KR20120069159A - Aluminium paste composition and solar cell device using the same - Google Patents

Abstract

PURPOSE: An aluminum paste composition is provided to be environment-friendly because of not containing lead oxide(PbO) and bismuth oxide(Bi2O3) components, to prevent reaction with moisture due to thermal etching, and to restrain warpage phenomenon of silicon wafer because of high thermal expansion coefficient. CONSTITUTION: An aluminum paste composition comprises glass frit containing 50-80 mol% of V2O5 and 20-50 mol% of ZnO, and organic vehicle. The glass frit additionally comprises one or more kinds selected from a group consisting of SiO2, P2O5, alkaline metal oxide, and alkaline earth metal oxide. The aluminum powder comprises 60-95 weight% of powder with average particle size of 4-6 micron, and 5-40 weight% of powder with average particle size of 2-4 micron. The organic vehicle comprises 1-25 weight% of polymer resin, and 75-99 weight% of organic solvent.

Description

Aluminum paste composition and solar cell device using same {ALUMINIUM PASTE COMPOSITION AND SOLAR CELL DEVICE USING THE SAME}

The present invention relates to an aluminum paste composition which does not contain PbO and Bi ₂ O ₃ components, which is environmentally friendly and can also improve durability, and a solar cell device using the same.

Solar cells, which are rapidly spreading in recent years, are electronic devices that directly convert solar energy, which is clean energy, into electricity as a next generation energy source.

In the solar cell element, as shown in FIG. 1, an N + layer 20, an antireflection film 30, and a front electrode 40 are formed on the light-receiving surface side of the silicon wafer substrate 10, and opposite to the substrate 10. P + layer 50 and the back electrode 60 is formed on the surface side. When sunlight shines on a solar cell device having such a structure, electrons (-) and holes (+) are generated inside, and the generated electrons (-) are N + layers 20 and holes (+) are P + layers 50. Will move to each. Due to this phenomenon, a potential difference is generated between the P + layer 50 and the N + layer 20. At this time, the solar energy is converted into electrical energy on the principle that a current is generated when the load is connected.

Among these, the back electrode 60 is formed by applying an aluminum paste composition by screen printing, drying, and then firing the aluminum paste composition. When baking, aluminum is diffused into the silicon wafer substrate 10 so that the back electrode 60 and the substrate 10 are baked. An Al—Si alloy layer is formed therebetween and a P + layer 50 is formed by diffusion of aluminum atoms. The P + layer 50 acts as a back surface field (BSF) that prevents recombination of electrons and improves the collection efficiency of product carriers, and also serves as a reflector reflecting long wavelength light of sunlight.

The aluminum paste composition for forming the back electrode 60 includes aluminum powder, glass frit, and an organic vehicle. Among these, glass frit is a component for further strengthening the bond with the silicon wafer substrate 10 and is usually composed of PbO-B ₂ O ₃ -SiO _{2 type} , PbO-B ₂ O ₃ -Al ₂ O _{3 type} , and PbO- type. Those containing B ₂ O ₃ -ZnO-based oxides were mainly used.

Recently, due to environmental problems, Bi ₂ O ₃ -based oxides having similar properties to the PbO-based oxides without containing PbO components, such as Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ , Bi ₂ O ₃ -B ₂ O ₃ has been proposed to include -ZnO-based oxide. Korean Patent No. 0890866 discloses 0.5-35% by weight of SiO ₂ , 0-5% by weight of Al ₂ O ₃ , 1-15% by weight of B ₂ O ₃ , 0-15% by weight of ZnO and 55-90 weight of Bi ₂ O _3. A glass frit comprising% is disclosed. However, the glass frit containing the Bi ₂ O ₃ component heat-etches the oxide film on the surface of the aluminum powder of the aluminum layer to increase the moisture and reactivity, which has the disadvantage of lowering the durability of the solar cell device itself.

It is an object of the present invention to provide an aluminum paste composition which does not contain PbO and Bi ₂ O ₃ components and which is environmentally friendly and can also prevent reaction with moisture by thermal etching.

Another object of the present invention is to provide an electrode formed from the aluminum paste composition.

In addition, another object of the present invention is to provide a solar cell device provided with the electrode.

1.aluminum powder; Glass frit containing 50-80 mole percent V ₂ O ₅ and 20-50 mole percent ZnO; And an organic vehicle.

2. In the above 1, the glass frit is an aluminum paste composition further comprises one or more selected from the group consisting of Al ₂ O ₃ , B ₂ O ₃ , P ₂ O ₅ , SiO ₂ , alkali metal oxides and alkaline earth metal oxides .

3. In the above 2, Al ₂ O ₃ is 0.5-5 mol%, B ₂ O ₃ is 0.5-5 mol%, P ₂ O ₅ is 0-30 mol%, SiO with respect to 100 mol% of the glass frit composition ₂ is 0-15 mol%, an alkali metal oxide is 1-10 mol% and an alkaline earth metal oxide is contained in 0-30 mol%.

4. In the above 3, the glass frit is V ₂ O ₅ 50-70 mol%, ZnO 10-30 mol%, Al ₂ O ₃ 0.5-5 mol%, B ₂ O ₃ 0.5-5 mol% and alkali metal oxide Aluminum paste composition containing 1-10 mol%.

5. In the above 4, the alkali metal oxide is at least one aluminum paste composition selected from the group consisting of K ₂ O, Na ₂ O and Li ₂ O.

6. In the above 1, the glass frit has a softening point of 300-600 ℃ aluminum paste composition.

7. according to the above 1, 65-75% by weight of aluminum powder; 0.01-10% by weight glass frit; And 20-34.9% by weight of organic vehicle.

8. In the above 1, the aluminum powder is an aluminum paste composition of 60-95% by weight of the powder having an average particle size of 4-6㎛ and 5-40% by weight of the powder having an average particle size of 2-4㎛.

9. The aluminum paste composition of 1 above, wherein the organic vehicle is a mixture of 1-25% by weight of the polymer resin and 75-99% by weight of the organic solvent.

10. The electrode formed of the aluminum paste composition according to any one of the above 1 to 9.

11. Solar cell device provided with the electrode of the above 10.

The aluminum paste composition according to the present invention is environmentally friendly because it does not contain PbO components that are restricted in use due to environmental problems, and at the same time does not contain Bi ₂ O ₃ components having strong thermal etching properties, thereby preventing reaction with moisture. Through this, it is possible to enhance the durability of the solar cell element itself.

In addition, the aluminum paste composition of the present invention can suppress the warpage phenomenon of the silicon wafer substrate even with a relatively high coefficient of thermal expansion, can increase the maximum output current (Isc) of the solar cell device and improve the efficiency.

1 is a diagram schematically illustrating a cross-sectional view of a solar cell element.

The present invention relates to an aluminum paste composition containing no PbO and Bi ₂ O ₃ components and a solar cell device using the same.

Hereinafter, the present invention will be described in detail.

The aluminum paste composition of the present invention is aluminum powder; Glass frit; And V ₂ O ₅ -ZnO-based oxides, including organic vehicles, but not containing both PbO and Bi ₂ O ₃ components at the same time as the glass frit.

More specifically, the glass frit is characterized by containing 50-80 mole percent V ₂ O ₅ and 20-50 mole percent ZnO.

The aluminum powder is a conductive metal which is a main component of the paste composition for forming the back electrode, and it is preferable to use two kinds of mixed powders having different average particle sizes.

The silicon wafer substrate for forming the back electrode has a structure in which fine pyramids are formed on the surface by texturing both surfaces to increase the light receiving area of sunlight. Normally formed fine pyramids have a height of 2-15 μm and a width of 2-20 μm, and have an irregular maze shape. On the silicon wafer substrate having such a surface structure, the aluminum paste composition is printed by a method such as screen printing, gravure printing, or offset printing, dried, and then baked to form a back electrode. At this time, when the particle size of the aluminum powder is too large, the contact between the aluminum paste composition and the silicon wafer substrate is not good, and voids are formed between them after printing and drying. These voids pass through the aluminum paste layer and eject the surface during the firing process, resulting in aluminum bumps and bubbles. Therefore, it is desirable to minimize the size of the pores by mixing two kinds of aluminum powders having different average particle sizes.

The aluminum powder is preferably a mixture of 60-95 wt% of the powder having an average particle size of 4-6 μm and 5-40 wt% of the powder having an average particle size of 2-4 μm. The powder having an average particle size of 4-6 μm suppresses shrinkage of the silicon wafer substrate after firing to form a high density low shrink electrode, and the powder having an average particle size of 2-4 μm acts as a binder between the aluminum powders. The paste penetrates deeply and evenly into the textured surface of the substrate. In this case, the porosity between the substrate and the paste is reduced, the back electric field (BSF) is uniformly formed, the resistance of the back electrode is lowered, and the bending of the substrate is also suppressed. Therefore, it is possible to increase the maximum output current Isc of the solar cell device and increase efficiency, and to prevent yellowing occurring at the rear electrode after the firing process.

The aluminum powder is preferably included at 65-75% by weight relative to 100% by weight of the total content of the aluminum paste composition. If the content is less than 65% by weight, the thickness of the printed aluminum rear electrode after firing becomes thin so that the back field (BSF) may not be sufficiently formed and the efficiency may be lowered. When the content is more than 75% by weight, the thickness of the silicon wafer substrate is too thick. May cause warpage.

In the present invention, the glass frit is characterized by using a V ₂ O ₅ -ZnO-based oxide which does not contain a PbO component and a Bi ₂ O ₃ component at the same time.

Generally, glass frit containing PbO component has advantages of easy melting point control and low coefficient of thermal expansion, but its use is limited due to environmental problems. Glass frit containing Bi ₂ O ₃ component has similar characteristics to PbO glass frit. On the other hand, there is a disadvantage in that the reactivity of thermal etching the aluminum oxide film is too large to decrease the water resistance of the aluminum electrode and consequently the durability of the solar cell element.

In view of this point, the present invention is characterized by using a glass frit containing 50-80 mol% of V ₂ O ₅ and 20-50 mol% of ZnO.

More preferably, the glass frit is Al ₂ O ₃ ; B ₂ O ₃ ; P ₂ O ₅ ; SiO ₂ ; Alkali metal oxides such as K ₂ O, Na ₂ O, and Li ₂ O; Alkaline earth metal oxides such as MgO, CaO, SrO, and BaO may be contained alone or in combination of two or more thereof. At this time, Al ₂ O ₃ is 0.5-5 mol%, B ₂ O ₃ is 0.5-5 mol%, P ₂ O ₅ is 0-30 mol%, and SiO ₂ is 0-15 mol based on 100 mol% of the glass frit. %, Alkali metal oxide may be contained in 1-10 mol% and alkaline earth metal oxide in 0-30 mol%.

Most preferably, the glass frit is 50-70 mol% V ₂ O ₅ , 10-30 mol% ZnO, 0.5-5 mol% Al ₂ O _3, 0.5-5 mol% B ₂ O ₃ and alkali metal oxide 1-10 It is preferable to contain mol%.

It is preferable that a glass frit has a softening point of 300-600 degreeC. If the softening point is higher than 600 ° C., the glass frit must be melted to impart adhesion between the aluminum paste layer and the silicon wafer substrate, but the glass frit may not be sufficiently applied in the firing process, thereby decreasing the adhesion.

The glass frit is preferably contained in an amount of 0.01-10% by weight, more preferably 0.05-7% by weight, and most preferably 0.1-5% by weight, based on 100% by weight of the total content of the aluminum paste composition. If the content is less than 0.01% by weight, the adhesion between the aluminum back electrode and the silicon wafer substrate may be lowered after firing. If the content is more than 10% by weight, the resistance may be increased, thereby reducing the efficiency of the solar cell device.

The glass frit containing such a component does not contain a PbO component, which is environmentally friendly and does not contain a Bi ₂ O ₃ component, thereby preventing a decrease in water resistance due to thermal etching. On the other hand, glass frits that do not contain PbO components and Bi ₂ O ₃ components usually have a high melting point, so that a large amount of wood-based planting agent is used, which causes a relatively high coefficient of thermal expansion, which causes warpage of the silicon wafer substrate during solar cell device manufacturing. I could. However, the glass frit configured as in the present invention can be made to be negligible even if the thermal expansion coefficient is relatively high because each component is contained in the optimum molar ratio.

The organic vehicle is a component for imparting consistency and rheological properties suitable for printing to the aluminum paste composition, and may be a solution in which a polymer resin and various additives are dissolved in an organic solvent as necessary.

The organic vehicle may be a mixture of 75-99% by weight of the organic solvent and 1-25% by weight of the polymer resin, and may be a mixture of 1-10% by weight of the additive.

As the organic solvent, a known one may be used, and a solvent having a boiling point of 150 to 300 ° C. may be used to prevent drying of the paste composition and to control fluidity during the printing process. Specifically, tripropylene glycol methyl ether, tripropylene glycol n-butyl ether, dipropylene glycol n-propyl ether, dipropylene glycol n-butyl ether, propylene glycol phenyl ether, diethylene glycol ethyl ether, diethylene glycol n-butyl Ether, diethylene glycol hexyl ether, ethylene glycol hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol n-butyl ether, ethylene glycol phenyl ether, ethylene glycol, terpineol, butyl carbitol, butyl Carbitol acetate, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (texanol), and the like, and these may be used alone or in combination of two or more thereof.

The organic solvent is preferably included at 75-99% by weight based on 100% by weight of the total organic vehicle. In this content range, optimum fluidity can be imparted to the paste composition.

As the polymer resin, known ones can be used, for example, ethyl cellulose, nitrocellulose, phenol, acryl, rosin, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, polyvinyl butyral, urea, xylene, alkyd, unsaturated Polyester, polyimide, furan, urethane, isocyanate, cyanate, polyethylene, polypropylene, polystyrene, acrylonitrile-butadiene-styrene (ABS), polymethyl methacrylate, polyvinyl chloride, polyvinylidene chloride, polyvinyl Resins such as acetate, polyacetal, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyphenylene oxide, polysulfone, polyimide, polyether sulfone, polyarylate, polyether ether ketone and silicone Can be. These can be used individually or in mixture of 2 or more types.

The polymer resin may be included in an amount of 1-25 wt%, preferably 5-25 wt%, based on 100 wt% of the total organic vehicle content. When the content is less than 1% by weight, the printability and dispersion stability of the paste composition may be lowered, and when the content is more than 25% by weight, the paste composition may not be printed.

The organic vehicle may further comprise a dispersant as an additive together with the above components.

As the dispersant, a known surfactant can be used, for example, polyoxyethylene alkyl ether having 6 to 30 carbon atoms in the alkyl group, polyoxyethylene alkyl aryl ether having 6 to 30 carbon atoms in the alkyl group, and 6 to 30 carbon atoms in the alkyl group. Ethers such as polyoxyethylene-polyoxypropylene alkyl ether; Ester ethers such as glycerin ester addition polyoxyethylene ether, sorbitan ester addition polyoxyethylene ether, and sorbitol ester addition polyoxyethylene ether; Esters such as polyethylene glycol fatty acid ester, glycerin ester, sorbitan ester, propylene glycol ester, sugar ester and alkyl polyglucoside; Nitrogen-containing systems such as fatty acid alkanolamide, polyoxyethylene fatty acid amide, polyoxyethylene alkylamine having 6 to 30 carbon atoms of an alkyl group, and amine oxide; And high molecular compounds such as polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, polyacrylic acid-maleic acid copolymer, and poly12-hydroxystearic acid. Commercially available products include Hypermer KD (Uniqema), AKM 0531 (Japan Oil Holding Co., Ltd.), KP (Shin-Etsu Chemical Co., Ltd.), POLYFLOW (Kyoeisha Chemical Co., Ltd.), EFTOP (Tochem Products), Asahi guard (Asahi Glass, Inc.), Suflon (Asahi Glass, Inc.), SOLSPERSE (Genekka), EFKA (EFKA Chemicals, Inc.) ), PB 821 (Ajinomoto Co., Ltd.), BYK-184, BYK-185, BYK-2160, Anti-Terra U (manufactured by BYK), and the like can also be used. These can be used individually or in mixture of 2 or more types.

The dispersant may be included in an amount of 1-10% by weight, preferably 1-5% by weight, based on 100% by weight of the total amount of the organic vehicle.

The organic vehicle may further include additives such as thixotropic agents, wetting agents, antioxidants, corrosion inhibitors, antifoaming agents, thickeners, dispersants, tackifiers, coupling agents, antistatic agents, polymerization inhibitors, and antisettling agents.

The organic vehicle is preferably included in 20-34.9% by weight relative to 100% by weight of the total content of the aluminum paste composition. If the content is less than 20% by weight, the viscosity of the aluminum paste composition may be too high, which may lower fluidity and reduce printability. If the content is more than 34.9% by weight, the aluminum powder content may be relatively small to ensure sufficient thickness of the paste layer. it's difficult.

The aluminum paste composition containing the above components does not contain PbO, which is restricted in use due to environmental problems, and is not only environmentally friendly but also does not contain Bi ₂ O ₃ , which is highly thermally etched. Can be.

The present invention provides an electrode formed from the aluminum paste composition.

The electrode is formed through a process of printing, drying, and firing an aluminum paste composition on a substrate such as a silicon wafer substrate on which an Ag front electrode is formed. The printing method is not particularly limited, and for example, screen printing, gravure printing, offset printing and the like can be used. Drying is carried out at 60-300 ° C. for several seconds-minutes, and firing can be carried out at 600-950 ° C. for several seconds.

The electrode formed as described above may be applied to the rear electrode of the solar cell device, thereby improving durability of the solar cell device, increasing the maximum output current Isc of the solar cell device, and increasing efficiency.

The present invention provides a solar cell device provided with an electrode formed from the aluminum paste composition.

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but these examples are merely illustrative of the present invention and are not intended to limit the scope of the appended claims. It is apparent to those skilled in the art that various changes and modifications can be made to the present invention, and such modifications and changes belong to the appended claims.

Example

Preparation Example 1-8. Preparation of Glass Frit I-B

Glass frits were prepared with the ingredients and contents as shown in Table 1 below.

division Kinds Component (mol%) Tg
(℃) CTE
(10 ^-7 / ℃) V ₂ O ₅ ZnO Bi ₂ O ₃ Al ₂ O ₃ B ₂ O ₃ PbO P ₂ O ₅ SiO ₂ R ₂ O RO Preparation Example 1 I 63.35 23.99 - 1.75 1.72 - - - 9.19 - 346 103 Preparation Example 2 Ⅱ 65 35 - - - - - - - - 379 98 Production Example 3 Ⅲ 32.34 13.2 - - - - 29.26 - - 25.2 420 96 Production Example 4 Ⅳ - - 15 15 24 - - 46 - - 520 68 Production Example 5 Ⅴ - 9 17 9 39 - - 26 - - 505 70 Production Example 6 VI - 53 30 - 4 13 - - - - 454 48 Preparation Example 7 Ⅶ 45.35 41.99 - 1.75 1.72 - - - 9.19 - 367 102 Preparation Example 8 Ⅷ 81.85 5.49 - 1.75 1.72 - - - 9.19 - 325 115 R ₂ O: alkali metal oxide (K ₂ O, Na ₂ O, Li ₂ O)
RO: alkaline earth metal oxides (SrO, BaO, CaO)
Tg: Softening Point
CTE: coefficient of thermal expansion

Example 1

74% by weight of a mixed powder in which an aluminum powder having an average particle size of 4-6 μm and an aluminum powder having an average particle size of 2-4 μm were mixed at a weight ratio of 90:10; 0.5 wt% of Glass Frit I of Preparation Example 1; After adding 25.5% by weight of an organic vehicle in which ethyl cellulose resin was dissolved in tripropylene glycol methyl ether, an aluminum paste composition was prepared by stirring at 1,000 rpm for 3 minutes using a mixer that simultaneously rotates and rotates.

Example 2

The same procedure as in Example 1, except that Glass Frit II of Preparation Example 2 was used.

Comparative Example 1

The same procedure as in Example 1, except that Glass Frit III of Preparation Example 3 was used.

Comparative Example 2

The same procedure as in Example 1, except that the glass frit VI of Preparation Example 4 was used.

Comparative Example 3

The same procedure as in Example 1, except that glass frit V of Preparation Example 5 was used.

Comparative Example 4

The same procedure as in Example 1, except that glass frit VI of Preparation Example 6 was used.

Comparative example  5

It carried out similarly to Example 1, but used the glass frit of Preparation Example 7.

Comparative Example 6

It carried out similarly to Example 1, but used the glass frit of Preparation Example 8.

Test Example

The physical properties of the aluminum paste compositions prepared in Examples and Comparative Examples were measured by the following methods, and the results are shown in Table 2 below.

-Screen of 250 mesh aluminum paste composition prepared on the back side of the single crystal silicon wafer substrate having a pyramid structure having a size of 156 mm x 156 mm, a thickness of 200 m and a height of about 4-6 m by a texturing process. It was applied using a printing plate. At this time, the coating amount was set to 1.4 ± 0.1g before drying. The applied paste was dried at 200 ° C. and then fired for about 10 seconds in an infrared continuous kiln at a temperature of 720-900 ° C. The firing process is carried out by simultaneous firing front and back while passing the silicon wafer substrate into a belt furnace comprising a burn-out section of about 600 ° C. and a firing section of 800-950 ° C. After removing the organic material in the paste, the aluminum was melted to form an electrode, thereby manufacturing a solar cell device.

(1) water resistance

The prepared solar cell device was placed in a thermostatic chamber filled with distilled water at 80 ° C. and left for 10 minutes. After visual observation of the generation of hydrogen gas (bubble) due to the reaction of the aluminum electrode formed in the thermostat and the moisture was evaluated based on the following criteria.

<Evaluation Criteria>

(Circle): No bubble generation (good).

X: Bubble generation (defect).

(2) deflection (mm)

The manufactured solar cell device was placed on a flat bottom and four corners were aligned with the bottom, and then the degree of lifting of the center part was measured.

(3) Efficiency (%)

The efficiency of the manufactured solar cell device was evaluated using an evaluation device (SCM-1000, FitTech).

division Water resistance Deflection (mm) efficiency(%) Example 1 ○ 1.2 ± 0.2 17.7 ± 0.2 Example 2 ○ 1.4 ± 0.2 17.5 ± 0.2 Comparative Example 1 ○ 1.9 ± 0.3 17.1 ± 0.3 Comparative Example 2 × 1.7 ± 0.4 17.5 ± 0.3 Comparative Example 3 × 1.4 ± 0.3 17.5 ± 0.3 Comparative Example 4 × 1.7 ± 0.5 17.5 ± 0.3 Comparative Example 5 ○ 2.3 ± 0.2 17.6 ± 0.2 Comparative Example 6 ○ 2.1 ± 0.2 17.5 ± 0.2

As shown in Table 2, the solar cell device using the aluminum paste composition of Examples 1 and 2 including a glass frit containing P ₂ O ₅ and ZnO as a main component without PbO and Bi ₂ O ₃ according to the present invention As it is environmentally friendly and prevents reaction with moisture, it has excellent water resistance, which can improve the durability of the solar cell device, and it can be confirmed that the curvature can be suppressed even with a relatively high coefficient of thermal expansion and high efficiency. In particular, when using an aluminum paste composition containing Al ₂ O ₃ , B ₂ O ₃ and alkali metal oxides with V ₂ O ₅ and ZnO in an optimum content, it was most effective in securing water resistance while minimizing the amount of warpage.

On the other hand, the solar cell device using the aluminum paste composition of Comparative Examples 2 to 4 containing a glass frit containing Bi ₂ O ₃ was not good water resistance due to the reactivity with water, especially Comparative Example 4 containing a PbO component Is not environmentally friendly either. In addition, Comparative Examples 1, 5, and 6, in which the contents of V ₂ O ₅ and ZnO are not optimized even though they do not contain Bi ₂ O ₃ , can improve the water resistance, but the warpage of the wafer substrate is increased or the efficiency is decreased.

10: silicon wafer substrate 20: N + layer
30: antireflection film 40: front electrode
50: P + layer 60: rear electrode

Claims (11)

Aluminum powder;
Glass frit containing 50-80 mole percent V ₂ O ₅ and 20-50 mole percent ZnO; And
An aluminum paste composition comprising an organic vehicle.
The aluminum paste composition of claim 1, wherein the glass frit further contains at least one selected from the group consisting of Al ₂ O ₃ , B ₂ O ₃ , P ₂ O ₅ , SiO ₂ , alkali metal oxides and alkaline earth metal oxides.
The method according to claim 2, Al ₂ O ₃ is 0.5-5 mol%, B ₂ O ₃ is 0.5-5 mol%, P ₂ O ₅ is 0-30 mol%, SiO ₂ with respect to 100 mol% of the glass frit composition An aluminum paste composition containing 0-15 mol%, alkali metal oxide 1-10 mol% and alkaline earth metal oxide 0-30 mol%.
The glass frit of claim 3, wherein the glass frit is 50-70 mol% of V ₂ O ₅ , 10-30 mol% of ZnO, 0.5-5 mol% of Al ₂ O _3, 0.5-5 mol% of B ₂ O _3, and alkali metal oxide 1-. Aluminum paste composition containing 10 mol%.
The aluminum paste composition of claim 4, wherein the alkali metal oxide is at least one member selected from the group consisting of K ₂ O, Na ₂ O, and Li ₂ O.
The aluminum paste composition of claim 1, wherein the glass frit has a softening point of 300-600 ° C.
The method of claim 1, wherein the aluminum powder 65-75% by weight; 0.01-10% by weight glass frit; And 20-34.9% by weight of organic vehicle.
The aluminum paste composition of claim 1, wherein the aluminum powder is mixed with 60-95 wt% of the powder having an average particle size of 4-6 μm and 5-40 wt% of the powder having an average particle size of 2-4 μm.
The aluminum paste composition of claim 1, wherein the organic vehicle is a mixture of 1-25% by weight of the polymer resin and 75-99% by weight of the organic solvent.
An electrode formed of the aluminum paste composition according to claim 1.
Solar cell device provided with the electrode of claim 10.

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