Conductive compositions and processes for use in the manufacture of semiconductor devices: Mg-containing additive
View Patent ↗Described herein are a silicon semiconductor device and a conductive silver paste for use in the front side of a solar cell device.
1. A thick film composition comprising:
a) an electrically conductive material selected from the group consisting of silver metal, silver oxide, silver salts and mixtures thereof;
b) glass frit comprising 0.1-8 wt % SiO 2 , 8-25 wt % B 2 O 3 , 0-15 wt % BiF 3 and 28-85 wt % Bi 2 O 3 , based on the wt % of the total glass composition;
c) a Mg-containing additive, wherein the Mg-containing additive-is selected from the group consisting of metal oxides of Mg, any compounds that can generate metal oxides of Mg upon firing and mixtures thereof, wherein said Mg-containing additive is 0.1 wt % to 10 wt % of the total composition; and
d) an organic medium, wherein said electrically conductive material, said glass frit and said Mg-containing additive are all dispersed in said organic medium.
2. The composition of claim 1 , wherein the Mg-containing additive is MgO.
3. The composition of claim 1 , wherein the thick film composition further comprises an additional additive selected from the group consisting of: (a) a metal wherein said metal is selected from Zn, Gd, Ce, Zr, Ti, Mn, Sn, Ru, Co, Fe, Cu and Cr; (b) a metal oxide of one or more of the metals selected from Zn, Gd, Ce, Zr, Ti, Mn, Sn, Ru, Co, Fe, Cu and Cr; (c) any compounds that can generate the metal oxides of (b) upon firing; and (d) mixtures thereof.
4. The composition of claim 1 , wherein the glass frit further comprises one or more components selected from the group consisting of P 2 O 5 , GeO 2 , and V 2 O 5 .
5. The composition of claim 1 , wherein the glass frit further comprises one or more of Al 2 O 3 , CeO 2 , SnO 2 , and CaO, and wherein, based on weight percent total glass composition, the amount of Al 2 O 3 , CeO 2 , SnO 2 , and CaO is less than 6 wt %.
6. The composition of claim 5 , wherein, based on weight percent total glass composition, the amount of Al 2 O 3 , CeO 2 , SnO 2 , and CaO is less than 1.5 wt %.
7. The composition of claim 1 , wherein, based on weight percent total glass composition, the amount of BiF 3 and Bi 2 O 3 is less than 83 wt %.
8. The composition of claim 7 , wherein, based on weight percent total glass composition, the amount of BiF 3 and Bi 2 O 3 is less than 72 wt %.
9. The composition of claim 7 , wherein the glass frit further comprises Na 2 O, Li 2 O, and Ag 2 O, wherein, based on weight percent total glass composition, the amount of (Bi 2 O 3 +BiF 3 )/(Na 2 O+Li 2 O+Ag 2 O) is greater than 14.
10. The composition of claim 1 , wherein the glass frit further comprises Na 2 O, Li 2 O, and Ag 2 O, wherein, based on weight percent total glass composition, the amount of Na 2 O, Li 2 O, and Ag 2 O is less than 5 wt %.
11. The composition of claim 10 , wherein, based on weight percent total glass composition, the amount of Na 2 O, Li 2 O, and Ag 2 O is less than 2.0 wt %.
12. The composition of claim 1 , wherein the glass frit further comprises one or both of Al 2 O 3 and B 2 O 3 , wherein, based on weight percent total glass composition, the amount of SiO 2 , Al 2 O 3 , and B 2 O 3 is less than 31 wt %.
13. A structure comprising:
(i) a thick film composition comprising:
a) an electrically conductive material selected from the group consisting of silver metal, silver oxide, silver salts and mixtures thereof;
b) glass frit comprising 0.1-8 wt % SiO 2 , 8-25 wt % B 2 O 3 , 0-15 wt % BiF 3 and 28-85 wt % Bi 2 O 3 , based on the wt % of the total glass composition;
c) a Mg-containing additive, wherein the Mg-containing additive-is selected from the group consisting of metal oxides of Mg, any compounds that can generate metal oxides of Mg upon firing and mixtures thereof, wherein said Mg-containing additive is 0.1 wt % to 10 wt % of the total composition; and
d) an organic medium, wherein said electrically conductive material, said glass frit and said Mg-containing additive are all dispersed in said organic medium;
(ii) one or more substrates; and
(iii) one or more insulating films,
wherein, upon firing, the organic medium is removed and the glass frit and silver powder are sintered, and wherein the structure is a semiconductor device.
14. The structure of claim 13 , wherein the Mg-containing additive is MgO.
15. The structure of claim 13 , wherein, upon firing, the one or more insulating films are penetrated by components of the thick film composition.
16. The structure of claim 13 , wherein the semiconductor device is a solar cell.
17. The structure of claim 16 , wherein the insulating film comprises one or more components selected from: titanium oxide, silicon nitride, SiNx:H, silicon oxide, and silicon oxide/titanium oxide.
18. The structure of claim 17 , wherein, upon firing, the one or more insulating films is penetrated by components of the thick film composition.
19. The structure of claim 13 , wherein the thick film composition further comprises an additional additive selected from the group consisting of: (a) a metal wherein said metal is selected from Zn, Gd, Ce, Zr, Ti, Mn, Sn, Ru, Co, Fe, Cu and Cr; (b) a metal oxide of one or more of the metals selected from Zn, Gd, Ce, Zr, Ti, Mn, Sn, Ru, Co, Fe, Cu and Cr; (c) any compounds that can generate the metal oxides of (b) upon firing; and (d) mixtures thereof.
20. The structure of claim 13 , wherein the glass frit further comprises one or more components selected from the group consisting of P 2 O 5 , GeO 2 , and V 2 O 5 .
21. The structure of claim 13 , wherein the one or more insulating films comprise one or more components selected from: titanium oxide, silicon nitride, SiNx:H, silicon oxide, and silicon oxide/titanium oxide.
22. The structure of claim 13 , wherein the glass frit further comprises one or more of Al 2 O 3 , CeO 2 , SnO 2 , and CaO, wherein, based on weight percent total glass composition, the amount of Al 2 O 3 , CeO 2 , SnO 2 , and CaO is less than 6 wt %.
23. The structure of claim 22 , wherein, based on weight percent total glass composition, the amount of Al 2 O 3 , CeO 2 , SnO 2 , and CaO is less than 1.5 wt %.
24. The structure of claim 22 , wherein the glass frit further comprises one or more of Na 2 O, Li 2 O, and Ag 2 O, wherein, based on weight percent total glass composition, the amount of Na 2 O, Li 2 O, and Ag 2 O is less than 5 wt %.
25. The structure of claim 22 , wherein the glass frit further comprises one or both of Al 2 O 3 and B 2 O 3 , wherein, based on weight percent total glass composition, the amount of SiO 2 , Al 2 O 3 , and B 2 O 3 is less than 31 wt %.
26. The structure of claim 13 , wherein based on weight percent total glass composition, the amount of BiF 3 and Bi 2 O 3 is less than 83 wt %.
27. The structure of claim 26 , wherein, based on weight percent total glass composition, the amount of BiF 3 and Bi 2 O 3 is less than 72 wt %.
28. The structure of claim 26 , wherein the glass frit further comprises one or more of Al 2 O 3 , CeO 2 , SnO 2 , and CaO, wherein, based on weight percent total glass composition, the amount of Al 2 O 3 , CeO 2 , SnO 2 , and CaO is less than 6 wt %.
29. The structure of claim 26 , wherein the glass frit further comprises one or more of Na 2 O, Li 2 O, and Ag 2 O, wherein, based on weight percent total glass composition, the amount of Na 2 O, Li 2 O, and Ag 2 O is less than 5 wt %.
30. The structure of claim 13 , wherein the glass frit further comprises one or more of Na 2 O, Li 2 O, and Ag 2 O, wherein, based on weight percent total glass composition, the amount of Na 2 O, Li 2 O, and Ag 2 O is less than 5 wt %.
31. The structure of claim 30 , wherein, based on weight percent total glass composition, the amount of Na 2 O, Li 2 O, and Ag 2 O is less than 2.0 wt %.
32. The structure of claim 30 , wherein, based on weight percent total glass composition, the amount of (Bi 2 O 3 +BiF 3 )/(Na 2 O+Li 2 O+Ag 2 O) is greater than 14.
33. The structure of claim 30 , wherein the glass frit further comprises one or both of Al 2 O 3 and B 2 O 3 , wherein, based on weight percent total glass composition, the amount of SiO 2 , Al 2 O 3 , and B 2 O 3 is less than 31 wt %.
34. The structure of claim 13 , wherein the glass frit further comprises one or both of Al 2 O 3 and B 2 O 3 , wherein, based on weight percent total glass composition, the amount of SiO 2 , Al 2 O 3 , and B 2 O 3 is less than 31 wt %.