a polysiloxane solution is brought into contact with an appropriate ion exchange resin.

The content of the polysiloxane (A) containing at least one of a carboxyl group and a dicarboxylic anhydride structure in the impurity diffusion composition in the present invention is 0.1% by mass or more and 90% by mass in the impurity diffusion composition. % Or less, more preferably 0.1% by mass or more and 50% by mass or less. When the content of the polysiloxane (A) is within the above range, excellent impurity diffusibility and cleanability of the impurity diffusion composition can be obtained.

In the “group” in the present invention, “carbon number” represents the total number of carbon atoms including a group further substituted on the group. For example, an alkyl group having 1 to 10 carbon atoms means that the total number of carbon atoms in the alkyl group (including the substituent, if any) is 1 or more and 10 or less.

(Impurity diffusion component (B))
The impurity diffusion component (B) is a component for forming an impurity diffusion layer of a desired conductivity type (n-type or p-type) in the semiconductor substrate. The impurity diffusion component (B) is preferably a compound containing a Group 13 or Group 15 element. As the group 13 element, boron, aluminum and gallium are preferable, and boron is particularly preferable. As the group 15 element, phosphorus, arsenic, antimony and bismuth are preferable, and phosphorus is particularly preferable.

Examples of phosphorus compounds include phosphate esters and phosphites. Examples of phosphate esters include diphosphorus pentoxide, phosphoric acid, polyphosphoric acid, methyl phosphate, dimethyl phosphate, trimethyl phosphate, ethyl phosphate, diethyl phosphate, triethyl phosphate, propyl phosphate, and dipropyl phosphate. , Tripropyl phosphate, butyl phosphate, dibutyl phosphate, tributyl phosphate, phenyl phosphate, diphenyl phosphate, triphenyl phosphate, and the like. Examples of the phosphite ester include methyl phosphite, dimethyl phosphite, trimethyl phosphite, ethyl phosphite, diethyl phosphite, triethyl phosphite, propyl phosphite, dipropyl phosphite, Examples include tripropyl phosphate, butyl phosphite, dibutyl phosphite, tributyl phosphite, phenyl phosphite, diphenyl phosphite, triphenyl phosphite and the like. Of these, phosphoric acid, diphosphorus pentoxide or polyphosphoric acid is preferable from the viewpoint of doping.

Examples of the boron compound include boric acids, borates, halides, boronic acids, boric acid esters, and boronic acid esters. Specifically, examples of boric acids include boric acid and boron oxide. Examples of borates include ammonium borate. Examples of the halide include boron trifluoride, boron trichloride, boron tribromide, boron triiodide and the like. Examples of boronic acids include methyl boronic acid and phenyl boronic acid. Examples of borate esters include trimethyl borate, triethyl borate, tripropyl borate, tributyl borate, trioctyl borate, triphenyl borate, and the like. Examples of boronic acid esters include 2-phenyl-1,3,2-dioxaborinane and diisopropylmethylborane. Among these, from the viewpoint of diffusibility, boric acids, boronic acids, boric acid esters, and boronic acid esters are preferable.

The content of the impurity diffusion component (B) in the impurity diffusion composition according to the present invention can be arbitrarily determined according to the resistance value required for the semiconductor substrate, and is 0.01% by mass or more and 50% by mass or less. Is preferable, and it is more preferable that it is 0.1 mass% or more and 20 mass% or less. When the content of the impurity diffusion component (B) is within the above range, sufficient diffusibility of the impurity diffusion component (B) with respect to the semiconductor substrate can be obtained.

Further, when a boron compound is used as the impurity diffusion component (B), the impurity diffusion component (B) preferably contains a binder resin. In particular, the impurity diffusion component (B) preferably contains at least one selected from boric acid, boronic acid, boric acid ester and boronic acid ester, and further contains water and a water-soluble binder. . Here, the water-soluble binder refers to a binder having a solubility of 10% by weight or more with respect to water at 25 ° C.

Specifically, examples of the binder resin such as the above water-soluble binder include the following. For example, polyvinyl alcohol, polyvinyl acetal, polyvinyl butyral, polyacrylamide resin, polyvinyl pyrrolidone resin, polyethylene oxide resin, acrylamide alkyl sulfone resin, cellulose derivative, gelatin, gelatin derivative, starch, starch derivative, sodium alginate compound, xanthan, guar gum, guar gum Derivatives, scleroglucan, scleroglucan derivatives, tragacanth, tragacanth derivatives, dextrin, dextrin derivatives, water-soluble (meth) acrylate resins, water-soluble polybutadiene resins, water-soluble styrene resins, butyral resins, copolymers thereof Is mentioned. However, the binder resin in the impurity diffusion component (B) is not limited to these. The above “(meth) acrylic acid” means “acrylic acid or methacrylic acid”.

In the impurity diffusion component (B), the binder resin can be used alone or in combination of two or more. In particular, when the impurity diffusion component (B) is a boron compound, the binder resin has a 1,2-diol structure or 1,3-diol from the viewpoint of the formation of a complex with the boron compound and the stability of the formed complex. Those having a structure are preferable, and polyvinyl alcohol is particularly preferable.

Further, the polymerization degree of the binder resin in the impurity diffusion component (B) is not particularly limited, but a preferable polymerization degree range is 1000 or less, and particularly preferably 800 or less. As a result, excellent solubility of a hydroxyl group-containing polymer such as polyvinyl alcohol in an organic solvent is exhibited. On the other hand, the lower limit of the degree of polymerization is not particularly limited, but is preferably 100 or more from the viewpoint of easy handling of the binder resin. In the present invention, the degree of polymerization of the binder resin is determined as the number average degree of polymerization in terms of polystyrene in GPC (gel permeation chromatography) analysis.

(solvent)
The impurity diffusion composition according to the present invention preferably contains a solvent. This solvent can be used without particular limitation, but is appropriately selected depending on a coating method such as a spin coating method, an ink jet method, a screen printing method or a roll coating printing method. Examples of such solvents include ketone solvents, ether solvents, ester solvents, ether acetate solvents, aprotic polar solvents, alcohol solvents, glycol monoether solvents, terpene solvents, water, and the like. . One of these may be used alone, or two or more of these may be used in combination.

Examples of ketone solvents include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-iso-propyl ketone, methyl-n-butyl ketone, methyl-iso-butyl ketone, methyl-n-pentyl ketone, and methyl-n-hexyl. Ketone, diethyl ketone, dipropyl ketone, di-iso-butyl ketone, trimethylnonanone, cyclohexanone, cyclopentanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, γ-butyrolactone, γ-valerolactone, etc. It is done.

Examples of ether solvents include diethyl ether, methyl ethyl ether, methyl-n-propyl ether, di-iso-propyl ether, tetrahydrofuran, methyltetrahydrofuran, dioxane, dimethyldioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol Di-n-propyl ether, ethylene glycol dibutyl 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 di-n-propyl ether, diethylene glycol di- n-Butyl Ete , Diethylene glycol methyl-n-hexyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol methyl ethyl ether, triethylene glycol methyl n-butyl ether, triethylene glycol di-n-butyl ether, triethylene glycol methyl n-hexyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetradiethylene glycol methyl ethyl ether, tetraethylene glycol methyl-n-butyl ether, diethylene glycol di-n-butyl ether, tetraethylene glycol methyl-n-hexyl ether, tetraethylene Glycol di-n-butyl ether, propylene Recall dimethyl ether, propylene glycol diethyl ether, propylene glycol di-n-propyl ether, propylene glycol dibutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol methyl ethyl ether, dipropylene glycol methyl n-butyl ether, di Propylene glycol di-n-propyl ether, dipropylene glycol di-n-butyl ether, dipropylene glycol methyl-n-hexyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, tripropylene glycol methyl ethyl ether, tripropylene glycol methyl -N-butyl ether, tripropylene rubber Recall di-n-butyl ether, tripropylene glycol methyl-n-hexyl ether, tetrapropylene glycol dimethyl ether, tetrapropylene glycol diethyl ether, tetradipropylene glycol methyl ethyl ether, tetrapropylene glycol methyl-n-butyl ether, dipropylene glycol di-n -Butyl ether, tetrapropylene glycol methyl-n-hexyl ether, tetrapropylene glycol di-n-butyl ether and the like.

Examples of ester solvents include methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, and acetic acid. 3-methoxybutyl, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, 2- (2-butoxyethoxy) ethyl acetate, benzyl acetate, cyclohexyl acetate, methyl cyclohexyl acetate, nonyl acetate, methyl acetoacetate, ethyl acetoacetate , Diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, diacetic acid glyco Methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate Etc.

Examples of ether acetate solvents include ethylene glycol methyl ether propionate, ethylene glycol ethyl ether propionate, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, diethylene glycol methyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol-n. -Butyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, dipropylene glycol methyl ether acetate, dipropylene glycol ethyl ether acetate and the like.

Examples of the aprotic polar solvent include acetonitrile, N-methylpyrrolidinone, N-ethylpyrrolidinone, N-propylpyrrolidinone, N-butylpyrrolidinone, N-hexylpyrrolidinone, N-cyclohexylpyrrolidinone, N, N-dimethylformamide, N , N-dimethylacetamide, N, N-dimethylsulfoxide and the like.

Examples of alcohol solvents include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, i-pentanol, and 2-methylbutanol. , Sec-pentanol, t-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, n-octanol, 2-ethylhexanol, sec- Octanol, n-nonyl alcohol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, phenol, cyclohexanol, methylcyclohex Nord, benzyl alcohol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol.

Examples of the glycol monoether solvent include ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol mono-n-hexyl ether, Examples include ethoxy triglycol, tetraethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and tripropylene glycol monomethyl ether.

Examples of the terpene solvent include α-terpinene, α-terpineol, myrcene, alloocimene, limonene, dipentene, α-pinene, β-pinene, terpineol, carvone, osymene, and ferrandolene.

The content of the solvent in the impurity diffusion composition according to the present invention can be arbitrarily determined according to the viscosity of the impurity diffusion composition, but is preferably in the range of 1% by mass to 90% by mass.

(Surfactant)
The impurity diffusion composition according to the present invention may contain a surfactant. When the impurity diffusion composition contains a surfactant, uneven coating when the impurity diffusion composition is applied to the semiconductor substrate is improved, and as a result, a uniform coating film of the impurity diffusion composition film is obtained. As the surfactant, a fluorine-based surfactant or a silicone-based surfactant is preferably used.

Specific examples of the fluorosurfactant include a fluorosurfactant composed of a compound having a fluoroalkyl or fluoroalkylene group in at least one of the terminal, main chain and side chain. Examples of such a fluorosurfactant include 1,1,2,2-tetrafluorooctyl (1,1,2,2-tetrafluoropropyl) ether, 1,1,2,2-tetrafluorooctyl. Hexyl ether, octaethylene glycol di (1,1,2,2-tetrafluorobutyl) ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoropentyl) ether, octapropylene glycol di (1 , 1,2,2-tetrafluorobutyl) ether, hexapropylene glycol di (1,1,2,2,3,3-hexafluoropentyl) ether, sodium perfluorododecylsulfonate, 1,1,2,2 , 8,8,9,9,10,10-decafluorododecane, 1,1,2,2,3,3-hexafluorode N- [3- (perfluorooctanesulfonamido) propyl] -N, N'-dimethyl-N-carboxymethyleneammonium betaine, perfluoroalkylsulfonamidopropyltrimethylammonium salt, perfluoroalkyl-N-ethylsulfonylglycine Salt, bis (N-perfluorooctylsulfonyl-N-ethylaminoethyl) phosphate, monoperfluoroalkylethyl phosphate, and the like.

In addition, commercially available products include MegaFuck F142D, F172, F173, F183, F183, F444, F475, F477 (above, manufactured by Dainippon Ink & Chemicals, Inc.), Ftop EF301, 303, 352 ( Shin-Akita Kasei), Florard FC-430, FC-431 (Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC- 104, SC-105, SC-106 (Asahi Glass Co., Ltd.), BM-1000, BM-1100 (Yusho Co., Ltd.), NBX-15, FTX-218, DFX-218 (Neos Co.) There is a surfactant.

Examples of commercially available silicone surfactants include, for example, SH28PA, SH7PA, SH21PA, SH30PA, ST94PA (all manufactured by Toray Dow Corning Silicone), BYK067A, BYK310, BYK322, BYK331, BYK333, BYK355 (BIC Chemie Japan) Etc.).

When a surfactant is added to the impurity diffusion composition, the content of the surfactant in the impurity diffusion composition is preferably 0.0001 mass% or more and 1 mass% or less. By setting the content of the surfactant within the above range, excellent application properties of the impurity diffusion composition to the semiconductor substrate can be obtained.

(Thickener)
The impurity diffusion composition according to the present invention may contain a thickener for viscosity adjustment. Examples of the thickener include organic type and inorganic type. Examples of organic thickeners include cellulose, cellulose derivatives, starch, starch derivatives, polyvinyl pyrrolidone, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyurethane resins, polyurea resins, polyimide resins, polyamide resins, epoxy resins, polystyrene. Resin, polyester resin, synthetic rubber, natural rubber, polyacrylic acid, various acrylic resins, polyethylene glycol, polyethylene oxide, polypropylene glycol, polypropylene oxide, silicone oil, sodium alginate, xanthan gum polysaccharide, gellan gum polysaccharide, guar gum Polysaccharides, carrageenan polysaccharides, locust bean gum polysaccharides, carboxyvinyl polymers, hydrogenated castor oil, hydrogenated castor oil and fatty acid flax A mixture with a wax, a special fatty acid, a polyethylene oxide, a mixture of a polyethylene oxide and an amide, a fatty acid polyvalent carboxylic acid, a phosphate ester surfactant, a salt of a long-chain polyaminoamide and phosphoric acid, Specially modified polyamide system is exemplified. Inorganic thickeners include, for example, bentonite, montmorillonite, magnesia montmorillonite, tetsu montmorillonite, tectum magnesia montmorillonite, beidellite, aluminiderite, sapphire, aluminian support stone, laponite, Examples thereof include aluminum silicate, aluminum magnesium silicate, organic hectorite, fine particle silicon oxide, colloidal alumina, and calcium carbonate. You may use these in combination of multiple types.

Among these thickeners, thixotropic agents that impart thixotropic properties include cellulose, cellulose derivatives, sodium alginate, xanthan gum polysaccharides, gellan gum polysaccharides, guar gum polysaccharides, carrageenan polysaccharides, locust beans. Gum-based polysaccharide, carboxyvinyl polymer, hydrogenated castor oil, hydrogenated castor oil and fatty acid amide wax, special fatty acid, polyethylene oxide, polyethylene oxide and amide, fatty acid polyvalent carboxyl Acid, phosphate ester surfactant, salt of long-chain polyaminoamide and phosphoric acid, specially modified polyamide, bentonite, montmorillonite, magnesia montmorillonite, tetsumonmorillonite, tetsumagnesium montmorillonite, beidellite , Almin Baiderai , It can be exemplified supported stone, Arumini Ann support stone, laponite, aluminum silicate, aluminum magnesium silicate, organic hectorite, particulate silicon oxide, colloidal alumina, and calcium carbonate.

Moreover, as a commercial item of a cellulose thickener, there exist 11110, 1120, 1130, 1140, 1150, 1160, 1170, 1180, 1190, 2200, 2260, 2280, 2450, etc. by Daicel Finechem. Commercially available polysaccharide thickeners include Viscalin PC209, Viscarin PC389, SeaKemXP8012, manufactured by FM Chemicals, CAM-H, GJ-182, SV-300, LS-20, LS-30, manufactured by Mitsubishi Corporation. XGT, XGK-D, G-100, LG-10 and the like.

Commercially available products of hydrogenated castor oil thickener include Disparon 308 and NAMLONT-206 manufactured by Enomoto Kasei Co., Ltd., and T-20SF and T-75F manufactured by Ito Oil Co., Ltd. Commercially available products of polyethylene oxide thickeners include D-10A, D-120, D-120-10, D-1100, DS-525, DS-313 manufactured by Ito Oil Co., Ltd., and Disparon 4200 manufactured by Enomoto Kasei Co., Ltd. -20, PF-911, PF-930, 4401-25X, NS-30, NS-5010, NS-5025, NS-5810, NS-5210, NS-5310, NS-5310, Kyoeisha Chemical There are Flownon SA-300 and SA-300H manufactured by the same company. Commercially available amide type thickeners include T-250F, T-550F, T-850F, T-1700, T-1800, T-2000 manufactured by Ito Oil Co., Ltd., Dispalon 6500, 6300 manufactured by Enomoto Kasei Co., Ltd. , 6650, 6700, 3900EF, Tallen 7200, 7500, 8200, 8300, 8700, 8900, KY-2000, KU-700, M-1020, VA manufactured by Kyoeisha Chemical Co., Ltd. -780, VA-750B, 2450, Flownon SD-700, SDR-80, etc.

Commercially available products of bentonite-based thickener include Hojun's Bengel, Bengel HV, HVP, F, FW, Bright 11, A, W-100, W-100U, W-300U. SH, Multiven, Esben, Esben C, E, W, P, WX, Organite, Organite D, and the like. As commercial products of fine particle silicon oxide-based thickeners, Nippon Aerosil Co., Ltd. AEROSILR972, R974, NY50, RY200S, RY200, RX50, NAX50, RX200, RX300, VPNKC130, R805, R104, R711, OX50, 50, 90G, 130, 200, 300, 380, WACKER HDK S13, V15, N20, N20P, T30, T40, manufactured by Asahi Kasei Corporation H15, H18, H20, H30, etc.

As the thickener, polyethylene glycol, polyethylene oxide, polypropylene glycol, polypropylene oxide, and various acrylic ester resins are preferable from the viewpoint of degradability. Among these, polyethylene oxide, polypropylene oxide, or acrylic ester resin is more preferable, and polyethylene oxide is particularly preferable.

Examples of acrylic ester resins include polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polyethyl acrylate, polypropyl acrylate, polybutyl acrylate, Examples thereof include polyacrylic acid esters such as polyhydroxyethyl methacrylate, polybenzyl methacrylate, and polyglycidyl methacrylate, and copolymers thereof. When the acrylic ester resin is a copolymer, the acrylic ester component may be 60 mol% or more as a polymerization ratio, and other copolymerizable components such as polyacrylic acid and polystyrene can be polymerized with vinyl. The components may be copolymerized.

Also, for polyethylene oxide and polypropylene oxide, these two types of copolymers are also preferred. Any of acrylic ester resins, polyethylene oxide, and polypropylene oxide having a weight average molecular weight of 100,000 or more is preferable because the thickening effect is high. The content of the thickener in the impurity diffusion composition is preferably in the range of 1% by mass to 20% by mass.

The viscosity of the impurity diffusion composition according to the present invention is not particularly limited, and can be appropriately changed according to the application method or film thickness of the impurity diffusion composition. For example, when the application method of the impurity diffusion composition is a spin coating method, the viscosity of the impurity diffusion composition is preferably 100 [mPa · s] or less. Moreover, when the application | coating method of an impurity diffusion composition is a screen printing method, it is preferable that the viscosity of an impurity diffusion composition is 5,000 [mPa * s] or more and 100,000 [mPa * s] or less.

Here, when the viscosity is less than 1,000 [mPa · s], it is a value measured at a rotation speed of 20 rpm using an E-type digital viscometer based on JIS Z8803 (1991) “Solution Viscosity—Measurement Method”. . When the viscosity is 1,000 [mPa · s] or more, the viscosity is a value measured at a rotational speed of 20 rpm using a B-type digital viscometer based on JIS Z8803 (1991) “Solution Viscosity—Measurement Method”.

The solid content concentration of the impurity diffusion composition according to the present invention is not particularly limited, but is preferably 1% by mass or more and 90% by mass or less. When the solid content concentration of the impurity diffusion composition is in the above range, the diffusibility and storage stability of the impurity diffusion composition are good.

(Semiconductor element manufacturing method)
Next, a method for manufacturing a semiconductor device using the impurity diffusion composition according to the present invention will be described. A method for manufacturing a semiconductor device according to an embodiment of the present invention uses a method for forming an impurity diffusion layer using an impurity diffusion composition containing polysiloxane (A) and an impurity diffusion component (B). is there. A manufacturing method of such a semiconductor element includes a film forming step of forming the impurity diffusion composition film on the semiconductor substrate by applying the impurity diffusion composition described above, and the impurity diffusion composition film into the semiconductor substrate. And a layer forming step of diffusing the impurity diffusion component (B) to form an impurity diffusion layer.

Further, as a preferred embodiment of the present invention, a semiconductor device manufacturing method includes the above-described film formation step, and the impurity diffusion composition film on the semiconductor substrate is irradiated with laser light, and the impurity diffusion composition film is used. And a layer forming step of diffusing the impurity diffusion component (B) in the semiconductor substrate to form an impurity diffusion layer. In particular, in the method of manufacturing a semiconductor device according to the present embodiment, a part of the impurity diffusion composition film is formed by irradiating a part of the impurity diffusion composition film formed on the semiconductor substrate with the above film formation step. A step of forming an impurity diffusion layer by diffusing the impurity diffusion component (B) into the semiconductor substrate, and a portion of the impurity diffusion composition film that has not been irradiated with laser light is treated with an acid or alkali. And a removing step of removing by.

FIG. 1A is a diagram showing an example of a method for manufacturing a semiconductor element according to an embodiment of the present invention. In this embodiment, the manufacturing method applied when manufacturing the semiconductor element for back junction type solar cells is illustrated. In a semiconductor element for a back junction solar cell, a p-type impurity diffusion layer and an n-type impurity diffusion layer are formed on the back surface that is the surface opposite to the light receiving surface of the solar cell.

Specifically, as shown in FIG. 1A, in the method for manufacturing a semiconductor element, first, a first film forming step (step ST101) is performed. In this step ST101, the first conductivity type impurity diffusion composition in the present invention is applied onto a predetermined surface of the semiconductor substrate 1 (the back surface in the solar cell). Thereby, the impurity diffusion composition film 2 is formed on the predetermined surface of the semiconductor substrate 1. The impurity diffusion composition film 2 is a first conductivity type impurity diffusion composition film having a predetermined conductivity type (n-type or p-type).

In the present embodiment, the first conductivity type impurity diffusion composition is an impurity diffusion composition containing the above-described polysiloxane (A) and the first conductivity type impurity diffusion component (B-1). The first conductivity type impurity diffusion component (B-1) is an embodiment of the impurity diffusion component (B) described above (for example, a compound containing a group 13 element or a group 15 element), and the second conductivity type impurity described later. It has a conductivity type different from that of the diffusion component (B-2).

As the semiconductor substrate 1, for example, n-type single crystal silicon having an impurity concentration of 10 ¹⁵ to 10 ¹⁶ [atoms / cm ³ ], polycrystalline silicon, and other elements such as germanium and carbon are mixed. An example is a crystalline silicon substrate. Alternatively, p-type crystalline silicon or a semiconductor substrate other than silicon can be used. The semiconductor substrate 1 preferably has a thickness of 50 [μm] to 300 [μm] and an outer shape of a substantially square shape with sides of 100 [μm] to 250 [μm]. Further, in order to remove slice damage and natural oxide film on each surface of the semiconductor substrate 1, it is preferable to etch each surface of the semiconductor substrate 1 with a hydrofluoric acid solution or an alkaline solution.

Further, a protective film may be formed on the light receiving surface of the semiconductor substrate 1 (the surface opposite to the surface on which the impurity diffusion composition film 2 is formed). This protective film can be formed by a technique such as CVD (chemical vapor deposition) or spin-on-glass (SOG). For example, a known protective film such as silicon oxide or silicon nitride can be applied as the protective film.

Examples of the coating method of the first conductivity type impurity diffusion composition applied to the step ST101 include spin coating, screen printing, ink jet printing, slit coating, letterpress printing, and intaglio printing. . In step ST101, after forming the impurity diffusion composition film 2 by any of these coating methods, the impurity diffusion composition film 2 is in the range of 50 ° C. to 200 ° C. with a hot plate, oven, IR heater or the like. It is preferable to dry for 1 second to 30 minutes. The film thickness of the impurity diffusion composition film 2 after drying is preferably 200 [nm] or more and 5 [μm] or less in consideration of the diffusibility of the impurity diffusion component (B-1) into the semiconductor substrate 1. .

After the above-described step ST101 is completed, a first layer forming step (step ST102) is performed as shown in FIG. 1A. In this step ST102, the impurity diffusion component (B-1) is diffused from the impurity diffusion composition film 2 into the semiconductor substrate 1, thereby forming the impurity diffusion layer 3 in the semiconductor substrate 1. The impurity diffusion layer 3 is a first conductivity type impurity diffusion layer having the same conductivity type as the impurity diffusion composition film 2.

In this embodiment, the impurity diffusion composition film 2 is irradiated with the laser beam 10 to diffuse the impurity diffusion component (B-1) from the impurity diffusion composition film 2 into the semiconductor substrate 1. Specifically, a target portion (for example, a portion forming a desired pattern) of the impurity diffusion composition film 2 is irradiated with the laser beam 10. The impurity diffusion component (B-1) in the impurity diffusion composition film 2 is partially diffused (in a desired pattern) into the semiconductor substrate 1 by heating by the irradiation of the laser beam 10 (hereinafter referred to as “laser heating”). Let As a result, as shown in FIG. 1A, the impurity diffusion layer 3 is formed in a desired pattern in the semiconductor substrate 1. At this time, in the entire impurity diffusion composition film 2, the portion where the impurity diffusion layer 3 is formed by laser heating (the broken line portion in FIG. 1A) may be lost by ablation or remains without being lost. May be.

Further, the laser beam 10 used for the laser heating is not particularly limited, and a known one can be used. For example, as the laser beam 10, a fundamental wave (1064 [nm]), a second harmonic (532 [nm]), a third harmonic (355 [nm]), or a XeCl excimer of an Nd: YAG laser or an Nd: YVO ₄ laser is used. Laser light such as laser (308 [nm]), KrF excimer laser (248 [nm]), ArF excimer laser (198 [nm]) can be used.

The energy density of the laser beam 10 is preferably 0.25 [J / cm ² ] or more and 25 [J / cm ² ] or less. The diffusion time of the impurity diffusion component (impurity diffusion component (B-1) in step ST102) by laser heating is appropriately set so as to obtain desired diffusion characteristics such as the concentration and diffusion depth of the target impurity diffusion component. be able to. For example, the concentration of the impurity diffusion component on the semiconductor substrate surface is preferably such that an impurity diffusion layer of 10 ¹⁹ to 10 ²¹ [atoms / cm ³ ] can be formed. The diffusion atmosphere of the impurity diffusion component by laser heating is not particularly limited and may be the same atmosphere as the atmosphere, or an atmosphere in which the amount of oxygen in the atmosphere is appropriately controlled using an inert gas such as nitrogen or argon It may be.

After the above-described step ST102 is completed, a first removal step (step ST103) is performed as shown in FIG. 1A. In this step ST103, the impurity diffusion composition film 2 remaining on the semiconductor substrate 1 is removed using a cleaning liquid. In the present embodiment, a portion of the impurity diffusion composition film 2 that has not been irradiated with the laser beam 10 remains on the semiconductor substrate 1. In step ST103, such a laser-irradiated portion is removed with a cleaning liquid. As this cleaning solution, for example, a known acid or alkali cleaning solution such as hydrochloric acid, hydrofluoric acid, nitric acid, sulfuric acid, TMAH or KOH can be used. Among these, from the viewpoint that damage to the protective film formed on the semiconductor substrate 1 can be suppressed, it is preferable to use an alkaline cleaning liquid such as TMAH or KOH.

After the above-described step ST103 is completed, a second film formation step (step ST104) is performed as shown in FIG. 1A. In this step ST104, the second conductivity type impurity diffusion composition according to the present invention is applied onto a predetermined surface of the semiconductor substrate 1. Thereby, the impurity diffusion composition film 4 is formed on the predetermined surface of the semiconductor substrate 1. The application method of the second conductivity type impurity diffusion composition is not particularly limited, and a known application method similar to the method of applying the first conductivity type impurity diffusion composition in step ST101 described above may be used. it can.

In this embodiment, the impurity diffusion composition film 4 is a second conductivity type impurity diffusion composition film having a conductivity type different from the conductivity type (first conductivity type) of the impurity diffusion composition film 2 described above. The second conductivity type impurity diffusion composition is an impurity diffusion composition containing the above-described polysiloxane (A) and the second conductivity type impurity diffusion component (B-2). The second conductivity type impurity diffusion component (B-2) is an embodiment of the impurity diffusion component (B) described above (for example, a compound containing a group 13 element or a group 15 element). It has a conductivity type different from that of the diffusion component (B-1).

Also in the step ST104, it is preferable to dry the impurity diffusion composition film 4 after forming the impurity diffusion composition film 4 as in the above-described step ST101. The film thickness of the impurity diffusion composition film 4 after drying is set in consideration of, for example, the diffusibility of the impurity diffusion component (B-2) into the semiconductor substrate 1.

After the above-described step ST104 is completed, a second layer forming step (step ST105) is performed as shown in FIG. 1A. In this step ST105, the impurity diffusion component (B-2) is diffused from the impurity diffusion composition film 4 into the semiconductor substrate 1, thereby forming the impurity diffusion layer 5 in the semiconductor substrate 1. The impurity diffusion layer 5 is a second conductivity type impurity diffusion layer having the same conductivity type as the impurity diffusion composition film 4. That is, the conductivity type (second conductivity type) of the impurity diffusion layer 5 is different from the conductivity type (first conductivity type) of the impurity diffusion layer 3 already formed.

In this embodiment, the impurity diffusion composition film 4 is irradiated with laser light 10 to diffuse the impurity diffusion component (B-2) from the impurity diffusion composition film 4 into the semiconductor substrate 1. Specifically, a target portion of the impurity diffusion composition film 4 (for example, a portion other than the impurity diffusion layer 3 and forming a desired pattern) is irradiated with the laser beam 10, and the target portion is Heat with laser. By this laser heating, the impurity diffusion component (B-2) in the impurity diffusion composition film 4 is partially diffused (in a desired pattern) into the semiconductor substrate 1. As a result, as shown in FIG. 1A, the impurity diffusion layer 5 is formed in a desired pattern in the semiconductor substrate 1. At this time, in the entire impurity diffusion composition film 4, the portion where the impurity diffusion layer 5 is formed by laser heating (the broken line portion in FIG. 1A) may be lost by ablation or remains without being lost. May be.

The laser beam 10 used for the laser heating is not particularly limited, and is a known method similar to the method of laser heating the first conductivity type impurity diffusion composition (impurity diffusion composition film 2) in the above-described step ST102. Things can be used. The diffusion time of the impurity diffusion component by laser heating (impurity diffusion component (B-2) in step ST105) is appropriately set so as to obtain desired diffusion characteristics such as the concentration and diffusion depth of the target impurity diffusion component. be able to. For example, the concentration of the impurity diffusion component on the semiconductor substrate surface is preferably such that an impurity diffusion layer of 10 ¹⁹ to 10 ²¹ [atoms / cm ³ ] can be formed. The diffusion atmosphere of the impurity diffusion component by laser heating is not particularly limited and may be the same atmosphere as the atmosphere, or an atmosphere in which the amount of oxygen in the atmosphere is appropriately controlled using an inert gas such as nitrogen or argon It may be.

After the above-described step ST105 is completed, a second removal step (step ST106) is performed as shown in FIG. 1A. In this step ST106, the impurity diffusion composition film 4 remaining on the semiconductor substrate 1 is removed using a cleaning liquid. In the present embodiment, the laser non-irradiated portion of the impurity diffusion composition film 4 remains on the semiconductor substrate 1. In step ST106, such a laser-irradiated portion is removed with a cleaning liquid. As this cleaning solution, for example, a known acid or alkali cleaning solution such as hydrochloric acid, hydrofluoric acid, nitric acid, sulfuric acid, TMAH or KOH can be used. Among these, from the viewpoint that damage to the protective film formed on the semiconductor substrate 1 can be suppressed, it is preferable to use an alkaline cleaning liquid such as TMAH or KOH.

The semiconductor element 15 according to this embodiment is manufactured by sequentially performing the above-described steps ST101 to ST106. The semiconductor element 15 is suitable as a semiconductor element for a back junction solar cell.

Next, a method for manufacturing a solar cell using the semiconductor element according to the embodiment of the present invention will be described. FIG. 1B is a diagram showing an example of a method for manufacturing a solar cell using a semiconductor element according to an embodiment of the present invention. FIG. 1B illustrates a process after the manufacture of the semiconductor element 15 (see FIG. 1A) used for manufacturing the solar cell according to the present embodiment.

The method for manufacturing a solar cell according to this embodiment includes the method for manufacturing the semiconductor element 15 shown in FIG. 1A. That is, after manufacturing the semiconductor element 15 as described above, the solar cell (back junction solar cell) in the present embodiment can be manufactured using a known method.

For example, in the method for manufacturing a solar cell according to this embodiment, a protective film forming step (step ST201) is performed as shown in FIG. 1B following the manufacturing step of the semiconductor element 15 shown in FIG. 1A. In this step ST201, the protective film 6 is formed on the back surface of the semiconductor substrate 1. The back surface of the semiconductor substrate 1 is the surface opposite to the light receiving surface of the semiconductor element 15 (the lower surface in FIG. 1B), and is the surface on which the impurity diffusion layers 3 and 5 having different conductivity types are formed. It is. In the present embodiment, the protective film 6 is formed on the entire back surface of the semiconductor substrate 1. Examples of the protective film 6 include a laminate of a thermal oxide layer, an aluminum oxide layer, a SiNx layer, and an amorphous silicon layer. Moreover, as a formation method of the protective film 6, vapor deposition methods, such as a plasma CVD method and ALD (atomic layer deposition) method, or the apply | coating method is mentioned, for example.

After the above-described step ST201 is completed, a pattern processing step (step ST202) is performed as shown in FIG. 1B. In this step ST202, the protective film 6 on the back surface of the semiconductor substrate 1 is processed into a desired pattern (pattern processing) by an etching method or the like. Thereby, a plurality of openings 6 a are formed in the protective film 6. Each of the plurality of openings 6 a is for exposing the impurity diffusion layers 3 and 5 formed in the semiconductor substrate 1 in a discrete manner.

After the above-described step ST202 is completed, an electrode formation step (step ST203) is performed as shown in FIG. 1B. In this step ST203, an electrode paste is applied in a pattern to each region including the opening 6a of the protective film 6 on the back surface of the semiconductor substrate 1 by a method such as a stripe coating method or a screen printing method, and the applied electrode paste is applied. Bake. As a result,

contact electrodes

7 and 8 are formed in the respective regions of the semiconductor substrate 1. Among these, one contact electrode 7 is a first conductivity type contact electrode connected to the first conductivity type impurity diffusion layer 3. The other contact electrode 8 is a second conductivity type contact electrode connected to the second conductivity type impurity diffusion layer 5. Through the above steps, the back junction solar cell 9 according to this embodiment is manufactured.

In each manufacturing method of the semiconductor element 15 and the solar cell 9 described above, “first conductivity type” and “second conductivity type” are different conductivity types, one representing p-type and the other representing n-type. To express. For example, if the first conductivity type is p-type, the second conductivity type is n-type.

In addition, regarding another example of a method for manufacturing a semiconductor element using the impurity diffusion composition according to the present invention, selection of various solar cells such as a double-sided power generation type solar cell, a PERC type solar cell, and a PERT type solar cell is possible. It can also be applied to the formation of an emitter layer.

The impurity diffusion composition according to the present invention and the method for manufacturing a semiconductor device using the same are not limited to the above-described embodiments, and various modifications such as design changes may be added based on the knowledge of those skilled in the art. An embodiment to which such a modification is possible is also included in the scope of the present invention.

Further, the impurity diffusion composition according to the present invention is a photovoltaic device such as a solar cell, or a semiconductor device in which an impurity diffusion layer is patterned on the surface of a semiconductor substrate, such as a transistor array, a diode array, a photodiode array, or a transducer. Etc.

Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to the following examples.

(Evaluation of sheet resistance)
The sheet resistance value evaluation is for evaluating the sheet resistance value (also referred to as surface resistivity) of the impurity diffusion layer in the semiconductor substrate. In the evaluation of the sheet resistance value, the semiconductor substrate for evaluation was an n-type silicon wafer (Ferrotech Silicon Co., Ltd., surface resistivity 410 [Ω / □]) cut to 3 cm × 3 cm. This silicon wafer was immersed in a 1% hydrofluoric acid aqueous solution for 5 minutes, washed with water, air blown, and then heat treated at 100 ° C. for 5 minutes with a hot plate.

Next, the impurity diffusion composition to be measured is applied to a silicon wafer for evaluation by a known spin coating method so that the prebaked film thickness is about 400 nm, and the impurity diffusion to be measured is spread on the silicon wafer surface. A coating film of the composition (that is, an impurity diffusion composition film) was formed. Subsequently, this silicon wafer was pre-baked at 140 ° C. for 3 minutes. Thereafter, the pre-baked film thickness (film thickness after pre-baking) of the impurity diffusion composition film on the silicon wafer surface was measured with a surface shape measuring device (Surfcom 1400, manufactured by Tokyo Seimitsu Co., Ltd.).

Subsequently, each silicon wafer on which the impurity diffusion composition film is formed by the above-described method is irradiated with a predetermined laser beam in a range of 1 cm × 1 cm to diffuse the impurities in the impurity diffusion composition film into each silicon wafer. Component (B) was thermally diffused. At this time, the laser beam was an Nd: YVO ₄ laser. In this laser beam, the wavelength was 355 [nm], the pulse width was 25 [ns], and the frequency was 20 [kHz]. The laser output was 1 [W]. The spot shape was a rectangle of 40 [μm]. The scan speed was 3000 [mm / s].

After thermal diffusion of the impurity diffusion component (B), each silicon wafer was immersed in a 1% by mass TMAH aqueous solution at 23 ° C. for 10 minutes. Thereby, the impurity diffusion composition film (diffusion agent) cured by the laser beam irradiation was peeled off. Each silicon wafer after the film is peeled is subjected to p / n determination using a p / n determiner, and the surface resistance of the diffusion portion of the impurity diffusion component (B) in each silicon wafer is determined by four probes. A sheet resistance value was measured using a type surface resistance measuring device (RT-70V, manufactured by Napson Corporation). The sheet resistance value is an index of the diffusibility of the impurity diffusion component (B) in the semiconductor substrate. A smaller sheet resistance value means a larger diffusion amount of the impurity diffusion component (B).

(Evaluation of cleanability of dry film)
Detergent evaluation of the dry film evaluates the detergency of the impurity diffusion composition film (dry film) remaining in a dry state on the semiconductor substrate surface after the thermal diffusion of the impurity diffusion component (B) by laser light irradiation. It is. In the evaluation of the detergency of the dried film, the semiconductor substrate for evaluation was an n-type silicon wafer (Ferrotech Silicon Co., Ltd., surface resistivity 410 [Ω / □]) cut to 3 cm × 3 cm. This silicon wafer was immersed in a 1% hydrofluoric acid aqueous solution for 5 minutes, washed with water, air blown, and then heat treated at 100 ° C. for 5 minutes with a hot plate.

Next, the impurity diffusion composition to be measured is applied to a silicon wafer for evaluation by a known spin coating method so that the prebaked film thickness is about 400 nm, and the impurity diffusion to be measured is spread on the silicon wafer surface. A composition film was formed. Subsequently, this silicon wafer was pre-baked at 140 ° C. for 3 minutes. Thereby, the impurity diffusion composition film to be measured was used as the dry film (pre-baked film). Thereafter, the silicon wafer was immersed in a cleaning solution, and the time until the prebaked film on the silicon wafer surface was dissolved was measured. In this cleaning performance evaluation, the case where the pre-baked film is dissolved within 1 minute is judged as excellent, the case where the pre-baked film is dissolved within 3 minutes is judged as good, and the case where it takes 5 minutes or more to dissolve the pre-baked film. Judged as bad.

Example 1
In Example 1, the polysiloxane (A) was synthesized as follows, and the impurity diffusion composition containing the obtained polysiloxane (A) was evaluated for sheet resistance and dry film detergency. .

In the synthesis of polysiloxane (A) of Example 1, 15.73 g (0.06 mol) of 3-trimethoxysilylpropyl succinic acid and 155.29 g (1.14 mol) of methyltrimethoxy were added to a 500 mL three-necked flask. Silane and 192.29 g of propylene glycol monomethyl ether were charged, and an aqueous phosphoric acid solution prepared by dissolving 0.5 g of formic acid in 64.0 g of water was added over 30 minutes while stirring at 40 ° C. After completion of dropping, the resulting solution was stirred at 40 ° C. for 1 hour, then heated to 70 ° C. and stirred for 30 minutes. Thereafter, the temperature of the oil bath was raised to 115 ° C. One hour after the start of temperature increase, the internal temperature of this solution reached 100 ° C., and from this time, this solution was heated and stirred (internal temperature was 100 ° C. to 110 ° C.). The solution thus obtained was cooled in an ice bath to obtain a polysiloxane solution. The obtained polysiloxane solution had a solid content concentration of 42.0% by mass. From this polysiloxane solution, the polysiloxane (A) of Example 1 was obtained.

Using the polysiloxane (A) synthesized as described above, the impurity diffusion composition of Example 1 was adjusted with the composition ratio, molar ratio, and content of each composition described in Table 1 described later. Evaluation of the sheet resistance value of Example 1 and evaluation of the cleaning property of the dry film were performed on the impurity diffusion composition of Example 1. As a result, as shown in Table 2 described later, a good value (that is, good diffusibility of the impurity diffusion component (B) (hereinafter referred to as “impurity diffusibility”)) is obtained in the sheet resistance value evaluation, and the detergency evaluation It was excellent.

(Examples 2 to 8)
In Examples 2 to 8, as in Example 1 described above, polysiloxane (A) was synthesized at the ratio of the organosilane compound described in Table 1, and the composition ratio, molar ratio, and ratio of each composition described in Table 1 were synthesized. The impurity diffusion compositions of Examples 2 to 8 were adjusted according to the content. In Examples 2 to 8, for the impurity diffusion compositions obtained in each Example, sheet resistance value evaluation and dry film detergency evaluation were performed. As a result, as shown in Table 2, in each of Examples 2 to 8, both the sheet resistance value (impurity diffusibility) and the cleaning property evaluation were good. In particular, the content ratio (molar ratio) of the organosilane having at least one of a carboxyl group and a dicarboxylic anhydride structure in the polysiloxane (A) is a Si atom mole of the entire polysiloxane (A) derived from the organosilane. In Examples 2 to 5 and 8, in which the molar ratio of Si atoms to the number was 5 mol% or more and 30 mol% or less, the impurity diffusibility was good and the detergency evaluation was excellent.

Example 9
In Example 9, “X-22-3701E” (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) was used as the polysiloxane (A) having a carboxyl group. The polysiloxane (A) (8 g), phosphoric acid (6 g), BYK333 (0.03 g), and propylene glycol monomethyl ether (85.97 g) were mixed to obtain the impurity diffusion composition of Example 9. It was adjusted. In Example 9, with respect to the impurity diffusion composition thus obtained, sheet resistance evaluation and dry film detergency evaluation were performed. As a result, as shown in Table 2, a good value (good impurity diffusibility) was obtained in the sheet resistance value evaluation, and the detergency evaluation was good.

Although not shown in Table 1, the content ratio of the component derived from the organosilane having a carboxyl group in the polysiloxane “X-22-3701E” of Example 9 is the entire polysiloxane derived from the organosilane. The Si atom mole ratio relative to the number of moles of Si atoms is less than 5 mol%.

(Comparative Example 1)
In Comparative Example 1, in the same manner as in Example 1 described above, polysiloxane was synthesized at the ratio of the organosilane compound described in Table 1, and the composition ratio, molar ratio, and content of each composition described in Table 1 were compared. 1 impurity diffusion composition was prepared. The sheet resistance value evaluation of Comparative Example 1 and the cleaning property evaluation of the dried film were performed on the impurity diffusion composition of Comparative Example 1 obtained as described above. As a result, as shown in Table 2, the sheet resistance value (impurity diffusibility) was good, but the detergency evaluation was bad.

As described above, the impurity diffusion composition according to the present invention and the method for manufacturing a semiconductor device using the same are as follows. Impurity diffusibility with respect to a semiconductor substrate and cleaning performance of an impurity diffusion composition film remaining on the semiconductor substrate after impurity diffusion. It is suitable for improving both.

DESCRIPTION OF SYMBOLS 1

Semiconductor substrate

2, 4 Impurity

diffusion composition film

3, 5 Impurity diffusion layer 6 Protective film

6a Opening part

7, 8 Contact electrode 9 Solar cell 10 Laser beam 15 Semiconductor element

Claims

Polysiloxane (A),
An impurity diffusion component (B);
And the polysiloxane (A) contains at least one of a carboxyl group and a dicarboxylic anhydride structure.
The impurity diffusion composition according to claim 1, wherein the polysiloxane (A) is a polysiloxane represented by the following general formula (1).

(In the general formula (1), R 1 represents a substituent containing at least one of a carboxyl group and a dicarboxylic anhydride structure, and a plurality of R 1 may be the same or different from each other. R 2 , R 3 and R 4 are a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an acyl group having 2 to 6 carbon atoms, or 6 to 6 carbon atoms Any one of 15 aryl groups, and a plurality of R 2 , R 3 and R 4 may be the same or different from each other, n and m each represent a constituent ratio (%) of each component in parentheses; n + m = 100, and n: m = 5: 95 to 30:70.)
3. The impurity diffusion composition according to claim 2, wherein R 1 in the general formula (1) includes a group represented by any one of the following general formulas (2) to (6).

(In the general formulas (2) to (6), R 5 , R 7 , R 8 and R 9 represent a divalent organic group having 1 to 20 carbon atoms. R 6 represents a hydrogen atom or 1 to Represents an alkyl group of 3. R 10 , R 11 and R 12 each represents a single bond, a chain aliphatic hydrocarbon group having 1 to 10 carbon atoms, a cyclic aliphatic hydrocarbon group having 3 to 16 carbon atoms, or a carbon number Represents a 2-6 alkylcarbonyloxy group, a carbonyl group, an ether group, an ester group, an amide group, an aromatic group having 6 to 16 carbon atoms, or a divalent group having any one of these. The atom is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 16 carbon atoms, an alkylcarbonyloxy group having 2 to 6 carbon atoms, a hydroxy group, an amino group, a carboxyl group, or Optionally substituted with a thiol group, h, j, k and And l represents an integer of 0 to 3.)
The impurity diffusion composition according to any one of claims 1 to 3, wherein the content of the impurity diffusion component (B) is 0.1 mass% or more and 20 mass% or less.
The impurity diffusion component (B) contains at least one selected from phosphoric acid, diphosphorus pentoxide, polyphosphoric acid, phosphoric acid ester, boron oxide, boric acid, boric acid ester, boronic acid, and boronic acid ester. The impurity diffusion composition according to any one of claims 1 to 4, wherein:
The impurity diffusion component (B) contains at least one selected from boric acid, boronic acid, boric acid ester, and boronic acid ester, and further contains water and a water-soluble binder. 5. The impurity diffusion composition according to any one of 1 to 4.
The impurity diffusion composition according to claim 6, wherein the water-soluble binder is polyvinyl alcohol.
A film forming step of forming an impurity diffusion composition film by applying the impurity diffusion composition according to any one of claims 1 to 7 on a semiconductor substrate;
A layer forming step of diffusing an impurity diffusion component from the impurity diffusion composition film into the semiconductor substrate to form an impurity diffusion layer;
The manufacturing method of the semiconductor element characterized by the above-mentioned.
A film forming step of forming an impurity diffusion composition film by applying the impurity diffusion composition according to any one of claims 1 to 7 on a semiconductor substrate;
A layer forming step of irradiating the impurity diffusion composition film with laser light to diffuse an impurity diffusion component from the impurity diffusion composition film into the semiconductor substrate to form an impurity diffusion layer;
The manufacturing method of the semiconductor element characterized by the above-mentioned.
A film forming step of forming an impurity diffusion composition film by applying the impurity diffusion composition according to any one of claims 1 to 7 on a semiconductor substrate;
A layer forming step of forming an impurity diffusion layer by irradiating a part of the impurity diffusion composition film with laser light to diffuse an impurity diffusion component from the part of the impurity diffusion composition film into the semiconductor substrate;
A removal step of removing the non-laser irradiated portion of the impurity diffusion composition film that has not been irradiated with the laser light with an acid or alkali,
The manufacturing method of the semiconductor element characterized by the above-mentioned.