Solar cell contacts with nickel intermetallic compositions

Patent metadata

Field	Value
Publication number	US-9818890-B2
Application number	US-201314394908-A
Country	US
Kind code	B2
Filing date	Apr 18, 2013
Priority date	Apr 18, 2012
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

Paste compositions, methods of making a paste composition, and methods of making a solar cell contact are disclosed. The paste composition can contain a nickel intermetallic compound such as nickel silicide, nickely boride or nickel phosphide, a glass frit, a metal additive and an organic vehicle system. The paste can be used for making a solar cell contact.

First claim

The invention claimed is:

1. A solar cell contact comprising:
a. a crystalline silicon wafer forming a first layer of the contact;
b. an antireflective layer deposited on the silicon wafer forming a second layer of the contact,
c. a third layer of the contact comprising at least one of nickel boride and nickel phosphide deposited on at least a portion of the antireflective layer, and
d. a high-conductivity layer deposited on at least a portion of the third layer thereby forming a fourth layer of the contact, the high-conductivity layer comprising a metal selected from the group consisting of silver, silver-coated nickel, and silver-coated copper.

2. The solar cell contact of claim 1 , wherein the third layer further comprises a glass.

3. The solar cell contact of claim 1 , wherein the high-conductivity layer further comprises a glass.

4. The solar cell contact of claim 3 , wherein the high-conductivity layer comprises a glass selected from the group consisting of:
a. a glass comprising 52-88 wt % PbO, 0.5-15 wt % SiO 2 , 0.5-10 wt % Al 2 O 3 , 0-22 wt % ZnO, 0-8 wt % Ta 2 O 5 , 0-10 wt % ZrO 2 , 0-8 wt % P 2 O 5 , 0-15 wt % (Li 2 O+Na 2 O+K 2 O), 0-12 wt % B 2 O 3 , and 0-25 wt % Fe 2 O 3 +CO 2 O 3 +CuO+MnO 2 , based upon total weight of the glass,
b. a glass comprising 55-90 wt % Bi 2 O 3 , 1-15 wt % B 2 O 3 , 0-20 wt % SiO 2 , 0-13 wt % ZnO, 0-12 wt % Li 2 O, 0-12 wt % Na 2 O, 0-12 wt % K 2 O, 0-10 wt % Nb 2 O 5 +Ta 2 O 5 , and 0-25 wt % Fe 2 O 3 +Co 2 O 3 +CuO+MnO 2 , based upon total weight of the glass, and
c. a glass comprising 30-62 wt % B 2 O 3 +SiO 2 , 0-34 wt % ZnO, 0-22 wt % TiO 2 , 0-10 wt % Li 2 O, 0-23 wt % Na 2 O, 0-13 wt % K 2 O, 0-10 wt % P 2 O 5 , 0-13 wt % Sb 2 O 3 +P 2 O 5 , 0-8 wt % ZrO 2 , 0-5 wt % F, and 0-25 wt % Fe 2 O 3 +Co 2 O 3 +CuO+MnO 2 , based upon total weight of the glass.

5. A solar cell contact comprising:
a. a crystalline silicon wafer forming a first layer;
b. an antireflective layer deposited on the silicon wafer forming a second layer, and
c. a third layer deposited on at least a portion of the antireflective layer, the third layer formed from a paste comprising: (i) 65-95 wt % of a nickel intermetallic compound selected from at least one of nickel boride and nickel phosphide, (ii) 1-10 wt % of an organic vehicle, 1-10 wt % of at least one solvent, and 1-10 wt % of glass.

6. The solar cell contact of claim 5 , wherein the paste comprises 70-90 wt % of the nickel intermetallic compound.

7. The solar cell contact of claim 5 , wherein the nickel intermetallic compound is nickel boride having a particle size of 2 to 5 microns.

8. The solar cell contact of claim 5 , wherein the paste comprising a nickel intermetallic compound is a hot melt paste.

9. The solar cell contact of claim 5 , wherein the glass is selected from the group consisting of:
a. a glass comprising 52-88 wt % PbO, 0.5-15 wt % SiO 2 , 0.5-10 wt % Al 2 O 3 , 0-22 wt % ZnO, 0-8 wt % Ta 2 O 5 , 0-10 wt % ZrO 2 , 0-8 wt % P 2 O 5 , 0-15 wt % (Li 2 O+Na 2 O+K 2 O), 0-12 wt % B 2 O 3 , and 0-25 wt % Fe 2 O 3 +CO 2 O 3 +CuO+MnO 2 , based upon total weight of the glass,
b. a glass comprising 55-90 wt % Bi 2 O 3 , 1-15 wt % B 2 O 3 , 0-20 wt % SiO 2 , 0-13 wt % ZnO, 0-12 wt % Li 2 O, 0-12 wt % Na 2 O, 0-12 wt % K 2 O, 0-10 wt % Nb 2 O 5 +Ta 2 O 5 , and 0-25 wt % Fe 2 O 3 +Co 2 O 3 +CuO+MnO 2 , based upon total weight of the glass, and
c. a glass comprising 30-62 wt % B 2 O 3 +SiO 2 , 0-34 wt % ZnO, 0-22 wt % TiO 2 , 0-10 wt % Li 2 O, 0-23 wt % Na 2 O, 0-13 wt % K 2 O, 0-10 wt % P 2 O 5 , 0-13 wt % Sb 2 O 3 +P 2 O 5 , 0-8 wt % ZrO 2 , 0-5 wt % F, and 0-25 wt % Fe 2 O 3 +Co 2 O 3 +CuO+MnO 2 , based upon total weight of the glass.

10. The solar cell contact of claim 5 , wherein the paste comprises 78-82 wt % of the nickel intermetallic compound, 3-6 wt % of the organic vehicle, 2-4 wt % of the at least one solvent, and 2-6 wt % of the glass.

11. The solar cell contact of claim 5 , wherein the paste further includes a crystalline additive comprising Bi 2 O 3 , ZrO 2 , or a combination thereof.

Assignees

• Heraeus Precious Metals North America Conshohocken Llc
• Ferro Corp

Inventors

• Khatri Himal
• Shaikh Aziz S
• Sridharan Srinivasan
• Kunze Klaus

Classifications

• Y02E10/50

  Photovoltaic [PV] energy · CPC title

• H01L31/02245

  Electricity · mapped topic

• H01L31/022425 Primary

  Electricity · mapped topic

• H01L31/02168

  Electricity · mapped topic

• H01B1/22 Primary

  the conductive material comprising metals or alloys · CPC title