TW201245312A - Resin paste, solar cell, method for manufacturing solar cell, resin film, and semiconductor device - Google Patents

Abstract

A resin paste which contains: a mixed solvent that contains a first polar solvent (A1) and a second polar solvent (A2) having a boiling point lower than the boiling point of the first polar solvent (A1) at a mass ratio of from 6:4 to 9:1; a heat-resistant resin (B) that is soluble in the mixed solvent at room temperature; and a heat-resistant resin (C) that is soluble in the first polar solvent (A1) but insoluble in the second polar solvent (A2) and the mixed solvent at room temperature. The resin paste is obtained by dispersing the heat-resistant resin (C) in a solution that contains the mixed solvent and the heat-resistant resin (B).

Description

[Technical Field] The present invention relates to a resin paste, a method for producing a solar cell using the resin paste, and a solar cell, a resin film, and a semiconductor device including the resin film produced by the method. [Prior Art] A resin such as a polyimide resin excellent in heat resistance and mechanical properties has been used as a surface protective film, an interlayer insulating film or a stress relieving material for a semiconductor element in the field of electronics. In recent years, as a method of forming an image of a resin film used in such applications, attention has been paid to a screen printing method which does not require exposure to complicated steps such as 'development or etching. In the screen printing method, a thixotropy resin paste is used as a component constituting, for example, a base resin, a coating, and a solvent. In the resin paste, as the material for imparting thixotropy, cerium oxide microparticles or polyimide microparticles are often used. However, when the resin paste containing the materials is dried by heating, many voids or bubbles remain between the interfaces of the material. Therefore, the film strength and electrical insulating properties of the resin film formed of the resin paste are insufficient. In view of such a problem, for example, in Patent Document 1, it is disclosed that a resin paste obtained by mixing an organic mash (soluble mash) which is compatible with a base resin and a solvent during heating in a base resin and a solvent is used to form a resin pattern. type. Further, Patent Document 2 discloses a technique of adding a low elastic coating or a liquid rubber to impart properties such as low elasticity to the resin paste. -5-201245312 [PRIOR ART DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PRIOR ART The resin film obtained by the resin paste may have irregularities on the surface of the resin film due to agglomerates of non-soluble materials such as low-elastic materials, organic materials remaining after being enlarged, and other foreign matters, thereby causing surface flatness. reduce. When the wiring after the formation of the resin film is formed, the unevenness on the surface of the resin film may cause abnormal plating or disconnection of the wiring. Accordingly, an object of the present invention is to provide a resin paste which can be used for screen printing to form a resin film having excellent resolution and excellent surface flatness, > a method for producing a solar cell using the resin paste, and a method for producing the same using the method A solar cell, a resin film, and a semiconductor device including the resin film. [Means for Solving the Problem] The present invention provides a resin paste comprising: a first polar solvent (A1) at a mass ratio of 6:4 to 9:1 and a boiling point higher than the first polar solvent (A1) a mixed solvent of a second polar solvent (A2) having a low boiling point, a heat resistant resin (B) soluble in a mixed solvent at room temperature, and a first polar solvent (A1) soluble in a room temperature but insoluble in the first The bipolar solvent (A2) is insoluble in the heat-resistant resin (C) of the mixed solvent; and the heat-resistant resin (C) is dispersed in 201245312 in a solution containing the mixed solvent and the heat-resistant resin (B). By setting the mass ratio of the first polar solvent (A1) to the second polar solvent (A2) to 6:4 to 9:1, it is possible to obtain a fluidity in which the resin paste is less likely to collapse and the printing workability is extremely high. Thereby, a resin paste which can be used for screen printing can be obtained. At the same time, the solubility of the heat-resistant resin (C) acting as a coating material in the resin paste rises during the formation of the resin film, so that a resin film having excellent surface flatness and excellent resolution can be formed. Here, in terms of improving the screen printing property of the resin paste, the boiling point difference between the boiling point of the first polar solvent (A1) of the resin paste of the present invention and the second polar solvent (A2) is preferably 1〇. ~l〇〇°C. Further, the heat resistant resin (B) and the heat resistant resin (C) are preferably each independently selected from the group consisting of a polyamide resin, a polyimide resin, a polyamide resin, or a polyimine resin and a poly At least one of the precursors of the amidoxime resin. Thereby, a resin film excellent in heat resistance and mechanical properties can be obtained. Further, the heat-resistant resin (C) dispersed in the above solution may have a particle shape having an average particle diameter of 50 μm or less. The present invention further provides a method for manufacturing a solar cell and a solar cell manufactured by the method, the method comprising the steps of: printing a resin paste on a side surface of a substrate having a negative electrode and a positive electrode, and 00 to 45 (Step of heat-drying the resin paste of the screen printing by TC. The solar cell manufactured by the method of the present invention is excellent in surface flatness of the resin film, so that plating abnormality or disconnection of the wiring is reduced, and thus reliability is excellent. Furthermore, the present invention provides a resin film by a method comprising the steps of printing the above-mentioned resin paste on a substrate and heating the resin paste printed on the stencil 201245312 at 100 to 450 °C. Further, the present invention provides a semiconductor device including the above-described resin film. The semiconductor device of the present invention includes the resin film of the present invention, so that plating abnormality or disconnection of the wiring can be reduced. Therefore, the reliability is excellent. [Effect of the Invention] According to the present invention, it is possible to provide a screen with a precision solution that can be used for screen printing. A resin paste of a resin film having excellent surface flatness, a method for producing a solar cell using the resin paste, a solar cell produced by the method, a resin film, and a semiconductor device including the resin film. [Embodiment] Hereinafter, depending on the case A resin paste of the present embodiment, a method for producing a solar cell using the resin paste, a solar cell produced by the method, a resin film, and a semiconductor device including the resin film will be described with reference to the drawings, but the present invention is not The size ratio of the pattern may be different from the ratio of the actual size. <Resin paste> First, the components constituting the resin paste of the present embodiment will be described. The resin paste of the present embodiment contains the mass. Ratio 6 : 4 to 9 : 1 mixed solvent containing a first polar solvent (A 1 ) and a second polar solvent (A2) having a boiling point lower than the boiling point of the first polar solvent (A 1 ), at room temperature It is soluble in the heat-resistant resin (B) of the mixed solvent of the polar solvent (A 1) and the second polar solvent (A2) in the 201245312, and is soluble in the first at room temperature. The solvent (A1) is insoluble in the second polar solvent (A2) and is insoluble in the heat resistant resin (C) of the mixed solvent of the first polar solvent (A1) and the second polar solvent (A2). The "room temperature" in the specification is 25 ° C. Since the heat resistant resin (B) is soluble in a mixed solvent of the first polar solvent (A1) and the second polar solvent (A2) at room temperature, the heat resistant resin (C) Is insoluble in a mixed solvent of the first polar solvent (A1) and the second polar solvent (A2) at room temperature, so that the heat resistant resin (C) is dispersed in the first polar solvent (A1) and the second in the resin paste. In the mixed solvent of the polar solvent (A2) and the heat-resistant resin (B), it acts as a coating material, whereby the thixotropy of the resin paste can be adjusted so that the resin paste can be used for screen printing. In addition, when the resin paste is heated to a temperature at which the heat resistant resin (C) is dissolved, the heat resistant resin (C) is dissolved and the mash disappears. Thereby, the precision of the surface of the resin film can be improved while imparting a precise resolution. As the first polar solvent (A 1) and the second polar solvent (A2), for example, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monoethyl ether are exemplified. a polyether alcohol solvent such as tetraethylene glycol monomethyl ether or tetraethylene glycol monoethyl ether; diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol Dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol dipropyl ether, triethylene glycol dibutyl ether 'tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, An ether solvent such as tetraethylene glycol dipropyl ether or tetraethylene glycol dibutyl ether; a sulfur-containing solvent such as dimethyl hydrazine, diethyl hydrazine, dimethyl hydrazine or cyclopentanyl: ethyl acetate Ester, butyl acetate, acetic acid-9-201245312 fiber solvent, ethyl fiber solvent acetate, butyl phthalate solvent acetate ester solvent; methyl ethyl ketone, methyl isobutyl ketone, cyclohexyl Ketone solvents such as ketone and acetophenone; N-methylpyrrolidone, dimethylacetamide, dimethylformamide, 1,3-3-dimethyl-3,4,5,6-tetrahydro-2 1Η)-pyrimidinone, 1,3 -dimethyl-2-mi a nitrogen-containing solvent such as ketone or the like; an aromatic hydrocarbon solvent such as toluene or xylene; r-butyrolactone, r-valerolactone, 7-caprolactone, r·heptanolactone, α-ethenyl group a lactone solvent such as -r-butyrolactone or ε-caprolactone; an alcohol solvent such as butanol, octanol, ethylene glycol or glycerin; a phenol system such as phenol, cresol or xylenol; Solvents, etc. The combination of the first polar solvent (Α1) and the second polar solvent (Α2) may be appropriately selected from the solvents according to the types of the heat resistant resin (Β) and the heat resistant resin (C). As the first polar solvent (A 1 ), preferred are Ν-methylpyrrolidone, dimethylacetamide, dimethylformamide, 1,3-dimethyl-3,4,5,6-tetra. a nitrogen-containing solvent such as hydrogen-2(H)-pyrimidinone or 1,3-dimethyl-2-imidazolidinone; dimethyl sulfonium 'diethyl fluorene, dimethyl hydrazine, and diethyl a sulfur-containing solvent such as quinone, dimethyl hydrazine or cyclopentanyl; r-butyrolactone, r-valerolactone, r-caprolactone, r-heptanolactone, α-ethenyl-r a lactone solvent such as butyrolactone or ε-caprolactone: a ketone solvent such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone or acetophenone; butanol, octanol and ethylene An alcohol solvent such as an alcohol or glycerin. The heat-resistant resin (Β) and the heat-resistant resin (C) described later are each independently selected from the group consisting of a polyamide resin, a polyimide resin, a polyamide resin, or a polyimide resin and a polyamide. When at least one of the precursors of the quinone imine resin is -10- 201245312 'The first polar solvent (a 1) is preferably r-butyrolactone. The second polar solvent (A2) is preferably exemplified by diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyric acid, triethylene glycol monocarboxylic acid, and the like. Ethylene glycol diacetic acid, triethylene glycol dipropyl ether, triethylene glycol dibutyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diacetic acid, tetraethylene glycol dipropyl ether, tetraethylene glycol An ether solvent such as butyl ether; diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol A polyether alcohol-based solvent such as diethyl ether; an ester solvent such as ethyl acetate, butyl acetate, acetic acid fiber solvent, ethyl fiber solvent acetate or butyl hydrazine solvent acetate. The heat resistant resin (B) and the heat resistant resin (c) described later are each independently selected from the group consisting of a polyamide resin, a polyimide resin, a polyamide resin, or a polyimide resin and a polyamide. When at least one of the precursors of the quinone imine resin is used, the second polar solvent (A 2 ) is preferably a polyether alcohol solvent or an ester solvent, and the present embodiment is improved from the viewpoint of improving the screen printing property of the resin paste. The boiling point difference between the boiling point of the first polar solvent (A1) and the second polar solvent (A2) of the resin paste of the form is preferably from 10 to 100 ° C, more preferably from 10 ° C to 50 ° C, most preferably 10 °. C ~ 30 ° C. Further, the boiling points of both the first polar solvent (A1) and the second polar solvent (A2) are from the viewpoint of the usable time of the resin paste at the time of screen printing. It is preferably l 〇〇 ° C or more, more preferably 150 ° C or more. The heat resistant resin (B) and the heat resistant resin (C) are preferably independently selected from the group consisting of polyamine resins, polyimine resins, polyamidoximine resins, or polyimine resins and polyamines. At least one of the precursors of the quinone imine resin. To -11 - 201245312, in the case of polyamine resin, polyimine resin, polyamidimide resin, or polyamidene resin and polyamidimide resin precursor, by way of example, for example A result of reacting an aromatic, aliphatic or alicyclic diamine compound with a polycarboxylic acid having 2 to 4 carboxyl groups. The term "polyimine" resin and the precursor of the polyamidimide resin also refers to a polylysine which is formed by dehydration ring closure to form a polyimine resin or a polyamidoximine resin. Further, the heat resistant resin (C) is preferably soluble in the above mixed solvent when it is heated, for example, at 60 ° C or higher (preferably 60 to 200 ° C, more preferably 100 to 180 ° C). As the aromatic, aliphatic or alicyclic diamine compound, for example, an alkyl group having an extended aryl group, an alkyl group which may have an unsaturated bond, or a stretched alkyl group which may have an unsaturated bond or a combination of these groups may be exemplified. Amine compound. The groups may also be bonded through a carbon atom, an oxygen atom, a sulfur atom, a sand atom or a combination of the atoms. Further, a hydrogen atom bonded to a carbon skeleton of an alkyl group may be substituted with a fluorine atom. From the viewpoint of heat resistance and mechanical strength, an aromatic diamine is preferred. As the polycarboxylic acid having 2 to 4 carboxyl groups, a dicarboxylic acid or a reactive acid derivative thereof, a tricarboxylic acid or a reactive acid derivative thereof, or a tetracarboxylic dianhydride can be exemplified. The compound may also be a dicarboxylic acid, a tricarboxylic acid or a reactive acid derivative having a carboxyl group bonded to a cycloalkyl group which may have a crosslinked structure or a non-saturated bond in the aryl group or the ring, or An aryl group or a tetracarboxylic dianhydride having a carboxyl group bonded to a cycloalkyl group having a crosslinked structure or a non-saturated bond, a dicarboxylic acid, a tricarboxylic acid or the reactive acid derivative and a tetracarboxylic acid The acid dianhydride can also be bonded through a single bond or through a carbon atom, an oxygen atom, a sulfur atom, a helium atom or a combination of such atoms. Further, the hydrogen atom bonded to the carbon skeleton of the alkylene group may be substituted with a fluorine atom by -12-201245312. From the viewpoint of heat resistance and mechanical strength, tetracarboxylic dianhydride is preferred among the compounds. The combination of an aromatic, aliphatic or alicyclic diamine compound and a polycarboxylic acid having 2 to 4 carboxyl groups can be appropriately selected depending on the reactivity and the like. The reaction can be carried out without using a solvent or in the presence of an organic solvent. The reaction temperature is preferably from 25 t to 250 ° C, and the reaction time can be appropriately selected depending on the batch size, the reaction conditions employed, and the like. The method of dehydrating the polyimide imide resin precursor or the polyamidimide resin precursor to form a polyimine resin or a polyamidoximine resin is also not particularly limited, and a general method can be used. For example, a thermal ring closure method in which dehydration and ring closure by heating under normal pressure or reduced pressure, a chemical ring closure method using a dehydrating agent such as acetic anhydride in the presence or absence of a catalyst, or the like can be used. The thermal closed loop method preferably removes the water produced by the dehydration reaction to the outside of the system. At this time, it is carried out by heating the reaction solution at 80 to 400 ° C, preferably 100 to 250 ° C. In this case, a solvent which can be azeotroped with water such as benzene, toluene or xylene may be used in combination and removed by azeotropy with water. The chemical ring closure method is preferably carried out at 0 to 1 20 ° C, preferably 1 Torr to 80 ° C in the presence of a chemical dehydrating agent. As the chemical dehydrating agent, for example, an acid anhydride such as acetic anhydride, propionic anhydride, butyric anhydride or benzoic anhydride, or a carbodiimide compound such as dicyclohexylcarbodiimide or the like is preferably used. In this case, a substance which promotes the cyclization reaction such as pyridine, isoquineline, trimethylamine 'triethylamine, aminopyridine or imidazole is preferably used. The chemical dehydrating agent is used in an amount of from 90 to 600 mol% relative to the total amount of the diamine compound. The substance which promotes the cyclization reaction is used in an amount of from 4 to 300 mol% based on the total amount of the diamine compound. Further, a dehydration catalyst such as a triphenyl phosphite, a tricyclohexyl phosphate such as sub--13-201245312, a phosphorus compound such as triphenyl phosphate, phosphoric acid or phosphorus pentoxide, or a boron compound such as boric acid or anhydrous boric acid may be used. . The reaction solution in which the hydrazine imidization is completed by the dehydration reaction is injected in a large excess to the first polar solvent (A1) and the second polar solvent (A2), and is compatible with the heat resistant resins (B) and (C). In a solvent such as a weak solvent such as methanol or water such as methanol or the like, a resin precipitate is obtained and filtered. By drying the solvent, a polyimide resin or a polyimide resin can be obtained. . In order to reduce residual ionic impurities and the like, a thermal closed loop method is preferred. The type of the preferred first polar solvent (A 1 ) and the second polar solvent (a 2 ) can be determined depending on the type of the heat resistant resin (B) and the heat resistant resin (C). A preferred combination (mixed solvent) of the first-polar solvent (A1) and the second polar solvent (A2) is exemplified by, for example, the following two types (a) and (b). (a) First polar solvent (Al): the above nitrogen-containing solvent such as N-methylpyrrolidone or dimethylacetamide; the above-mentioned sulfur-containing solvent such as dimethyl hydrazine; T-butyrolactone; The lactone solvent; the phenol solvent such as xylenol; and the ketone solvent such as the second solvent (A2): the ether solvent such as diethylene glycol dimethyl ether: cyclohexanone; The above ester solvent such as butyl cellosolve acetate: the above alcohol solvent such as butanol; or a combination of the above aromatic hydrocarbon solvents such as xylene. (b) First polar solvent (A1): the above ether solvent such as tetraethylene glycol dimethyl ether: the above ketone solvent such as cyclohexanone, and the second polar solvent (A2): butyl cellosolve acetate And the above-mentioned ester solvent such as ethyl acetate; the above alcohol solvent such as butanol or the like; - the above polyether alcohol solvent such as diethylene glycol monoethyl ether; and the above aromatic hydrocarbon solvent such as xylene; combination. The combination of the heat resistant resin (B) and the heat resistant resin (C) which are suitable for the mixed solvent of the type (a) is, for example, the following. Heat-resistant resin (B) - a resin having at least one structural unit represented by the following formulas (1) to (10), and a heat-resistant resin (C) having the following formula (1 1) to (19) A combination of resins representing at least one of the structural units. [Chemical 1]

In the formula (1), X represents -ch2-, -〇-, -co-, -so2- or a group represented by the following formulas (a) to (1), and in the formula (1), P is an integer of from 1 to 100. 15- 201245312

-16- 201245312

In the formula (2), R1 and R2 are each a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and may be the same or different from each other. X is the same as X in the formula (1). [Chemical 4]

In the formula (3), Μ is a group represented by the following formula (c), (h), (i) or (1), and in the formula (i), p is an integer of from 1 to 100. -17- 201245312

-18- 201245312 In the formula (5), X is the same as X of the formula (1). [化8]

In the formula (6), R3 and R4 are each a methyl group, an ethyl group, a propyl group or a phenyl group, and may be the same or different from each other, and X is the same as X of the formula (1). [Chemistry 9]

[化10]

In the formula (8), X is 0 or 2, and X is the same as X of the formula (1). [11]

-19- 201245312 [Chem. 12]

In the formula (1 1), Y is a group represented by the following formula (a), (C) or (h). [Chem. 14]

-20- 201245312 [Chem. 15]

In the formula (12), Y is the same as Y of the formula (11). Moreover, the parts of * are bonded to each other (the same applies hereinafter).

[Chem. 17]

In the formula (14), Ζ is -CH2-, -0-, -CO-, -S02- or a group represented by the following formula (a) or (d). -21 - 201245312 [Chem. 18]

[Chem. 20]

In the formula (16), Z is the same as Z of the formula (14). [Chem. 21]

-22- 201245312 [Chem. 22]

[Chem. 24]

In the formula (20), 'X is the same as X of the formula (1), and ^ and m each independently represent an integer of 1 or more. The ratio of η to m (n/m) is preferably from 8〇/2〇 to 30/70, more preferably from 70/30 to 50/50. In the above combination, it is preferred to use a lactone solvent or a nitrogen-containing solvent as the first polar solvent (A), and an ether solvent or an ester solvent as the second polar solvent (A 2) as a heat resistant resin. A resin having a structural unit represented by the formula (1) is used, and a resin having a structural unit represented by the formula (20) or the formula (16) is used as the heat-resistant resin (C). The combination of the heat resistant resin (B) and the heat resistance -23-201245312 (C) in the mixed solvent of the type (b) is exemplified by, for example, the following. Heat-resistant resin (B): a resin having at least one structural unit represented by the following formulas (2 1) and (22), or a polyoxyalkylene quinone imine having a structural unit represented by the above formula (6), And a heat-resistant resin (C): a polyether amidoxime which has a structural unit represented by the above formula (1) (but X represents a base represented by the following formula (a) or (b)), or has At least one of the structural units represented by the above formulas (5) to (9) (except for the case where X in the above formulas (5), (6), and (8) represents a group of the following formula (a)) A combination of quinones. [Chem. 25]

[Chem. 26]

_r5—木木 H3 ch3

In the formula (22), Z1 is a group represented by 〇- and -CO-(1). R5 and R6 are each J; -, -C0- or the following formula (4), (e), (1) or the group -24-201245312 represented by the following formula (m) or (η), respectively, which may be the same or different from each other . r is an integer from 1 to 100. [化27] CH34ICH3 \1/

H3.LH3c1sIC - ο F3IF3H31H3H31H3οιιοϋο οϋοοΗ—ο CISIC (8) \^/

\n/ /IV

[. 28]

-25- 201245312 [Chem. 29]

0— (b) Ο1 (a) The order of raw material input when cf3 modulates the resin paste is not particularly limited. For example, the raw material of the resin paste may be mixed at one time, or the first polar solvent (A1) and the second polar solvent (A2) may be first mixed, and the heat resistant resin (B) may be mixed in the mixed solvent, followed by The heat resistant resin (C) is added to the mixed solution of the polar solvent (A1), the second polar solvent (A2), and the heat resistant resin (B). Preferably, the raw material mixture of the above resin paste is used in the first polar solvent (A1). In the mixed solution of the second polar solvent (A2) and the heat resistant resin (B), the mixture is heated until the temperature at which the heat resistant resin (C) is sufficiently dissolved, and the mixture is sufficiently stirred while stirring. The resin paste obtained as described above is dispersed in a mixed solution containing the first polar solvent (A1), the second polar solvent (A2) and the heat resistant resin (B) at room temperature. That is, the heat-resistant resin (C) is present in the resin paste as a coating material, and the resin paste can be imparted with a thixotropic property particularly suitable for screen printing. The heat-resistant resin (C) dispersed in the resin paste may be in the form of particles having an average particle diameter of -26 to 201245312 50 μηι or less, preferably 0.01 to ΙΟμηι, more preferably 0.1 to 5 μΓη. Further, the maximum particle diameter is preferably 1 μηηι, more preferably 5 μιη. The average particle diameter and the maximum particle diameter of the heat-resistant resin (C) can be measured by using a particle size distribution measuring device SALD-2200 manufactured by Shimadzu Corporation. The mixing ratio of the first polar solvent (Α1) and the second polar solvent (Α2) depends on the type of the heat resistant resin (Β) and the heat resistant resin (C), and the first polar solvent (Α1) and the second polar solvent. (Α2) depends on the solubility or the amount of use, but the mixing ratio is 6:4 to 9:1 from the viewpoint of the fluidity of the resin paste, the resolution of the resin film, the shape retention, and the surface balance. More preferably, it is 6.5: 3.5 to 8.5 to 1.5, preferably 7:3 to 8: 2 〇. In the resin paste of the present embodiment, the total resin is compared with the heat resistant resin (Β) and the heat resistant resin (C). The amount of the mixture is 100 parts by mass, preferably 100 to 3 parts by mass of a mixed solvent of the first polar solvent (Α1) and the second polar solvent (Α2), and more preferably 150 to 1000 parts by mass. The blending ratio of the heat-resistant resin (Β) and the heat-resistant resin (C) is not particularly limited, and may be any amount, but it is preferably adjusted to 10 to 30,000 with respect to 100 parts by mass of the total amount of the heat-resistant resin (Β). The heat-resistant resin (C) is preferably 10 to 200 parts by mass. When the amount of the heat-resistant resin (C) is 10 parts by mass or more, the thixotropy of the obtained heat-resistant resin paste tends to be increased, and if it is 300 parts by mass or less, the physical properties of the obtained resin film tend to be improved. The resin paste of the present invention has a viscosity at 25 ° C of 30 to 500 Pa·s, more preferably 50 to 400 Pa·s, from the viewpoints of the release property of the printing plate, the resolution of the resin film, and the shape retention property. It is better for 70~300 Pa. s -27- 201245312. When the viscosity at 25 °C is 30 Pa·s or more, the resolution of the resin film can be further improved, and when it is 500 Pa or less, the release property from the screen printing plate can be further improved. The viscosity can be controlled by adjusting the nonvolatile concentration (hereinafter referred to as NV) of the resin paste, the first polar solvent (A1), the heat resistant resin (B), or the molecular weight of the heat resistant resin (C). For example, the molecular weight of the heat resistant resin (B) and the heat resistant resin (C) is a weight average molecular weight measured by a gel permeation chromatograph in terms of standard polystyrene, and is preferably 10,000 to 100,000, preferably 20,000. 80000, preferably 30,000~60000. The thixotropy coefficient of the resin paste of the present embodiment is preferably from 2.0 to 10.0, more preferably from 2.0 to 6.0', still more preferably from 2.5 to 5.5, most preferably from 3.0 to 5.0. When the thixotropy coefficient is 2 or more, the printability can be further improved, and if it is 6.0 or less, the workability can be further improved. The resin paste of the present embodiment can be used for an insulating film such as a semiconductor device or an electrochemical device, in order to satisfy high heat resistance and insulation properties. Further, for example, by adding a decane coupling agent or the like, it is very useful as a binder for connecting a semiconductor device or the like. In the resin paste of the present embodiment, depending on the use, a low elastic coating material having rubber elasticity may be added. The type of the low-elastic dip material is not particularly limited, but examples thereof include an elastomer of an acrylic rubber, a fluororubber, a polyoxyethylene rubber, a butadiene rubber, or the like, or such a liquid rubber. Among these, in view of the heat resistance of the resin composition, it is preferably a polyoxymethylene rubber. Moreover, the surface of the coating material can be chemically modified with a functional group of an epoxy group, an amine group, an acryl group, a vinyl group, a phenyl group or the like, and preferably an epoxy group is modified by a -28-201245312. The addition of a low-elastic binder to the paste allows for low elasticity without impairing heat resistance and adhesion, and control of the modulus of elasticity is possible. The low elastic varnish having rubber elasticity is preferably micronized into a spherical shape or an amorphous shape, and has an average particle diameter of 0.1 to 6 μm, preferably 0.2 to 5 μm, more preferably 0.3 to 4 μm. When the average particle diameter is Ο.ΐμπι or more, the dispersibility tends to be improved, and when it is 6 μm or less, the flatness of the obtained coating film tends to be improved. The particle size distribution of the low elastic elastic material having rubber elasticity is 0.01 to 15 μm, preferably 0.02 to 15 μm, more preferably 0.03 to 15 μm. When the particle size distribution is Ο.ΟΙμηη or more, the dispersibility tends to be improved, and when it is 15 μm or less, the flatness of the obtained coating film tends to be improved. The heat resistant resin paste of the present embodiment has a low rubber elasticity. The blending amount of the elastic resin is preferably from 5 to 900 parts by mass, more preferably from 5 to 800 parts by mass, per 100 parts by mass of the total of the heat resistant resin (Β) and the heat resistant resin (C). In the resin paste of the present embodiment, an additive such as a colorant or a coupling agent or a resin modifier may be further added. As the colorant, carbon black, a dye, a pigment, or the like is exemplified. The coupling agent is exemplified by a coupling agent such as a decane system, a titanium system or an aluminum system, and the like is preferably a decane coupling agent. The decane coupling agent is not particularly limited, and for example, vinyl trichloroethane, vinyl methoxyethoxy ethoxy) decane, vinyl triethoxy decane, vinyl trimethoxy decane, r - A can be used. Acryloxypropyltrimethoxydecane, methacryloxypropylmethyldimethoxydecane, fluorene-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, shrinkage- 29- 201245312 Glyceroxypropyltrimethoxydecane, r-glycidoxypropylmethyldimethoxydecane, r-glycidoxypropylmethyldiethoxydecane, N- /3 ( Aminoethyl)r-aminopropyltrimethoxydecane, N-callo(aminoethyl)r-aminopropylmethyldimethoxydecane, r-aminopropyltriethoxydecane , N-phenyl·r-aminopropyltrimethoxydecane, 7-mercaptopropyltrimethoxydecane, r-mercaptopropyltriethoxydecane, 3-aminopropylmethyldiethyl Oxydecane, 3-ureidopropyltriethoxydecane, 3-ureidopropyltrimethoxydecane, 3-aminopropyltrimethoxydecane, 3-aminopropyl ginseng (2-methoxy) Ki-ethoxy-ethoxy) Decane, N-methyl-3-aminopropyltrimethoxydecane, triaminopropyltrimethoxydecane, 3,4,5-dihydroimidazol-1-yl-propyltrimethoxydecane, 3 -Methacryloxypropyltrimethoxydecane, 3-mercaptopropyl-methyldimethoxydecane, 3·chloropropyl-methyldimethoxydecane, 3-chloropropyl-di Methoxydecane, 3-cyanopropyl-triethoxydecane, hexylmethyldiazane, N,0-bis(trimethyldecyl)acetamide, methyltrimethoxydecane, A Triethoxy decane, ethyl trichloro decane, n-propyl trimethoxy decane, isobutyl trimethoxy decane, aluminum trichloro decane, octyl triethoxy decane, phenyl trimethoxy decane, benzene Triethoxy decane, methyl methacrylate (methacryloxyethoxy ethoxy) decane, methyl ginseng (glycidoxy) decane, N- / 3 (N-vinylbenzylaminoethyl) -γ-Aminopropyltrimethoxydecane, octadecyldimethyl[3-(trimethoxydecyl)propyl], r-chloropropylmethyldichlorodecane, r-chloro Propylmethyldimethoxydecane, Τ-chloropropylmethyldi Ethoxy decane, trimethyl decyl isocyanate, dimethyl decyl isocyanate, methyl decyl triisodecanoate, vinyl decyl triisocyanate, phenyl decyl triisocyanide-30-201245312 acid ester, As the tetraisocyanate decane or ethoxy decane isocyanate, one type or two or more types may be used. The titanium coupling agent is not particularly limited, and for example, isopropyl trioctyl decyl titanate, isopropyl dimethyl propylene isostearyl decyl titanate, isopropyl tri-dodecyl benzene sulfonate can be used. Titanium titanate, isopropylisostearyl decyldipropenyl titanate, isopropyl tris(dioctylphosphonate) titanate, isopropyltricumylphenyl titanate, isopropyl Ginseng (dioctyl pyrophosphate) titanate, isopropyl gin (η-aminoethyl) titanate, tetraisopropyl bis(dioctylphosphite) titanate, tetraoctyl double (di-tridecyl phosphite) titanate, tetrakis(2,2-diallyloxymethyl-1-butyl)bis(di-tridecyl)phosphite titanate, Dicumyl phenyloxyacetate titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, tetraisopropyl titanate, tetra-n-butyl titanate, butyl Titanate dimer, tetrakis(2-ethylhexyl) titanate, titanium acetylacetate, titanium polyacetate, titanium octanediol, ammonium titanium lactate, titanium lactate, titanium lactate, titanium Triethanol aluminate, polyhydroxy titanium stearate, four Raw titanate, tetraethyl orthotitanate, tetrapropyl orthotitanate, tetraisobutyl orthotitanate, stearyl titanate, tolyl titanate monomer, tolyl titanate polymer , diisopropoxy-bis(2,4-pentanedioic acid) titanium (IV), diisopropyl-bis-triethanolamine titanate, octanediol titanate, tetra-n-butoxytitanium polymerization , tri-n-butoxytitanium monostearate polymer, tri-n-butoxytitanium monostearate, etc., one of these may be used or two or more kinds of ruthenium may be used as the aluminum coupling agent. It is not particularly limited, and for example, ethyl acetoacetate aluminum diisopropylate, ginsyl (ethyl acetoacetate) aluminum, alkyl acetoacetic acid di-31 - 201245312 aluminum isopropoxide, monovinyl acetic acid bis (ethyl) can be used. Acetylacetate) aluminum, ginseng (acetonitrile) aluminum, aluminum = monoisopropoxy monooleyloxyethyl acetate, aluminum-di-n-butoxy-monoethylacetate acetate, aluminum - aluminum chelate compound such as diisobutoxy-monoethylacetate acetate, aluminum isopropoxide, mono-second butoxide aluminum diisopropanol ester, aluminum second butoxide, aluminum ethoxide, etc. Aluminum alkoxide, etc., can be used Merger of two or two or more. The amount of the above-mentioned additive is preferably 50 parts by mass or less based on 100 parts by mass of the total of the heat resistant resin (B) and the heat resistant resin (C). When the amount of the above additives is 50 parts by mass or less, the physical properties of the resin film such as heat resistance and mechanical strength tend to be improved. Next, a method of forming a resin film using the resin paste of the present embodiment and a obtained resin film will be described with reference to Fig. 1 . The method for forming a resin film according to the present embodiment includes the step of printing the resin paste of the above-described embodiment on a substrate web, and the step of heating the resin paste after screen printing at 1 to 450 °C. Fig. 1 is a cross-sectional view schematically showing a state of a resin film in each step in the method of forming a resin film of the embodiment. (a) Screen printing step The resin paste of the above-described embodiment is printed on the substrate 1 by screen printing. The resin paste is in a state in which the heat-resistant resin (C) 3 is dispersed in the solution 2 containing the first polar solvent (A1), the second polar solvent (A2), and the heat-resistant resin (B) at room temperature. The substrate 1 may be, for example, ruthenium or may form an emulsion layer on the surface of the substrate. The screen plate and the squeezing roller used in the screen printing substrate can be used without any particular limitation -32-201245312, but the coating of the resin paste of the present embodiment is suitable for a rubber-made squeezing roller" (b) the heating step will The resin paste after screen printing is heated at 100 to 450 °C. Heating can be carried out by a known method. In this step, the heat resistant resin (C) 3 is dissolved in the solution 2 containing the first polar solvent (A 1 ), the second polar solvent (A2), and the heat resistant resin (B), and then the 'second' polar solvent ( A2), the first polar solvent (A2) is sequentially volatilized to form a resin film 4. The heating temperature is preferably from 150 to 400 ° C, more preferably from 150 to 350 ° C. When the temperature is less than 100 ° C, the solvent is hard to volatilize, and the heat resistant resin (C) 3 is not dissolved in the solution 2 containing the first polar solvent (A 1 ), the second polar solvent (A2), and the heat resistant resin (B). There are many cases, and the surface flatness of the obtained resin film tends to be lowered. When heated at a temperature exceeding 450 ° C, there is a possibility that a hole is formed in the resin film 4 due to outgas. When at least one of the heat resistant resin (B) and the heat resistant resin (C) contains a polyimide precursor resin precursor, it is preferred to carry out the imidization at 350 ° C or higher, specifically 3 50~45 0 °C heating to harden the resin. When the temperature is less than 3 5 (the tendency of the ruthenium imidization reaction to slow down), the flatness of the resin film 4 is extremely high, and the surface roughness is 2 μm or less. Further, the surface roughness of the resin film in the present invention is Refers to the arithmetic mean roughness Ra. The arithmetic mean roughness Ra means that only the reference length (L) is extracted from the roughness curve in the mean line direction, and the average line direction of the extracted portion is set to the X axis, which is set in the longitudinal direction direction. For the Y-axis, when the thickness curve is expressed by y = f(x), the value obtained by the following formula is expressed in microns (μ«〇. That is, Ra is expressed by the following formula (1) -33-201245312数 [1] Λα==^Γΐ^ΙΛ ... π) The resin film 4 can be used for a semiconductor device or a solar cell, but from the viewpoint of the use state, the glass transition temperature Tg of the resin film is good. It is 18 (TC or more, preferably a thermal decomposition temperature of 300 ° C or more. The resin film 4 can be preferably applied because it has sputtering resistance, plating resistance, and alkali resistance required for the step of forming a rewiring step. In the semiconductor device, by using the resin film 4, it is also possible to reduce the amount of warpage of the germanium wafer, so that it is expected to increase half. The yield of the conductor device can be improved, and the productivity can be improved. In the semiconductor device, the resin paste of the embodiment can be screen-printed on a semiconductor substrate having a plurality of wirings having the same structure, and heated to form a resin film. A wiring electrically connected to the electrode on the semiconductor substrate is formed on the film, a protective film is formed on the wiring or the resin film, an external terminal is formed on the protective film, and is formed by dicing. The semiconductor substrate is not particularly limited. For example, the resin film 4 is preferably used for an insulating film or a protective film of a solar cell, and is particularly useful for a back contact type solar cell. For the back contact type structure, there are exemplified MWT structure (Metal Wrap Through), EWT structure (Emitter Wrap Through), and IBC structure (interdigital back contact type). Interdigitated -34- 201245312

Back contact), etc., because of the solar cell of the back electrode type, the positive electrode and the negative electrode are concentrated on the back surface of the light receiving surface for the purpose of improving the electric conversion efficiency, and the insulating film is required to exist. The insulating film or the protective film of the solar cell can be produced, for example, by forming a resin film on the substrate on which the plurality of positive electrodes and the negative electrode are formed in a dot shape, and printing the resin paste of the present embodiment by heating. . The solar cell substrate is not particularly limited, and examples thereof include a germanium wafer. Further, the resin paste of the present embodiment may be formed into a resin film by a coating method such as a cloth coating method or a press molding method. Fig. 2 is a plan view schematically showing a step of manufacturing the back electrode type solar cell of the MWT structure of the present embodiment, and Fig. 3 is a cross-sectional view schematically showing a step of manufacturing the back electrode type solar cell of the MWT structure of the embodiment. Fig. 3 is a schematic cross-sectional view taken along line A-B of Fig. 2. First, an aluminum wiring 1 2 is formed on the back surface 1 1 b of the germanium wafer 1 1 and has a plurality of positive electrodes 13 and negative electrodes 14 formed at specific intervals (refer to FIGS. 2 and 3 (a). )). Here, the positive electrode 13 is formed on the back surface Πb of the 矽 wafer 1 1 , and the negative electrode 14 is formed so as to penetrate from the light receiving surface 11 a of the 矽 wafer 1 1 to the back surface lib. Further, the negative electrode 14 is not in contact with the aluminum wiring 12, and a gap is left between the negative electrode 14 and the aluminum wiring 12. On the other hand, the positive electrode 13 is not in contact with the aluminum wiring 12. Then, the resin paste is screen-printed on the aluminum wiring 12 so that the end portion of the negative electrode 14 is exposed, and the resin film 4 is formed by heating (refer to Figs. 2 and 3(b)). The resin film 4 is filled between the aluminum wiring 1 2 and the negative electrode 14 . Subsequently, a portion of the resin film 4 is coated, and the negative electrode 14 and the positive electrode 13 are formed -35-201245312

Tab wiring 15 (refer to FIG. 2 and FIG. 3(c)). Since the Tab wiring 15 formed on the negative electrode 14 is present in the resin film 4, it does not contact the aluminum wiring 12 on the positive electrode 13 side, and electron loss does not occur between the electrodes. The positive electrode 13 and the negative electrode 14 are preferably formed of a material mainly containing silver. Fig. 4 (a) is a plan view schematically showing an example of a back electrode type solar cell having an IBC structure according to the present embodiment, and Fig. 4 (b) is a view schematically showing a cross section between CD lines in Fig. 4 (a). The back electrode type solar cell 30 of the ibc structure shown in FIG. 4 is composed of a tantalum wafer 21 having a light receiving surface 21a and a back surface 21b, and a plurality of positive electrodes 23 and negative electrodes 24 formed at specific intervals on the back surface 21b to make a positive electrode. 23 and the end portion of the negative electrode 24 are exposed so as to be covered with the resin film 5 of the wafer 21. In the germanium wafer 21, the portion in contact with the positive electrode 23 is the P layer 27, and the other portion is the n layer 26. Further, the resin film 5 can be formed by the same method as the resin film 4 in the back electrode type solar cell of the above MWT structure. Fig. 5 (a) is a plan view schematically showing an example of a back electrode type solar cell of the EWT structure of the present embodiment, and Fig. 5 (b) is a view schematically showing a cross section taken along line E-F of Fig. 5 (a). The back electrode type solar cell 40 of the EWT structure shown in FIG. 5 is composed of a tantalum wafer 31 having a light receiving surface 31a and a back surface 3 1 b, and a plurality of positive electrodes 33 formed at a specific interval on the back surface 3 1 b and The negative electrode 34 is formed by covering the resin film 6 of the wafer 31 so that the ends of the positive electrode 33 and the negative electrode 34 are exposed. In the germanium wafer 31, a portion of the upper portion where the negative electrode 34 is formed is provided with a through hole 36 facing the light receiving surface 31a. Further, the resin film 6 - 36 - 201245312 can be formed by the same method as the back electrode type lipid film 4 of the above MWT structure. Fig. 6 is a view showing a resin film printed by screen printing. First, a substrate 45 to be printed, a mesh screen 42 on which the emulsion 41 is placed, and a rubber squeeze roller 44 for moving the solid in the printing direction A (the roller 44 is moved in the screen A along the printing direction A) The resin paste 43 is applied to the mesh of part 4 of the machine, and the coated resin paste 43 is heated to form a film (Fig. 6(c)). Further, in the back surface of the back electrode type solar cell, the emulsion is applied to the back surface of the mesh in which the resin is not applied to the portion where the resin is applied to the portion of the solar cell. The resin paste of the embodiment is difficult to crack due to the flatness. And the reliability is also excellent. And compared with the trace, the resin after drying is prevented from being electrically conductive from the thinnest portion of the insulating film due to high flatness, and the resin film having electrical properties is preferably dried in a film thickness of 1 to ΙΟΟμπι, preferably at 1 to ΙΟμηι. Inside. If the flatness is poor, cracking is likely to occur, and no power generation effect is obtained. Further, the net thickness of the concave portion of the resin film surface of the resin film is caused to be electrically conductive, and the electrical property is lowered. The resin film of the present embodiment has a surface of 0.2 or less, more preferably Ο.ΐμπι or less. !In the solar cell, a method of manufacturing the resin is applied to a specific portion of the back surface of the resin paste 43 6(a)). The rubber is extruded, and the resin film 46 is obtained by passing through the uncoated emulsion substrate 45 (Fig. 6(b)). (When the resin paste is applied to the surface, the paste may be applied in a corresponding manner. In the case of sheet printing, the film thickness of the web film is uniform and excellent. In the present embodiment, it is more preferable that the thickness of the self-tree is low in the case of the conductive unevenness between the electrodes in the 1 to 20 μm method. The thickness Ra of the S is preferably -37. - 201245312 EXAMPLES Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto. Further, in the present embodiment, the gel permeation chromatography apparatus was carried out under the following conditions: Dissolution liquid: ΝΜΡ, Η3ΡΟ4 ( 0·06 Moor/L)

Column type: Shodex solvent-substituted separation column made by Showa Denko Co., Ltd. GPC KD-806M Standard material for calibration line preparation: Standard polystyrene < Synthesis Example 1: Synthesis of heat-resistant resin (B) > A 5 liter, 4-necked flask equipped with a thermometer, a stirrer, a nitrogen gas introduction tube, and a cooling tube with an oil-water separator was fed with 2,2-bis[4-(4-aminophenoxy)phenyl group under a nitrogen stream. Propane (hereinafter referred to as BAPP) 650.90g (1.59 mole) 'Add N-methyl-2-indole (hereinafter referred to as NMP) 3609.86g and dissolve. Then, 384.36 g (1.83 mol) of trimellitic anhydride (hereinafter referred to as TAC) was added while cooling so as not to exceed 2 °C. After stirring at room temperature for 1 hour, 215.90 g (2.14 mol) of triethylamine (hereinafter referred to as TEA) was added while cooling at a temperature of not more than 20 ° C, and reacted at room temperature for 1 hour to produce a polyamidite paint. material. The obtained polyamic acid lacquer was further subjected to a dehydration reaction at 180 ° C for 6 hours to produce a polyamide amidoxime paint. The precipitate obtained by injecting the polyamidamine imide into water is separated, pulverized, and dried to obtain a polyamidamine resin powder (MPAI-1) (in the formula (1), X is a formula (a) shows a polyamidimide). The weight average molecular weight of the obtained polyamidoxime-38-201245312 imine resin (mpai-1) was 55,000 as measured by a gel permeation chromatography (hereinafter referred to as GPC) in terms of standard polystyrene. Moreover, the mass ratio of the first polar solvent (A1) and the second polar solvent (A2) in the later-described experiment of the polyamidoximine resin powder (MPAI-1) at 25 ° C is 7:3 or 9 The solution of :1 is soluble. <Synthesis Example 2: Synthesis of heat-resistant resin (C)> In a 1-liter four-necked flask equipped with a thermometer, a stirrer, a nitrogen gas introduction tube, and a cooling water tube with an oil-water separator, BAPP 69.72 was fed under a nitrogen stream. g (170.1 mmol), NMP 693.52g was added and dissolved. Then, TAC 2 5.0 5 g (11 9.0 mmol) and 3,4,3',4'-benzophenone tetracarboxylic dianhydride (hereinafter referred to as BTDA) were added while cooling not to exceed 20 °C. ) 2 5.47g (79.1 millimoles). After stirring at room temperature for 1 hour, 14.43 g (142.8 mmol) of TEA was added while cooling at not more than 20 ° C, and the mixture was reacted at room temperature for 1 hour to produce a polyamic acid paint. The obtained polyamic acid lacquer was further subjected to a dehydration reaction for 18 hours at TC to produce a polyimide pigment paint. The precipitate obtained by injecting the polyimide pigment into water was separated, pulverized, and dried. The weight average molecular weight of the polyimine resin (PAI-1) obtained by obtaining the polyimine resin powder (PAI-1) (wherein X is a polyimine represented by the formula (a)) The GPC was measured to be 3 9000 in terms of standard polystyrene conversion. Further, the polyimine resin powder (PAI-1) was soluble at 25 ° C in the first polar solvent (A1) in the experiment described later. However, it is insoluble in the second polar solvent (A2), and is insoluble in the solution of the first polar solvent (A1) and the second polar solvent (A2) in a mass ratio of 7:3 to 39-201245312 or 9:1. Further, the average particle diameter is 1 μm. <Preparation of resin paste (Ρ-1) to (Ρ-7)> (Example 1) After mounting a thermometer, a stirrer, a nitrogen gas introduction tube, and a cooling tube. In a 4-necked flask, 92.4 g of r-butyrolactone as a first polar solvent (Α1) and diethylene glycol diethyl ether as a second polar solvent (Α2) were added under a nitrogen stream. 39.6 g, 30.8 g of the polyamidoximine resin powder (MPAI-1) obtained in Synthesis Example 1 as the heat resistant resin (B), and the polysiloxane obtained as the heat resistant resin (C) in Synthesis Example 2. 13.2 g of an amine resin powder (PAI-1), and the temperature was raised to 180 ° C while stirring. After stirring at 180 ° C for 2 hours, the heating was stopped, and the mixture was cooled while stirring to obtain a yellow composition. The filter was applied to the filter KST-47. (ADVANTECH Co., Ltd.) was inserted into a piston made of polyoxyethylene rubber, and filtered under pressure at a pressure of 3.0 kg/cm 2 to obtain a resin paste (P-1). (Example 2) In addition to the use of cellosolve acetate A resin paste (P-2) was obtained in the same manner as in Example 1 except for the second polar solvent (A2). (Example 3) In addition to using r-butyrolactone 118.9 g as the first polar solvent (A1), diethyl A resin paste (P-3) was obtained in the same manner as in Example 1 except that 13.2 g of diol diethyl ether was used as the second polar solvent (A2). -40 - 201245312 (Example 4) Except that the cellosolve acetate was used as the first In the same manner as in Example 3 except for the dipolar solvent (A2), a resin paste (p_4) was obtained. (Comparative Example 1) Diethylene glycol dimethyl ether was substituted for diethylene glycol. In the same manner as in Example 1, except for dimethyl ether, a resin paste (P_5) was obtained (Comparative Example 2) except that 66.1 g of r-butyrolactone was used as the first polar solvent (A1), diethylene glycol diethyl ether 6 6 · A resin paste (P-6) was obtained in the same manner as in Example 1 except that 1 g was used as the second polar solvent (A2). (Comparative Example 3) In addition to using 7-butyrolactone 66.lg as the first polar solvent (A1) A resin paste (P-7) was obtained in the same manner as in Example 1 except that the cellosolve acetate 66 was used as the second polar solvent (A2). <Evaluation> (Viscosity and Thix Coefficient (TI値)) The viscosity and thixotropic coefficient (TI値) of the resin pastes obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were made by using a high viscosity viscometer RE- 80U (East Machinery Industry Co., Ltd.) measurement. The viscosity was measured at a rotation number of 0 · 5 rpm, and the thixotropy coefficient (TI 値) was calculated as the ratio of the viscosity measured at a rotation number of 丨0 rpm to the viscosity measured at a rotation number of -41 - 201245312 1 rpm. (Non-volatile content) The resin pastes obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were weighed several gram on a metal disk. The resin paste was dried at 150 ° C for 1 hour, dried at 250 ° C for 2 hours, and weighed on a metal disk, and the concentration of non-volatile matter (hereinafter referred to as NV) was calculated based on the following formula (2). NV (%) = (mass after heating and drying of resin paste (g) / mass of resin paste before heating and drying (g)) xl 〇〇 (2) (resolution) on 8 吋 sand wafer, coated with diameter The emulsion of the circular opening of 300 μm or 500 μηι, the resin paste obtained in Examples 1 to 4 and Comparative Examples 1 to 3, using a screen printing machine (EURONG Precision Industry Co., Ltd., LZ-0843 with alignment device) ), screen (NBC MESHTEC, V380, wire diameter 23μηι, thickness 43μηι, emulsion thickness 2 Ομπι) and ΜΝ rubber extrusion roller (EURONG Precision Industry Co., Ltd.), the stencil is left in such a manner as to leave the opening print. After screen printing, it is heated on a hot plate heated to 1 ° C for 1 , minutes, and then heated in an oven heated to 25 ° C for 30 minutes. For the dried and hardened resin film, a universal projection is used. The machine (manufactured by NIKON Co., Ltd., V-1 2B) measures the average enthalpy of the diameter (pore diameter) of the pores at six locations in the printing portion of the resin paste corresponding to the opening of the emulsion. Examples 1, 2 and Comparative Examples - 42 - 201245312 The hole portions of the first and third portions were formed into an emulsion opening portion having a diameter of 30 μm. Further, the hole portions of Examples 3 and 4 were formed into an emulsion opening portion having a diameter of 5 μm. Further, the deviation indicates the standard deviation of the observed portion (η = 6), and the smaller the better. Specifically, the aperture of the printing unit was observed by the universal projector, and the hole diameter was calculated by a three-point input method using a data processing system (NIKON, DP-202). The average 値 of the aperture of n = 6 is taken as the resolution. (Dry film thickness) For the resin film produced in the evaluation of the resolution, a dry film thickness was measured using a micrometer (MITUTOYO, model MDE-25PJ). (Surface thickness) After the screen printing, the resin film obtained by heating as described above is measured using a stylus type surface roughness measuring instrument (manufactured by Kojima Seisakusho Co., Ltd., model: SE 1 700-1 8 D) :1 (]· 〇mm, feed rate: 0.5 mm / s) 'Measurement of surface roughness of resin film (arithmetic mean roughness: Ra) » Resin paste obtained in Examples 1 to 4 and Comparative Examples 1 to 3 ( The type, the boiling point, the first polar solvent (A 1 ), and the second polar solvent (A2) of the first polar solvent (A1) and the second polar solvent (A2) contained in P-1) to (P-7) The mass ratio, the resin pastes (P-1) to (P-7), and the evaluation results of the resin films obtained by using the above were shown in Tables 1 and 2. Further, the resin paste obtained in Comparative Example 2 was in the form of a chewing gum. Unable to measure viscosity and TI値' can't be screen printed. -43- 201245312 [Table i] Real _ 1 2 3 4 A1 Type 7-butyrolactone r-butyrolactone r-butyrolactone r-butyrolactone Boiling point (°c) 204 204 204 204 A2 Species Diethylene glycol dimethyl ether butyl ketone Cellulose acetate Diethylene glycol dimethyl ether Butyl solvate Cellulose acetate Boiling point (°c) 185 171 185 171 Mass ratio of A1 to A2 7:3 7:3 9:1 9:1 Viscosity (Pa · s) 93 105 87 99 ΤΙ値 4.0 4.0 3.3 3.8 NV (°/〇) 21.9 20.8 22.2 21.3 Resolution (μηι) 142 176 320 421 Deviation number 18 22 19 30 Dry film thickness (μ m) 4 4 4 4 Surface roughness Ra(Mm) 0.0885 0.0465 0.0287 0.0185 [Table 2] Comparative Example 1 2 3 A1 Type r-butyrolactone r-butyl Lactone 7"-butyrolactone boiling point (°c) 204 204 204 A2 type triethylene glycol dimethyl ether diethylene glycol dimethyl ether butyl hydrazine cellosolve acetate boiling point (°C) 216 185 171 A1 and A2 Mass ratio 7:3 5:5 5:5 Viscosity (Pa _ s) 102 _ 102 ΤΙ値3.6 3.6 NV (%) 20.9 _ 23.1 Resolution (μιη) 167 162 Deviation number 28 26 Dry film thickness (μ m) 4 • 5 surface roughness Ra^m) 0.1444 • 0.2049 -44- 201245312 It can be seen from Tables 1 and 2 that the resin film obtained from the resin pastes obtained in Examples 1 to 4 is compared with the use of the boiling point temperature ratio of the first polar solvent. (A 1 ) The resin film obtained by the resin sample obtained in Comparative Example 1 of the second polar solvent (A2) or the resin paste of Comparative Examples 2 and 3 in which the ratio of A1 : A2 is 5.5 can obtain a precise resolution. Particularly excellent surface flatness. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a resin paste immediately after screen printing on a substrate, and FIG. 1(b) is a schematic cross-sectional view of a resin film obtained by heating a resin paste on a substrate. . Fig. 2 is a plan view schematically showing a step of producing a back electrode type solar cell of the MWT structure of the present embodiment. Fig. 3 is a cross-sectional view schematically showing the steps of manufacturing the back electrode type solar cell of the MWT structure of the present embodiment. Fig. 4 (a) is a plan view schematically showing an example of a back electrode type solar cell having an IBC structure according to the present embodiment, and Fig. 4 (b) is a view showing an example of a back electrode type solar cell having an IB C structure according to the present embodiment. Sectional view. Fig. 5 (a) is a plan view schematically showing an example of a back electrode type solar cell of the EWT structure of the present embodiment, and Fig. 5 (b) is a view schematically showing an example of a back electrode type solar cell of the EWT structure of the embodiment. Sectional view. 6 is a schematic view showing a method of manufacturing a resin film printed by screen printing. -45-201245312 [Key element symbol description] 1 : Substrate 2: a first polar solvent (A1), a second polar solvent (A2), and Solution 3 of heat resistant resin (B): heat resistant resin (C) 4, 5, 6 : Resin film 1 1 , 2 1, 3 1 : 矽 wafer 1 2 : Ming wiring 1 3, 23, 3 3 : positive Electrode 14, 24, 34: Negative electrode 15: TAB wiring 20: Substrate 30: Back electrode type solar cell of IBC structure 3 6 : Through hole 40: Back electrode type solar cell of EWT structure 4 1 : Emulsion 42 : Screen 43 : Resin paste 44 : Rubber squeeze roll 45 : Substrate 46 : Resin film - 46 -

Claims (1)

201245312 VII. Patent application scope: 1. A resin paste comprising: a first polar solvent (A 1 ) and a boiling point of the first polar solvent (A 1 ) at a mass ratio of 6:4 to 9:1; a mixed solvent of a second polar solvent (A2) having a low boiling point, a heat resistant resin (B) soluble in the above mixed solvent at room temperature, soluble in the first polar solvent (A1) at room temperature but insoluble in The second polar solvent (A2) is insoluble in the heat-resistant resin (C) of the mixed solvent, and the heat-resistant resin (C) is dispersed in a solution containing the mixed solvent and the heat-resistant resin (B). 2. The resin paste of claim 1, wherein a difference between a boiling point of the first polar solvent (A1) and a boiling point of the second polar solvent (A2) is 1 〇 to 1 〇 (TC 〇 3. as in claim 1 or a resin paste according to 2, wherein the heat resistant resin (B) and the heat resistant resin (C) are each independently selected from the group consisting of a polyamide resin, a polyimide resin, a polyamide resin, or a polyruthenium. The resin paste according to any one of claims 1 to 3, wherein the aforementioned heat-resistant resin (C) dispersed in the solution is an average particle. A method of producing a solar cell having a diameter of 50 μm or less. 5. A method for producing a solar cell, comprising the steps of: printing a resin paste screen according to any one of claims 1 to 4 on a substrate having a negative electrode and a positive electrode; The step on the side of the electrode of the material, -47-201245312, the step of heating and drying the previously printed resin paste by screen printing at 100 to 450 ° C. 6. A solar cell by the method of claim 5 Method and manufacturer. 7. A resin film, which comprises the following steps Formed by a method of the method, and having a surface roughness of 2 μm or less; the step of printing the resin paste stencil on the substrate according to any one of claims 1 to 4, and heating the stencil at 100 to 450 ° C A step of printing the aforementioned resin paste. A semiconductor device comprising the resin film of claim 7. -48 -