TWI699344B - Conductive paste for solar cell's electrode and solar cell using the same - Google Patents

Abstract

The present invention relates to a conductive paste for solar cell electrodes, which comprises metal powder, glass frit and organic carrier, and the surface of the glass frit is coated with an aliphatic amine compound. The aliphatic amine compound can be used to coat the surface of the glass frit to improve its dispersibility, and the power generation efficiency of the solar cell can be improved by improving the electrical characteristics of the solar cell electrode formed by the conductive paste.

Description

Conductive paste for solar cell electrode and solar cell using the same

The present invention relates to a conductive paste for forming electrodes of solar cells and solar cells using the same.

A solar cell is a semiconductor element used to convert solar energy into electrical energy, usually in the form of a p-n junction, and its basic structure is the same as a diode. Fig. 1 shows the structure of a general solar cell element. The solar cell element is usually composed of a p-type silicon semiconductor substrate 10 with a thickness of 180 to 250 ㎛. On the light-receiving surface side of the p-type silicon semiconductor substrate 10, an n-type doped layer 20 with a thickness of 0.3 to 0.6 ㎛, an anti-reflection film 30 and a front electrode 100 are formed thereon. In addition, a back aluminum electrode 50 is formed on the back side of the p-type silicon semiconductor substrate 10.

The front electrode 100 is a conductive paste obtained by mixing conductive silver powder, glass frit, organic vehicle, and additives on the anti-reflection film 30. The back electrode 50 is formed by sintering, and the back electrode 50 is an aluminum paste composition composed of aluminum powder, glass frit, organic vehicle, and additives, which is coated and dried by screen printing, etc., at 660°C (melting point of aluminum) The above temperature is formed by sintering. During the above-mentioned sintering process, aluminum will be diffused into the p-type silicon semiconductor substrate 10, thereby forming an Al-Si alloy layer between the back aluminum electrode 50 and the p-type silicon semiconductor substrate 10. Layer to form a p+ layer 40. The p+ layer 40 as described above can prevent the recombination of electrons and achieve a BSF (Back Surface Field) effect that can improve the collection efficiency of generated carriers. In the lower part of the back aluminum electrode 50, a back silver electrode 60 can also be provided.

In addition, the glass frit is a necessary composition to realize the Ag/Si contact of silicon solar cells. In order to achieve high-efficiency solar cells, glass frit with excellent contact resistance (Rc) must be used. At present, the method of controlling the etching of the anti-reflection film by adjusting the composition system, particle size or content of the glass frit is mainly used, but this will cause many problems in the dispersion of the glass frit. And by observing the image after sintering, it can be found that because the thickness of the glass layer is not uniform, it will cause n-layer damage in the thicker area, and in the thinner area, the silver powder will penetrate less. The problem that causes the current to decrease or the resistance to increase occurs.

(Patent Document 1) U.S. Registered Patent No. 8,748,327 B1 (2014.06.10.) (Patent Document 2) WO Publication Patent No. 2013/105812 A1 (2013.07.18.) (Patent Document 3) U.S. Publication Patent No. 2011-0094578 A1 (2011.04.28.)

The object of the present invention is to improve the dispersibility by coating the surface of the glass frit in the conductive paste composition for solar cell electrodes with aliphatic amine compounds, and to improve the solar energy formed by the conductive paste. The electrical characteristics of battery electrodes improve the power generation efficiency of solar cells.

However, the purpose of the present invention is not limited to the above-mentioned purpose, and those with ordinary knowledge in the technical field will be able to further clearly understand other purposes not mentioned by the following description.

The present invention provides a conductive paste for solar cell electrodes, which comprises metal powder, glass frit and organic carrier, and the surface of the glass frit is coated with an aliphatic amine compound.

In addition, in the present invention, the aliphatic amine compound contains an alkylamine substance having 6 to 24 carbon atoms.

In addition, in the present invention, the above-mentioned alkylamine substances include triethylamine, heptylamine, octadecylamine, hexadecylamine, decylamine, and octylamine ( Octylamine), Didecylamine (Didecylamine) or Trioctylamine (Trioctylamine).

In addition, in the present invention, the thickness of the coating layer formed by the above-mentioned aliphatic amine compound coating treatment is 0.1 nm to 50 nm.

In addition, in the present invention, the glass frit is a first glass frit, the conductive paste further includes a second glass frit, and the surface of the second glass frit is not coated or coated with fatty acid.

In addition, in the present invention, the above-mentioned fatty acid includes lauric acid, oleic acid, stearic acid, palmitic acid, or acetic acid.

In addition, the present invention provides a solar cell in which a front electrode is provided on the upper part of a substrate and a back electrode is provided on the lower part of the substrate. The front electrode is obtained by coating the conductive paste for solar cell electrodes. It is manufactured by drying and sintering.

In order to improve the dispersibility, the conductive paste of the present invention includes a glass frit coated with an aliphatic amine compound, so that the glass frit can be uniformly coated when forming an electrode. In this way, the reactivity during sintering can be optimized, especially the damage of the n-layer at high temperature can be minimized, the adhesive force can be improved and the open circuit voltage can be optimized. In addition, the metal powder (such as silver powder) can be uniformly penetrated during sintering, thereby reducing the contact resistance between the electrode and the n layer. Finally, the power generation efficiency of the solar cell can be improved by improving the electrical characteristics of the solar cell electrode.

Before describing the present invention in detail, it should be understood that the terms used in this specification are only for describing specific embodiments, and the scope of the present invention is not limited by the terms used. The scope of the present invention The definition should be made only by the scope of the attached patent application. Unless explicitly stated otherwise, the meanings of all technical and scientific terms used in this specification are the same as those commonly understood by those with ordinary knowledge.

Throughout this specification and the scope of the patent application, unless expressly stated otherwise, the term "comprise (comprise, comprises, comprising)" means to include the mentioned objects, steps, or a series of objects and steps, but does not mean Exclude the possibility of any other objects, steps, or series of objects or series of steps.

In addition, unless otherwise explicitly stated to the contrary, each embodiment of the present invention can be combined with certain other embodiments. In particular, a certain feature described as preferable or advantageous can also be combined with another certain feature and certain characteristics described as preferable or advantageous. Next, the embodiments of the present invention and related effects will be described in conjunction with the drawings.

The slurry of an embodiment of the present invention is suitable for use in forming solar cell electrodes, and provides a conductive slurry containing glass frit coated with an aliphatic amine compound. Specifically, the conductive paste of the present invention contains metal powder, glass frit, organic vehicle and other additives.

As the metal powder, silver powder, through powder, nickel powder, aluminum powder, etc. can be used. When it is applied to the front electrode, silver powder is mainly used, and when it is applied to the back electrode, aluminum powder is mainly used. As the metal powder, one of the foregoing powders can be used alone, or an alloy of the foregoing metals can be used, or a mixed powder obtained by mixing at least two of the foregoing powders can be used.

In consideration of the thickness of the electrode formed during printing and the linear resistance of the electrode, the content of the metal powder is preferably 40 to 95% by weight based on the total weight of the conductive paste composition. When the content is less than 40% by weight, the specific resistance of the formed electrode may be too high, and when the content is greater than 98% by weight, the metal powder may not be uniformly dispersed due to insufficient content of other components. . Preferably, it contains 70 to 90% by weight.

When a conductive paste containing silver powder is used to form the front electrode of a solar cell, it is advisable to use pure silver powder as the silver powder. In addition, it is also possible to use silver-plated composite powder or silver-plated composite powder whose surface is at least composed of a silver layer. Alloy etc. as the main component. In addition, other metal powders can also be mixed for use. For example, aluminum, gold, palladium, copper, or nickel can be used.

The average particle size (D50) of the metal powder can be 0.1 to 10㎛, but in consideration of the ease of slurrying and the density during sintering, it is preferably 0.5 to 5㎛. The shape can be spherical, At least one of needle shape, plate shape, and non-specific shape. The metal powder can also be used by mixing two or more types of powders having different average particle diameters, fineness distributions, and shapes.

In order to improve the dispersibility of the glass frit, it can be coated with an aliphatic amine compound. Preferably, the aliphatic amine compound can contain an alkylamine substance having 6 to 24 carbon atoms. More preferably, the surface of the glass frit can be coated with an alkylamine substance having 10 to 20 carbon atoms. For example, the above-mentioned alkylamine substances can include triethylamine, heptylamine, octadecylamine, hexadecylamine, decylamine, octylamine, and two Didecylamine or Trioctylamine.

The above aliphatic amine compound is preferably coated on the surface of the glass frit to a thickness of 0.5 nm to 50 nm. The coating process of the aliphatic amine compound can be performed by a method of adding a glass frit into an organic solvent or an aqueous solution in which the aliphatic amine compound is dissolved, stirring for a certain period of time, and then filtering. When the thickness of the coating formed by the above-mentioned aliphatic amine compound coating treatment is less than 0.5nm, it may lead to a decrease in the dispersibility improvement effect of the glass frit, and when the thickness of the coating is greater than 50nm, it may This may cause a decrease in the electrical characteristics of the solar cell electrode formed using the conductive paste containing the above-mentioned glass frit. The thickness of the coating can be adjusted by the content of the aliphatic amine compound used in the coating process.

The composition, particle size, and shape of the above-mentioned glass frit are not particularly limited. Not only can use lead-containing glass frit, but also lead-free glass frit. Preferably, as the composition and content of the glass frit, the oxide conversion standard contains 5-29 mol% PbO, 20-34 mol% TeO ₂ , 3-20 mol% Bi ₂ O ₃ , and 20 mol% The following SiO ₂ , 10 mol% or less B ₂ O ₃ , 10 to 20 mol% alkali metals (Li, Na, K, etc.) and alkaline earth metals (Ca, Mg, etc.) are suitable. By combining the organic content of the above-mentioned components, the line width of the electrode can be prevented from increasing, the contact resistance characteristic in the high surface resistance can be optimized, and the short circuit current characteristic can be optimized.

The average particle size of the glass frit is not limited, and can be in the range of 0.5 to 10㎛, and various particles with different average particle sizes can be mixed and used. Preferably, the average particle size (D50) of the at least one glass frit used is 2 ㎛ or more and 10 ㎛ or less.

The content of the glass frit is preferably 1 to 10% by weight based on the total weight of the conductive paste composition. When the content is less than 1% by weight, the electrical specific resistance may be too high due to incomplete sintering, and When the content is greater than 10% by weight, too much glass content in the sintered body of the metal powder may also cause the problem of too high electrical specific resistance.

By applying the aliphatic amine compound to the surface of the glass frit as described above, uniform coating of the glass frit can be achieved when forming the electrode. In this way, the reactivity during sintering can be optimized, especially the damage of the n-layer at high temperature can be minimized, the adhesive force can also be improved and the open circuit voltage (Voc) can be optimized. In addition, the metal powder (such as silver powder) can be uniformly penetrated during sintering, thereby reducing the contact resistance between the electrode and the n layer. With the above-mentioned effects, the effect of easily adjusting the composition, particle size, or shape of the glass frit can be further achieved.

As another embodiment of the present invention, the glass frit can include a first glass frit coated with a substance having 6 to 24 carbon atoms and a second glass frit coated with a fatty acid. The first glass frit and the second glass frit can respectively include the lead-containing glass frit or the lead-free glass frit as described above. In addition, alkylamines include Triethylamine, Heptylamine, Octadecylamine, Hexadecylamine, Decylamine, Octylamine, Didecylamine Didecylamine or Trioctylamine, fatty acids can include lauric acid, oleic acid, stearic acid, palmitic acid and acetic acid. By mixing the first glass frit and the second glass frit coated with different types of substances as a glass frit, the dispersion of the glass frit in the conductive paste can be easily adjusted.

As another embodiment of the present invention, the first glass frit can be a glass frit that has been coated with the alkylamine substance, and the second glass frit can be a glass frit that has not been coated.

The above-mentioned organic vehicle is not limited, and can contain an organic binder and a solvent, and sometimes the solvent can be omitted. The content of the organic vehicle is not limited, but preferably contains 1 to 30% by weight based on the total weight of the conductive paste composition.

For organic vehicles, it is required to have the characteristics of maintaining a uniform mixing state of metal powder and glass frit. For example, when the conductive paste is coated on the substrate by screen printing, the homogenization of the conductive paste should be achieved , So as to suppress the blur and flow of the printed pattern, and at the same time should be able to improve the flow of conductive paste from the screen printing plate and the separation of the printing plate.

The organic binder contained in the organic carrier is not limited. Examples of cellulose ester compounds include cellulose acetate and cellulose acetate butyrate, and examples of cellulose ether compounds include ethyl cellulose and methyl cellulose. , Hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose and hydroxyethyl methyl cellulose, etc. Examples of acrylic compounds include polyacrylamide, polymethacrylate, polymethyl Methyl acrylate and polyethyl methacrylate, etc. Examples of ethylene include polyvinyl butyral, polyvinyl acetate, polyvinyl alcohol, and the like. At least one selected from the above-mentioned organic adhesives can be used.

The solvent used to dilute the composition is selected from α-terpineol, dodecyl alcohol ester, dioctyl phthalate, dibutyl phthalate, cyclohexane, hexane, toluene, Compounds composed of benzyl alcohol, dioxane, diethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether and ethylene glycol monobutyl ether acetate At least one of them is preferably used.

The conductive paste composition of the present invention can also contain known additives, such as dispersants, plasticizers, viscosity modifiers, surfactants, oxidants, metal oxides, and metal organic compounds, as needed.

The conductive paste composition for solar cell electrodes as described above can be produced by mixing and dispersing metal powder, coated glass frit, organic vehicle, additives, etc., and then filtering and degassing.

The present invention provides a method for forming an electrode of a solar cell by coating the above-mentioned conductive paste on a substrate, drying and sintering it, and a solar cell electrode manufactured by the above-mentioned method. In the method for forming the electrode of the solar cell of the present invention, in addition to using the conductive paste containing the coated glass frit, the substrate, printing, drying, and sintering can use those commonly used in the manufacture of solar cells. method. As an example, the aforementioned substrate can be a silicon wafer.

In addition, because the electromotive force of the solar cell including the solar cell electrode formed by the above-mentioned method is low, it is necessary to connect a plurality of solar cell cells to form a solar cell module with appropriate electromotive force (Photovoltaic Module). ) To use, at this time, each solar cell unit will be connected by lead-plated ribbon wires of a specific length.

In addition, the conductive paste of the present invention can also be applied to crystalline solar cells (P-type, N-type), PESC (Passivated Emitter Solar Cell), PERC (Passivated Emitter and Rear Cell, passivation Emitter and back electrode solar cells), PERL (Passivated Emitter Rear Locally Diffused, passive emitter rear locally diffused solar cells) and other structures, as well as double printing, dual printing and other changed printing projects.

Manufacturing example 1

After adding a Pb-Te-Bi type glass frit to a 0.3% concentration organic solution made by dissolving octadecylamine (ODA) in ethanol, a ball mill (Ball-mill) was used at room temperature. ) The treatment was carried out at 80 rpm for 24 hours. Next, a drying operation was performed in an oven at 50° C. for 1 hour to obtain a glass frit coated with octadecylamine.

Manufacturing example 2

Compared to Production Example 1, except that Duomeen TDO (common name: N-(Tallow alkyl)-1,3-propanediamine oleates, tallow diamine dioleates) was dissolved in ethanol to produce a 0.3% concentration of organic Except for the solution, a glass frit subjected to TDO coating treatment was obtained by the same method as the above-mentioned Production Example 1.

Manufacturing example 3

With respect to the above-mentioned production example 1, except that a 0.3% concentration organic solution was produced by dissolving stearic acid in ethanol, the stearic acid-coated solution was obtained by the same method as the above-mentioned production example 1. Processed glass frits.

Manufacturing example 4

With respect to the above-mentioned production example 1, except that oleic acid (oleic acid) was dissolved in ethanol to produce a 0.3% concentration organic solution, the same method as the above-mentioned production example 1 was used to obtain the oleic acid-coated Glass frit.

Manufacturing example 5

With respect to the above-mentioned production example 1, except that an organic solution with a concentration of 0.1% was produced by dissolving octadecylamine in ethanol, the same method as in the above-mentioned production example 1 was used to obtain a glass melt coated with octadecylamine. Piece.

Manufacturing example 6

With respect to the above-mentioned production example 1, except that an organic solution with a concentration of 0.5% was produced by dissolving octadecylamine in ethanol, the same method as the above-mentioned production example 1 was used to obtain a glass melt coated with octadecylamine. Piece.

Examples and comparative examples

Add the coated glass frit, organic binder, solvent, and dispersant according to the composition shown in Table 1 below (for example, weight %) and use a mixing mixer to disperse, and then mix the silver powder (spherical, average The particle size is 1㎛) and dispersed by a three-roll mill. Next, a conductive paste is produced by degassing under reduced pressure. Examples 1 to 6 used the glass frit obtained in accordance with Manufacturing Example 1 to Manufacturing Example 6, respectively, while Comparative Example 1 used a Pb-Te-Bi type glass frit that was not coated.

【Table 1】

Test example

(1) Coatability evaluation of glass frits

The surface-coated glass frit and the uncoated glass frit manufactured according to the above-mentioned Manufacturing Examples 1 to 6 were put into water, and the coating properties were compared and evaluated after stirring and standing. The comparative evaluation of the coatability was performed by visually observing the coatability after the solution with the glass frit was stirred and left for 24 hours. Figure 2 is a photograph taken of the state immediately after the glass frit is thrown into water and stirred and after it has been left for 24 hours in order to evaluate the coatability of the glass frit. As shown in Figure 2, the coating of glass frits coated with aliphatic amine compounds (manufacturing examples 1, 2, 5, and 6) and fatty acid-coated glass frits (manufacturing examples 3, 4) can be confirmed The cloth is in good condition. At this time, it can be found that the dispersibility of the glass frits coated with aliphatic amine compounds (manufacturing examples 1, 5, and 6) has been improved, so its volume has increased compared with uncoated glass frits. However, a lot of aggregation occurred in the fatty acid-coated glass frits (Production Examples 3 and 4).

(3) Thermogravimetric analysis (TGA)

Thermogravimetric analysis was performed on the surface-coated glass frit and the uncoated glass frit manufactured according to the above-mentioned manufacturing examples 1 to 6. Figures 3a and 3b are the results of thermogravimetric analysis of surface-coated glass frit and uncoated glass frit manufactured according to Manufacturing Example 1 to Manufacturing Example 6. As shown in Figure 3a, it can be found that the evaporation time of the coating material in the case of fatty acid coating is longer than that of the aliphatic amine compound coating. As shown in Figure 3b, it can be seen that as the content of aliphatic amine compounds (i.e., octadecylamine) increases, the weight loss also increases, which can confirm that it is uniformly coated.

(3) DSC analysis

DSC analysis was performed on the surface-coated glass frit and the uncoated glass frit manufactured according to the above-mentioned Manufacturing Example 1 to Manufacturing Example 6. Figures 4a and 4b are the results of DSC analysis of the surface-coated glass frit and uncoated glass frit manufactured according to Manufacturing Example 1 to Manufacturing Example 6. As shown in Figure 4a and Figure 4b, it can be found that the surface-coated glass frit and the uncoated glass frit produced according to the above-mentioned manufacturing examples 1 to 6 exhibit the same exothermic reaction. Example 6 shows a change in the crystallization of glass.

(4) Conversion efficiency and resistance measurement

Using the conductive paste manufactured in accordance with the above-mentioned Examples 1 to 6 and Comparative Example 1, pattern printing is performed on the front surface of the wafer by a 40㎛ mesh screen printing process, and then a belt drying oven is used at 200~350℃ The drying process is performed for 20 seconds to 30 seconds. Next, after printing aluminum paste on the back of the wafer, the same method is used for drying. The solar cell is manufactured by sintering the battery formed in the above process at 500 to 900° C. for 20 to 30 seconds in a belt sintering furnace.

The short-circuit current (Isc), open circuit voltage (Voc), conversion efficiency (Eff), fill factor (FF), series resistance ( Rs) and linear resistance (Rline) were measured, and the results are shown in Table 2 below.

【Table 2】

As shown in Table 2 above, it can be found that when the electrode of the solar cell is manufactured with a conductive paste containing a glass frit coated with an aliphatic amine compound (such as Examples 1, 2 and 5), The electrode of the solar cell is made with a conductive paste (Comparative Example 1 or Examples 3 and 4) containing glass frits without coating treatment or fatty acid coating treatment. Compared with the case where the open circuit voltage becomes larger and the series connection The resistance becomes smaller, and it can be confirmed that the power generation efficiency of the solar cell is improved due to its higher conversion efficiency.

In addition, comparing the cases of Examples 1, 5, and 6, it can be found that when the surface of the glass frit is coated with a lower content (Example 5), the conversion efficiency is greatly improved. From this, it can be confirmed that the dispersibility of the glass frit and the electrical characteristics of the solar cell electrode also change according to the content of the aliphatic group used in the coating process (in other words, the thickness of the coating).

(5) Adhesion evaluation 1

After using the conductive pastes manufactured according to the above-mentioned Examples 1, 4 and Comparative Example 1 to manufacture solar cells by the above-mentioned method, the ribbon wires are bonded by the tabbing process. Connected to the electrodes of each unit. The ribbon wire used is a product of 60Sn40Pb (Kosbon Company), which is bonded at 350°C with a soldering iron. Next, the adhesive force between the solar cell electrode and the ribbon wire was measured. The adhesive force measuring device used LS1 (Lloyd) products, and the adhesive force was measured at a direction of 180 degrees and a speed of 250 mm/min. Figure 5 is the result of measuring the adhesive force between the solar cell electrode and the ribbon wire manufactured using the conductive pastes manufactured according to Examples 1, 4 and Comparative Example 1. As shown in Figure 5, the adhesive force of the glass frits coated with aliphatic amine compounds (such as octadecylamine) (manufacturing example 1) is relatively uniform, while the glass frits coated with fatty acids (such as oleic acid) (Manufacturing Example 4) The adhesive force is uneven. Thereby, it can be concluded that the dispersibility of the glass frits coated with aliphatic amine compounds can be improved, while the dispersibility of the glass frits coated with fatty acids will decrease.

(6) Adhesion evaluation 2

After using the conductive pastes manufactured according to the above-mentioned Examples 1, 4 and Comparative Example 1 to manufacture the solar cell units by the above-mentioned method, the ribbon-shaped wires are formed by the above-mentioned tabbing process Bonded to the electrodes of each unit. Next, the bagged wire was removed and the image of the contact surface was measured. Figures 6a to 6c are the surface photos of the electrodes taken after the ribbon wire is removed. As shown in Fig. 1a to Fig. 6c, the electrode manufactured using the conductive paste of Example 1 has relatively uniform contact surface after removing the ribbon wire compared to the electrode manufactured using the conductive paste of Comparative Example 1 and Example 4. . Thereby, it can be concluded that the dispersibility of the glass frits coated with aliphatic amine compounds can be improved, while the dispersibility of the glass frits coated with fatty acids will decrease.

The features, structures, effects, etc. introduced in the various embodiments described above can be combined or modified with other embodiments by those skilled in the art to which the present invention belongs. Therefore, the content related to the combination or modification described above should also be interpreted as being included in the scope of the patent application of the present invention.

10‧‧‧P type silicon semiconductor substrate 20‧‧‧N type doped layer 30‧‧‧Anti-reflection film 40‧‧‧p+ layer 50‧‧‧Back aluminum electrode 60‧‧‧Back silver electrode 100‧‧‧Front electrode

Figure 1 is a schematic cross-sectional view of a general solar cell element.

Figure 2 is a photograph taken of the state immediately after the glass frit is thrown into water and stirred and after being left for 24 hours in order to evaluate the dispersibility of the glass frit.

Figures 3a and 3b are the results of thermogravimetric analysis of surface-coated glass frit and uncoated glass frit manufactured according to Manufacturing Example 1 to Manufacturing Example 6.

Figures 4a and 4b are the results of DSC analysis of the surface-coated glass frit and uncoated glass frit manufactured according to Manufacturing Example 1 to Manufacturing Example 6.

Figure 5 is the result of measuring the adhesive force between the solar cell electrode and the ribbon wire manufactured using the conductive paste manufactured according to Examples 1, 4 and Comparative Example 1.

Figures 6a to 6c are the surface photos of the electrodes taken after the ribbon wire is removed.

Claims (5)

A conductive paste for solar cell electrodes, comprising metal powder, glass frit and organic carrier, the surface of the glass frit is coated with an aliphatic amine compound; wherein the glass frit is the first glass frit, The conductive paste further includes a second glass frit, and the surface of the second glass frit is not coated or coated with fatty acid. The conductive paste for solar cell electrodes described in the first item of the scope of patent application, wherein the aliphatic amine compound contains an alkylamine substance having 6 to 24 carbon atoms. As described in item 2 of the scope of patent application, the conductive paste for solar cell electrodes, wherein the alkylamine substances include triethylamine, heptylamine, octadecylamine, and hexadecylamine ( Hexadecylamine, Decylamine, Octylamine, Didecylamine or Trioctylamine. The conductive paste for solar cell electrodes as described in item 1 of the scope of patent application, wherein the fatty acid contains lauric acid, oleic acid, stearic acid, palmitic acid or acetic acid. A solar cell in which a front electrode is provided on the upper part of a substrate and a back electrode is provided on the lower part of the substrate. The front electrode is coated by any one of items 1 to 4 in the scope of patent application. The conductive paste for solar cell electrodes described in the item is then manufactured by drying and sintering.

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