Composition for forming solar cell electrode and electrode prepared using the same
A composition for solar cell electrodes includes a conductive powder, a glass frit, and an organic vehicle. The glass frit contains about 20 mol % to about 40 mol % of an alkali metal, about 20 mol % to about 30 mol % of zinc (Zn), and about 7 mol % to about 20 mol % of magnesium (Mg) in terms of oxide content.
1. A composition for solar cell electrodes, comprising:
a conductive powder;
a glass frit; and
an organic vehicle,
wherein the glass frit contains about 20 mol % to about 40 mol % of an alkali metal, about 20 mol % to about 30 mol % of zinc (Zn), and about 7 mol % to about 20 mol % of magnesium (Mg) in terms of oxide content, and
wherein the glass frit further contains tellurium and satisfies Equation 1:
0.4≤(M Zn +M AL )/M Te ≤4.0 [Equation 1]
where M zn denotes mol % of zinc, M AL denotes mol % of the alkali metal, and M Te denotes mol % of tellurium, as measured in terms of oxide content.
2. The composition according as claimed in claim 1 , wherein a molar ratio of the alkali metal to magnesium (Mg) ranges from about 1:1 to about 6:1 in terms of oxide content.
3. The composition according as claimed in claim 1 , wherein the alkali metal includes at least one of lithium (Li), sodium (Na), and potassium (K).
4. The composition according as claimed in claim 1 , wherein the glass frit includes at least one of a lead (Pb)-tellurium (Te)-alkali metal-zinc (Zn)-magnesium (Mg)-oxygen (O) glass frit, a bismuth (Bi)-tellurium (Te)-alkali metal-zinc (Zn)-magnesium (Mg)-oxygen (O) glass frit, and a lead (Pb)-bismuth (Bi)-tellurium (Te)-alkali metal-zinc (Zn)-magnesium (Mg)-oxygen (O) glass frit.
5. The composition according as claimed in claim 1 , wherein the glass frit further contains boron (B).
6. The composition according as claimed in claim 1 , comprising:
about 67.5 wt % to about 96.5 wt % of the conductive powder;
about 0.1 wt % to about 20 wt % of the glass frit; and
about 1 wt % to about 30 wt % of the organic vehicle.
7. The composition according as claimed in claim 6 , wherein the glass frit is present in an amount of about 0.1 wt % to about 3.0 wt % in the composition for solar cell electrodes.
8. The composition according as claimed in claim 1 , further comprising: at least one additive selected from a dispersant, a thixotropic agent, a plasticizer, a viscosity stabilizer, an anti-foaming agent, a pigment, a UV stabilizer, an antioxidant, and a coupling agent.
9. A solar cell electrode fabricated using the composition for solar cell electrodes according to claim 1 .