KR102052201B1 - Composition for forming solar cell electrode and electrode prepared using the same - Google Patents

Abstract

A conductive powder, a glass frit and an organic vehicle, wherein the glass frit comprises a mixture of a first glass frit having a melting temperature of 400 ° C. to 600 ° C. and a second glass frit having a melting temperature of 650 ° C. to 800 ° C. , A composition for forming a solar cell electrode, and an electrode formed therefrom are provided.

Description

A composition for forming a solar cell electrode and an electrode manufactured therefrom {COMPOSITION FOR FORMING SOLAR CELL ELECTRODE AND ELECTRODE PREPARED USING THE SAME}

The present invention relates to a composition for forming a solar cell electrode and an electrode prepared therefrom. More specifically, the present invention includes a mixture of the first glass frit and the second glass frit having the melting temperature of the present invention, which is excellent in contact resistance and wire resistance, and improves pull strength to improve reliability. It relates to a composition for forming a solar cell electrode and an electrode prepared therefrom.

Solar cells generate electrical energy using the photoelectric effect of pn junctions that convert photons of sunlight into electricity. In the solar cell, front and rear electrodes are formed on upper and lower surfaces of a semiconductor wafer or substrate on which a pn junction is formed. The photovoltaic effect of the pn junction is induced by solar light incident on the semiconductor wafer, and electrons generated therefrom provide a current flowing through the electrode to the outside. The electrode of such a solar cell may be formed on the wafer surface by applying, patterning, and firing an electrode paste composition.

In recent years, as the thickness of the emitter is continuously thinned to increase the efficiency of the solar cell, it may cause a shunting phenomenon that may degrade the performance of the solar cell. In addition, in order to increase the efficiency of the solar cell, the area of the solar cell is gradually increased, and the sheet resistance of the wafer is gradually increasing, which can reduce the efficiency of the solar cell by increasing the contact resistance of the solar cell.

Therefore, the paste composition for electrodes which can improve the contact resistance and the line resistance and improve the solar cell efficiency by minimizing the damage to the bonding of the emitter layer under various sheet resistance and improving the conductivity at the interface between the wafer and the electrode. Need to develop

Background art of the present invention is disclosed in Japanese Patent Laid-Open No. 2015-144162 or the like.

The problem to be solved by the present invention is to provide a composition for forming a solar cell electrode that can improve the reliability by increasing the contact resistance and wire resistance excellent electrical properties and tensile strength.

Another problem to be solved by the present invention is to provide a solar cell electrode having high reliability due to excellent electrical properties and low tensile resistance due to low contact resistance and wire resistance.

The composition for forming a solar cell electrode of the present invention includes a conductive powder, a glass frit and an organic vehicle, wherein the glass frit has a melting temperature (Tm) of 400 ° C. to 600 ° C. and a first glass frit having a melting temperature of 650. It may include a mixture of the second glass frit is ℃ to 800 ℃.

In one embodiment, the first glass frit may be a tellurium-bismuth-based glass frit including tellurium (Te) and bismuth (Bi) elements.

In one embodiment, the first glass frit is zinc (Zn), lead (Pb), phosphorus (P), germanium (Ge), gallium (Ga), cerium (Ce), iron (Fe), lithium (Li) , Silicon (Si), tungsten (W), magnesium (Mg), cesium (Cs), strontium (Sr), molybdenum (Mo), titanium (Ti), tin (Sn), indium (In), vanadium (V) , Barium (Ba), nickel (Ni), copper (Cu), sodium (Na), potassium (K), arsenic (As), cobalt (Co), zirconium (Zr), manganese (Mn), aluminum (Al) And at least one element selected from the group consisting of oxides thereof.

In one embodiment, the second glass frit may be a tellurium-bismuth-based glass frit including tellurium (Te) and bismuth (Bi) elements.

In one embodiment, the first glass frit and the second glass frit may be included in a weight ratio of 6: 1 to 1: 1.

In one embodiment, the first glass frit is contained in 0.5 wt% to 10 wt% of the total weight of the composition for forming a solar cell electrode, the second glass frit is 0.1 weight in the total weight of the composition for forming a solar cell electrode % To 5% by weight may be included.

In one embodiment, the composition may include 60% to 95% by weight of the conductive powder, 1% to 20% by weight of the glass frit, and the balance of the organic vehicle.

In one embodiment, the composition may further comprise one or more additives of a dispersant, thixotropic agent, plasticizer, viscosity stabilizer, antifoaming agent, pigment, UV stabilizer, antioxidant, coupling agent.

The electrode of the present invention can be prepared with the composition for forming a solar cell electrode of the present invention.

The present invention provides a composition for forming a solar cell electrode which can improve reliability by increasing contact strength and wire resistance, thereby improving electrical properties and increasing tensile strength.

The present invention provides a solar cell electrode having high reliability due to excellent electrical characteristics and high tensile strength due to low contact resistance and wire resistance.

1 is a schematic diagram schematically showing the structure of a solar cell according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, it will be described embodiments of the present application in more detail. However, the technology disclosed in the present application is not limited to the embodiments described herein and may be embodied in other forms.

In this specification, the "melting temperature" of a glass frit can be measured by the thermogravimetry and differential thermal (TG-DTA) method.

In the present specification, the content (mol%) of each metal element included in the glass frit may be measured by an inductively coupled plasma-optical emission spectrometer (ICP-OES). Since the inductively coupled plasma-atomic emission spectroscopy (ICP-OES) uses a very small amount of sample, it can shorten the sample preparation time, reduce the error due to sample pretreatment, and have an excellent analysis sensitivity.

Specifically, the inductively coupled plasma-atomic emission spectroscopy (ICP-OES) is a step of pre-treating a sample, preparing a standard solution, and measuring and converting the concentration of the element to be measured to determine the content of each element present in the glass frit. Can be measured precisely.

The pretreatment of the sample may carbonize the sample by dissolving and heating the sample in an appropriate amount using an acid solution capable of dissolving the glass frit. As the acid solution, for example, a sulfuric acid (H ₂ SO ₄ ) solution may be used.

The carbonized sample may be appropriately diluted to a range of analytical concentration of the element to be analyzed with a solvent such as distilled water and hydrogen peroxide (H ₂ O ₂ ). The analytical concentration range may be used in a diluted state of about 10,000 times in consideration of the element detection capability of the applied ICP-OES device.

The pretreated sample may be calibrated with a standard solution, for example, a standard solution of an element to be analyzed for element measurement when measured with an ICP-OES instrument. For example, by introducing the standard solution into the ICP-OES measuring device to create a calibration curve by an external standard method (concentration) of the metal element to be analyzed of the sample pre-treated with the ICP-OES measuring device ( ppm) can be measured and converted to calculate the molar ratio of each element in the glass frit.

Composition for forming solar cell electrode

The composition for forming a solar cell electrode of the present invention includes a conductive powder, a glass frit, and an organic vehicle, wherein the glass frit has a melting temperature and melting temperature of the first glass frit having a melting temperature (Tm) of 400 ° C to 600 ° C. It may comprise a mixture of the second glass frit is 650 ℃ to 800 ℃. The inventors of the present invention, the composition for forming a solar cell electrode comprising a mixture of the first glass frit and the second glass frit has a low contact resistance and a low line resistance, excellent electrical properties and high tensile strength can be improved reliability. It was found and completed the present invention.

Hereinafter, each component in the composition of the present invention will be described in detail.

Conductive powder

The conductive powder may include silver (Ag) powder. The silver powder may be a powder having a particle size of nano size or micro size, for example, may be a silver powder of several tens to hundreds of nanometers in size, silver powder of several to several tens of micrometers. In addition, the silver powder may be used by mixing silver powder having two or more different sizes.

The conductive powder is not particularly limited in particle shape, and particles of various shapes, for example, spherical, plate or amorphous particles, may be used without limitation.

The average particle diameter (D50) of the conductive powder is 0.1 μm to 10 μm, preferably 0.5 μm to 5 μm. Within this range, the contact resistance and the wire resistance can be lowered. The average particle diameter (D50) was measured using a 1064LD model manufactured by CILAS after dispersing the conductive powder in isopropyl alcohol (IPA) at 25 ° C. for 3 minutes with ultrasonic waves.

The conductive powder may be included in 60% by weight to 95% by weight of the total weight of the composition for forming a solar cell electrode. When the content of the conductive powder satisfies the above range, the change efficiency of the solar cell is excellent and the paste can be made smoothly. Preferably, the conductive powder may be included in 70% by weight to 90% by weight of the total weight of the composition for forming a solar cell electrode.

Glass frit

The glass frit is for etching the anti-reflection film during the firing process of the composition for forming a solar cell electrode and melting the conductive powder to generate crystal particles of the conductive powder in the emitter region. In addition, the glass frit improves the adhesion between the conductive powder and the wafer and softens during sintering to induce an effect of lowering the firing temperature.

The composition for forming a solar cell electrode of the present invention includes a mixture of the first glass frit and the second glass frit having different melting temperatures and having a specific melting temperature range. In general, in order to lower the contact resistance and wire resistance and improve the tensile strength, the content of the glass frit may be increased, and thus the open voltage may be decreased. However, the present invention includes a mixture of the first glass frit and the second glass frit having different melting temperatures and having a melting temperature range of the present invention, thereby reducing contact resistance and wire resistance while minimizing a drop in open voltage, and improving tensile strength. Could.

Hereinafter, the first glass frit and the second glass frit will be described in detail.

(A) 1st glass frit

The first glass frit may have a melting temperature of 400 ° C to 600 ° C. Within this range, the contact resistance and the line resistance can be lowered. Preferably, the melting temperature of the first glass frit may be 450 ° C to 500 ° C.

The first glass frit may be a tellurium-bismuth-based glass frit including tellurium (Te) and bismuth (Bi) elements. The first glass frit may include the tellurium and bismuth elements to easily secure the melting temperature, and stably etch the anti-reflection film to improve the contact resistance.

The first glass frit may further contain metal and / or metal oxide, in addition to tellurium and bismuth. For example, the first glass frit includes zinc (Zn), lead (Pb), phosphorus (P), germanium (Ge), gallium (Ga), cerium (Ce), iron (Fe), lithium (Li), Silicon (Si), tungsten (W), magnesium (Mg), cesium (Cs), strontium (Sr), molybdenum (Mo), titanium (Ti), tin (Sn), indium (In), vanadium (V), Barium (Ba), nickel (Ni), copper (Cu), sodium (Na), potassium (K), arsenic (As), cobalt (Co), zirconium (Zr), manganese (Mn), aluminum (Al) and It may further comprise one or more elements selected from the group consisting of oxides thereof.

In one embodiment, the first glass frit may be a Te-Bi-O-based glass frit containing tellurium, bismuth element. Preferably, the Te-Bi-O-based glass frit may include 45 mol% to 75 mol% of tellurium and 5 mol% to 20 mol% of bismuth. It is possible to implement excellent contact resistance and line resistance in the above range.

In another embodiment, the first glass frit may be a Te-Bi-Zn-O based glass frit comprising tellurium, bismuth, and zinc elements. Preferably, the Te-Bi-Zn-O-based glass frit may include 45 mol% to 75 mol% of tellurium, 5 mol% to 20 mol% of bismuth, and 1 mol% to 20 mol% of zinc. In the above range, it is possible to implement excellent contact resistance and line resistance.

The first glass frit can be made from tellurium oxide, bismuth oxide and optionally from the metal and / or metal oxide using conventional methods. For example, the tellurium oxide, bismuth oxide and optionally the metal and / or metal oxide may be mixed using a ball mill or planetary mill, or the like, followed by mixing the mixed composition into 800 The first glass frit may be obtained by melting at a temperature of 1 ° C. to 1300 ° C., quenching at 25 ° C., and then grinding the resultant by a disk mill, planetary mill, or the like.

The first glass frit may be included in 0.5 wt% to 10 wt% of the total weight of the composition for forming a solar cell electrode. When the content of the first glass frit satisfies the above range, the first glass frit has excellent contact resistance and line resistance, and the tensile strength can be increased. Preferably, the first glass frit may be included in 1% by weight to 6% by weight of the total weight of the composition for forming a solar cell electrode.

(B) 2nd glass frit

The second glass frit may have a melting temperature of 650 ° C to 800 ° C. Within this range, it is possible to prevent the minimization of the open voltage and to have excellent tensile strength. Preferably, the melting temperature of the second glass frit may be 700 ℃ to 750 ℃.

The second glass frit may be a tellurium-bismuth-based glass frit including tellurium and bismuth elements. When both the first glass frit and the second glass frit contain elemental tellurium, tensile strength may be further improved.

The second glass frit may further contain metal and / or metal oxide in addition to tellurium and bismuth. For example, the second glass frit includes zinc (Zn), lead (Pb), phosphorus (P), germanium (Ge), gallium (Ga), cerium (Ce), iron (Fe), lithium (Li), Silicon (Si), tungsten (W), magnesium (Mg), cesium (Cs), strontium (Sr), molybdenum (Mo), titanium (Ti), tin (Sn), indium (In), vanadium (V), Barium (Ba), nickel (Ni), copper (Cu), sodium (Na), potassium (K), arsenic (As), cobalt (Co), zirconium (Zr), manganese (Mn), aluminum (Al) and It may further comprise one or more elements selected from the group consisting of oxides thereof.

In one embodiment, the second glass frit may be a Te-Bi-O based glass frit comprising tellurium and bismuth elements. Preferably, the Te-Bi-O-based glass frit may include 5 mol% to 20 mol% of tellurium and 10 mol% to 30 mol% of bismuth. In the above range may be an effect of improving the tensile strength.

In another embodiment, the second glass frit may be a Te-Bi-W-O based glass frit comprising tellurium, bismuth and tungsten elements. Preferably, the Te-Bi-W-O-based glass frit may include 5 mol% to 20 mol% of tellurium, 10 mol% to 30 mol% of bismuth, and 5 mol% to 30 mol% of tungsten. In the above range may be an effect of improving the tensile strength.

The second glass frit can be made from tellurium oxide, bismuth oxide and optionally from the metal and / or metal oxide using conventional methods. The manufacturing method is substantially the same as described in the first glass frit.

The second glass frit may be included in an amount of 0.1 wt% to 5 wt% of the total weight of the composition for forming a solar cell electrode. When the content of the second glass frit satisfies the above range, the contact resistance and the wire resistance can be lowered and the tensile strength can be increased. Preferably, the second glass frit may be included in 0.5 wt% to 3 wt% of the total weight of the composition for forming a solar cell electrode.

The shape and size of each of the first glass frit and / or the second glass frit is not particularly limited. For example, the first glass frit or the second glass frit may have an average particle diameter D50 of 0.1 μm to 10 μm, respectively. The shape of the first glass frit or the second glass frit may be spherical or irregular. The average particle diameter (D50) is measured using a 1064LD model manufactured by CILAS after dispersing the glass frit powder in isopropyl alcohol (IPA) at 25 ℃ by ultrasonic for 3 minutes.

Meanwhile, in the present invention, the first glass frit and the second glass frit may be included in a weight ratio (first glass frit: second glass frit) of 6: 1 to 1: 1. In the above range it may be effective to lower the contact resistance and wire resistance and improve the tensile strength. Preferably, it may be included in a weight ratio of 4: 1 to 1: 1.

On the other hand, the content of the total glass frit including the first glass frit and the second glass frit may be 1 to 20% by weight, preferably 2 to 15% by weight relative to the total weight of the composition for forming a solar cell electrode. . When it is contained in the above range, it is possible to secure the pn junction stability under various sheet resistance, to minimize the line resistance value, and finally to improve the efficiency of the solar cell.

abandonment Vehicle

The organic vehicle imparts suitable viscosity and rheological properties to the composition through mechanical mixing with the inorganic component of the composition for forming a solar cell electrode.

As the organic vehicle, an organic vehicle that is typically used in a composition for forming a solar cell electrode may be used, and may include a binder resin, a solvent, and the like.

As the binder resin, an acrylate-based or cellulose-based resin may be used, and ethyl cellulose is generally used. However, ethyl hydroxyethyl cellulose, nitro cellulose, a mixture of ethyl cellulose and phenol resin, alkyd resin, phenol resin, acrylic ester resin, xylene resin, polybutene resin, polyester resin, urea resin, melamine Resins, vinyl acetate-based resins, wood rosins, or polymethacrylates of alcohols;

Examples of the solvent include hexane, toluene, ethyl cellosolve, cyclohexanone, butyl cellosolve, butyl carbitol (diethylene glycol monobutyl ether), dibutyl carbitol (diethylene glycol dibutyl ether) Butyl carbitol acetate (diethylene glycol monobutyl ether acetate), propylene glycol monomethyl ether, hexylene glycol, terpineol, methyl ethyl ketone, benzyl alcohol, gamma butyrolactone or ethyl lactate alone or the like It can mix and use 2 or more types.

The organic vehicle may be included as the remainder in the composition for forming a solar cell electrode, and may preferably be included in an amount of 1% to 30% by weight based on the total weight. It is possible to secure sufficient adhesive strength and excellent printability in the above range.

additive

The composition for forming a solar cell electrode of the present invention may further include a conventional additive as needed to improve the flow characteristics, process characteristics and stability in addition to the components described above. The additives may be used alone or in combination of two or more of a dispersant, thixotropic agent, plasticizer, viscosity stabilizer, antifoaming agent, pigment, ultraviolet stabilizer, antioxidant, coupling agent and the like. These may be included in 0.1 wt% to 5 wt% of the total weight of the composition for forming a solar cell electrode, but may be changed in content as necessary.

Solar cell electrode and solar cell comprising same

Another aspect of the invention relates to an electrode formed from the composition for forming a solar cell electrode and a solar cell comprising the same. 1 illustrates a structure of a solar cell according to an embodiment of the present invention.

Referring to FIG. 1, a composition for forming an electrode is printed and baked on a wafer 100 or a substrate including a p layer (or n layer) 101 and an n layer (or p layer) 102 as an emitter. Thus, the rear electrode 210 and the front electrode 230 may be formed. For example, the electrode forming composition may be printed on the back side of the wafer and then dried at a temperature of about 200 ° C. to 400 ° C. for about 10 to 60 seconds to perform a preliminary preparation step for the back electrode. In addition, the composition for forming an electrode on the front surface of the wafer may be printed and dried to perform a preliminary preparation step for the front electrode. Thereafter, a firing process may be performed at 400 ° C. to 950 ° C., preferably 700 ° C. to 950 ° C., for about 30 seconds to 210 seconds to form a front electrode and a rear electrode.

Hereinafter, the configuration and operation of the present invention through the embodiments of the present invention will be described in more detail. However, the following examples are provided to help the understanding of the present invention, and the scope of the present invention is not limited to the following examples.

Detailed configurations of the glass frit used in the following Examples and Comparative Examples are shown in Table 1 and Table 2. Table 1 below shows the first glass frit, and Table 2 below shows the second glass frit. The content of each metal element included in each glass frit in the first glass frit and the second glass frit was measured by ICP-OES described above. The melting temperature of each glass frit in the first glass frit and the second glass frit was measured by the TG-DTA method described above.

Te
(mole%) Bi
(mole%) Zn
(mole%) Li
(mole%) W
(mole%) Melting temperature
(℃) A1 75.0 10.5 7.0 4.5 3.0 400 A2 60.5 12.5 12.5 4.0 10.5 600 A3 70.0 10.0 5.0 12.0 3.0 380 A4 60.5 12.5 10.0 3.5 13.5 620

Te
(mole%) Bi
(mole%) Zn
(mole%) Li
(mole%) W
(mole%) Si
(mole%) Melting temperature
(℃) B1 15.0 15.0 14.5 13.5 7.0 35.0 650 B2 10.0 15.0 15.0 9.0 15.0 36.0 800 B3 20.0 10.0 14.5 15.5 5.0 35.0 630 B4 10.0 17.0 13.5 7.0 30.0 22.5 820

Example  One

1.0 wt% of ethyl cellulose (Dow chemical company, STD4) as an organic binder was sufficiently dissolved in 6.5 wt% of butyl carbitol as a solvent at 60 ° C., and then spherical silver powder having a mean particle size of 1.0 μm (Dowa Hightech CO. LTD, AG-4-8) 89.0% by weight, 3.0% by weight of glass frit, 0.2% by weight of dispersant BYK102 (BYK-chemie) and 0.3% by weight of thixotropic agent Thixatrol ST (Elementis co.) As an additive. Mixing and dispersing with a roll kneader to prepare a composition for forming a solar cell electrode. At this time, the glass frit contained the first glass frit and the second glass frit in Table 1 and Table 2 in the amounts shown in Table 3 below.

Example  2 to Example  4

In Example 1, a composition for forming a solar cell electrode was prepared in the same manner except for changing the type and content of the first glass frit and the second glass frit as shown in Table 3 below.

Comparative example  One

In Example 1, a composition for forming a solar cell electrode was prepared in the same manner except that the second glass frit was not included.

Comparative example  2

In Example 1, a composition for forming a solar cell electrode was prepared in the same manner except that the first glass frit was not included.

Comparative example  3

Except for using A3 instead of the first glass frit A1 in Example 1 to prepare a composition for forming a solar cell electrode.

Comparative example  4

Except for using A4 instead of the first glass frit A1 in Example 1 to prepare a composition for forming a solar cell electrode.

Comparative example  5

Except for using B3 instead of the second glass frit B1 in Example 1 to prepare a composition for forming a solar cell electrode.

Comparative example  6

Except for using B4 instead of the second glass frit B1 in Example 1 to prepare a composition for forming a solar cell electrode.

After manufacturing a solar cell using the composition for forming a solar cell electrode prepared in Examples and Comparative Examples as described below, the contact resistance, wire resistance and tensile strength were measured for each, the results are shown in Table 3 below. Indicated.

Solar cell manufacturing

After texturing the front surface of the wafer (a p-type wafer doped with boron) of the solar cell electrode forming composition prepared in Examples and Comparative Examples, an n + layer was formed on POCL3 and formed thereon. Multi-crystalline wafers formed of silicon nitride (SiNx: H) as an antireflection film) were printed by screen printing in a predetermined pattern and dried at 300 to 400 ° C. for 1 minute using an infrared drying furnace. After printing the aluminum paste on the back of the wafer and dried in the same manner. The cell formed by the above process was fired for 50 seconds at 400 ~ 900 ℃ using a belt-type kiln to manufacture a solar cell.

( 1) Contact resistance

The contact resistance (Rc) of the cell prepared as described above was measured using a cell printed with a finger bar of 1 cm * 2.0 cm using a contact resistance measuring device (GP 4-TEST Pro.).

( 2) wire resistance

The line resistance (R _L ) of the cell manufactured as described above was measured using a resistance measuring instrument (keithley 2200) to measure the resistance of the finger bar 3cm in the dark room.

( 3) seal  burglar

Flux was applied to the electrode of the cell prepared as described above, and then bonded to a ribbon at 300 to 400 ° C. using a soldering iron (HAKKO). Then, the tensile strength (N / mm) was measured at a stretch rate of 50 mm / min using a tensioner (Tinius olsen, Inc.) at 180 ° peel angle. Preferably, the tensile strength may be 3.7 N / mm or more, for example, 3.7 N / mm to 5.0 N / mm. In the above range, the electrode reliability may be good.

( 4) Open Voltage

The open voltage (voc) of the manufactured test cell was measured using a solar cell efficiency measuring apparatus (Passan, CT-801).

Example Comparative example One 2 3 4 One 2 3 4 5 6 Glass
Frit
(weight%)






A1 2.0 - 2.0 - 3.0 - - - 2.0 2.0 A2 - 2.0 - 2.0 - - - - - - A3 - - - - - - 2.0 - - - A4 - - - - - - - 2.0 - - B1 1.0 1.0 - - - 3.0 1.0 1.0 - - B2 - - 1.0 1.0 - - - - - - B3 - - - - - - - - 1.0 - B4 - - - - - - - - - 1.0 Contact resistance 0.30 0.30 0.29 0.31 0.27 0.64 0.36 0.39 0.36 0.42 Wire resistance 0.34 0.35 0.33 0.35 0.28 0.49 0.39 0.37 0.35 0.38 The tensile strength
(N / mm) 3.9 3.8 4.5 4.2 2.7 4.5 4.0 4.1 3.5 3.9 Open voltage (mV) 628.4 632.1 628.9 631.3 624.8 632.3 628.7 627.1 629.3 628.2

As shown in Table 3, the composition for forming a solar cell electrode of the present invention can be seen that the electrical properties are good as the contact resistance and wire resistance is low and the open voltage is high, the tensile strength is also excellent.

On the other hand, Comparative Example 1, which does not include the second glass frit of the present invention and includes only the first glass frit, showed low tensile strength and an open voltage, and did not include the first glass frit of the present invention. Comparative Example 2 containing only the glass frit showed a result that the contact resistance is increased. In addition, it can be seen that in Comparative Examples 3 to 6 including the glass frit out of the melting temperature of the present invention, all the characteristics are inferior to Example 2.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (9)

Conductive powder, glass frit and organic vehicle,
The glass frit includes a mixture of a first glass frit having a melting temperature (Tm) of 400 ° C to 600 ° C or less and a second glass frit having a melting temperature of 650 ° C to 800 ° C. As a composition,
The first glass frit is a tellurium-bismuth-based glass frit containing tellurium (Te) and bismuth (Bi) elements,
The second glass frit is a tellurium-bismuth-tungsten-based glass frit containing tellurium (Te), bismuth (Bi) and tungsten (W) elements,
The second glass frit includes 5 mol% to 20 mol% of tellurium, 10 mol% to 30 mol% of bismuth, and 7 mol% to 15 mol% of tungsten,
The first glass frit is 0.5 wt% to 10 wt%, and the second glass frit is 0.1 wt% to 5 wt% of the total weight of the composition for forming a solar cell electrode, the composition for forming a solar cell electrode.
delete The method of claim 1,
The first glass frit is zinc (Zn), lead (Pb), phosphorus (P), germanium (Ge), gallium (Ga), cerium (Ce), iron (Fe), lithium (Li), silicon (Si) , Tungsten (W), magnesium (Mg), cesium (Cs), strontium (Sr), molybdenum (Mo), titanium (Ti), tin (Sn), indium (In), vanadium (V), barium (Ba) , Nickel (Ni), copper (Cu), sodium (Na), potassium (K), arsenic (As), cobalt (Co), zirconium (Zr), manganese (Mn), aluminum (Al) and their oxides Further comprising at least one element selected from the group consisting of, the composition for forming a solar cell electrode.
delete The method of claim 1,
The first glass frit and the second glass frit are included in a weight ratio of 6: 1 to 1: 1, the composition for forming a solar cell electrode.
delete The method of claim 1,
The composition is
60 wt% to 95 wt% of the conductive powder,
1 wt% to 20 wt% of the glass frit,
A composition for forming a solar cell electrode, comprising the remaining amount of the organic vehicle.
The method of claim 1,
The composition further comprises at least one additive of a dispersant, thixotropic agent, plasticizer, viscosity stabilizer, antifoaming agent, pigment, UV stabilizer, antioxidant, coupling agent, the composition for forming a solar cell electrode.
An electrode formed of the composition for forming a solar cell electrode according to any one of claims 1, 3, 5, 7, and 8.

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