Paste for Contacts and Solar Cell Using the Same

• US 20130133742A1
• Filed: 08/09/2011
• Published: 05/30/2013
• Est. Priority Date: 08/10/2010
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Kim, Sang Gon, Lee, In Jae, Kim, Soon Gil, Park, Jin Gyeong
• Granted Patent: US 9,911,519 B2
• Time in Patent Office: Days
• US Class Current: 136/256
• CPC Class Codes: C01G 15/00 Compounds of gallium, indium or thallium
• CPC Class Codes: C01G 3/00 Compounds of copper
• CPC Class Codes: C01G 3/006 Compounds containing, besides copper, two or more other elements, with the exception of oxygen or hydrogen
• CPC Class Codes: C01G 30/02 Antimonates; Antimonites C01G30/001 takes precedence
• CPC Class Codes: C01G 49/0018 Mixed oxides or hydroxides, C01G49/0009 takes precedence
• CPC Class Codes: H01B 1/023 Alloys based on aluminium
• CPC Class Codes: H01B 1/16 the conductive material comprising metals or alloys
• CPC Class Codes: H01L 31/0224 Electrodes
• CPC Class Codes: H01L 31/022425 for solar cells
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

Provided are a paste for contacts and a solar cell using the same. The paste for contacts includes Al powder, glass frit, inorganic binder, and P-type oxidation containing I group elements.

Claims

1. A paste for contacts comprising Al powder, glass frit, inorganic binder, and P-type oxidation containing I group elements.

2. The paste according to claim 1, wherein the P-type oxidation additionally comprises alkaline earth metals, transition elements, III group elements, or V group elements.

3. The paste according to claim 1, wherein the P-type oxidation is expressed as following Chemical Formula 1.

A_XB_YO_Z 

 

[Chemical Formula 1]

(where, 0.5<

X≦

1.5, 0.5<

Y≦

2.5, 1.5<

Z≦

4.5, A is one selected from Cu and Ag, and B is one selected from a group consisting of B, Al, Ga, In, Ti, Mn, Y, La, Fe, Cr, Sb, Sc, Nd, and Bi)

4. The paste according to claim 1, wherein the P-type oxidation is expressed as following Chemical Formula 2.

Sr_1-xM_xCU_YO_Z 

 

[Chemical Formula 2]

(where, 0.03<

X≦

0.2, 1.5<

Y≦

2.5, 1.5<

Z≦

2.5, and M is one selected from a group consisting of K, Na, and Ca)

5. The paste according to claim 1, wherein the content of the P-type oxidation is a range of about 0.1 parts by weight to about 5 parts by weight, based on the total amount of the paste.

6. The paste according to claim 1, wherein the paste for contacts comprises a paste for solar cell rear contacts.

7. A solar cell comprising:

a front contact disposed on one surface of a semiconductor substrate;

a back surface field (BSF) layer disposed on the other surface of the semiconductor substrate; and

a rear contact disposed on the BSF layer,

wherein the BSF layer or the rear contact comprises a P-type oxidation containing I group elements.

8. The solar cell according to claim 7, wherein the P-type oxidation is expressed as following Chemical Formula 1.

A_xB_YO_Z 

 

[Chemical Formula 1]

(where, 0.5<

X≦

1.5, 0.5<

Y≦

2.5, 1.5<

Z≦

4.5, A is one selected from Cu and Ag, and B is one selected from a group consisting of B, Al, Ga, In, Ti, Mn, Y, La, Fe, Cr, Sb, Sc, Nd, and Bi)

9. The solar cell according to claim 7, wherein the P-type oxidation is expressed as following Chemical Formula 2.

Sr_1-xM_xCU_YO_Z 

 

[Chemical Formula 2]

(where, 0.03<

X≦

0.2, 1.5<

Y≦

2.5, 1.5<

Z≦

2.5, and M is one selected from a group consisting of K, Na, and Ca)

10. The solar cell according to claim 7, wherein each of the BSF layer and the rear contact comprises the P-type oxidation.

11. The solar cell according to claim 7, wherein the BSF layer has a thickness of about 4 μ

m to about 10 μ

m.

12. The solar cell according to claim 7, further comprising an anti-reflective layer on the semiconductor substrate.

13. A method of manufacturing a solar cell, the method comprising:

forming a paste for contacts comprising a P-type oxidation containing I group elements on the other surface of a semiconductor substrate;

forming a front contact on one surface of the semiconductor substrate; and

thermally treating the paste and the front contact to form a rear contact and a BSF layer on the other surface of the semiconductor substrate at the same time.

14. The method according to claim 13, wherein the P-type oxidation is expressed as following Chemical Formula 1.

A_xB_YO_Z 

 

[Chemical Formula 1]

(where, 0.5<

X≦

1.5, 0.5<

Y≦

2.5, 1.5<

Z≦

4.5, A is one selected from Cu and Ag, and B is one selected from a group consisting of B, Al, Ga, In, Ti, Mn, Y, La, Fe, Cr, Sb, Sc, Nd, and Bi)

15. The method according to claim 13, wherein the P-type oxidation is expressed as following Chemical Formula 2.

Sr_1-xM_xCU_YO_Z 

 

[Chemical Formula 2]

(where, 0.03<

X≦

0.2, 1.5<

Y≦

2.5, 1.5<

Z≦

2.5, and M is one selected from a group consisting of K, Na, and Ca)

16. The method according to claim 13, wherein the content of the P-type oxidation is a range of about 0.1 parts by weight to about 5 parts by weight, based on the total amount of the paste.

17. The method according to claim 13, wherein the forming of the paste comprising:

synthesizing the P-type oxidation;

adding the P-type oxidation into with an Al paste

mixing the P-type oxidation with the Al paste to form a mixture; and

milling the mixture of the P-type oxidation and the Al paste.