Granted Patent B2

US 9,397,252 · App. 14/594,439 · Granted Jul 19, 2016

Abstract

Claims (62)

1. A method comprising:

forming a first metallization pattern along a first outside edge of a first surface of a semiconductor wafer;

forming a second metallization pattern along a second outside edge of the first surface, the second outside edge opposite to the first outside edge; and

forming a first scribe line between the first metallization pattern and the second metallization pattern;

wherein:

the first metallization pattern comprises a first finger pointing toward the second metallization pattern;

the second metallization pattern comprises a second finger pointing toward the first metallization pattern;

the first metallization pattern further comprises a first bus bar intersecting the first finger and located within 5 mm of the first outside edge; and

the second metallization pattern comprises a second bus bar intersecting the second finger and located within 5 mm of the second outside edge.

2. A method as in claim 1 further comprising:

forming on the first surface, a third metallization pattern not along the first outside edge or along the second outside edge, the third metallization pattern comprising,

a third bus bar parallel to the first bus bar, and

a third finger pointing toward the second metallization pattern; and

forming a second scribe line between the third metallization pattern and the second metallization pattern, wherein the first scribe line is between the first metallization pattern and the third metallization pattern.

3. A method as in claim 2 wherein the first scribe line and the second scribe line are separated by a width having a ratio to a length of the semiconductor wafer, of between about 1:2 to about 1:20.

4. A method as in claim 3 wherein the length of the semiconductor wafer is about 156 mm or about 125 mm.

5. A method as in claim 2 wherein the semiconductor wafer includes chamfered corners.

6. A method as in claim 5 wherein:

the first scribe line defines with the first outside edge, a first solar cell region comprising two chamfered corners and the first metallization pattern, the first solar cell region having a first area corresponding to a product of a length of the semiconductor wafer and a first width, minus a combined area of the two chamfered corners; and

the second scribe line defines with the first scribe line, a second solar cell region not including chamfered corners and including the third metallization pattern, the second solar cell region having a second area corresponding to a product of the length and a second width narrower than the first width, such that the first area and the second area are approximately the same.

7. A method as in claim 6 wherein the length is about 156 mm or about 125 mm.

8. A method as in claim 2 wherein forming the first scribe line and forming the second scribe line comprise laser scribing.

9. A method as in claim 2 wherein forming the first metallization pattern, forming the second metallization pattern, and forming the third metallization pattern, comprise printing.

10. A method as in claim 9 wherein forming the first metallization pattern, forming the second metallization pattern, and forming the third metallization pattern, comprise screen printing.

11. A method as in claim 9 wherein forming the first metallization pattern comprises forming a plurality of contact pads comprising silver.

12. A method as in claim 2 wherein forming the first metallization pattern, forming the second metallization pattern, and forming the third metallization pattern, comprise electroplating.

13. A method as in claim 12 wherein the first metallization pattern, the second metallization pattern, and the third metallization pattern comprise copper.

14. A method as in claim 2 wherein the first metallization pattern comprises one or more of aluminum, tin, silver, and copper.

15. A method as in claim 2 wherein the semiconductor wafer comprises silicon.

16. A method as in claim 15 wherein the semiconductor wafer comprises crystalline silicon.

17. A method as in claim 2 further comprising forming a fourth metallization pattern on a second surface of the semiconductor wafer between the first outside edge and within 5 mm of a location of the second scribe line.

18. A method as in claim 17 wherein the first surface comprises a first conductivity type and the second surface comprises a second conductivity type opposite to the first conductivity type.

19. A method as in claim 17 wherein the fourth metallization pattern comprises a contact pad.

20. A method as in claim 1 further comprising applying a conductive adhesive to the semiconductor wafer.

21. A method as in claim 20 further comprising applying the conductive adhesive in contact with the first finger.

22. A method as in claim 21 wherein applying the conductive adhesive comprises screen printing or depositing utilizing a mask.

23. A method as in claim 1 further comprising separating the semiconductor wafer along the first scribe line to form a first solar cell strip including the first metallization pattern.

24. A method as in claim 23 wherein the separating comprises applying a vacuum to the semiconductor wafer along the first scribe line.

25. A method as in claim 24 further comprising disposing the semiconductor wafer on a belt moving to the vacuum.

26. A method as in claim 23 further comprising applying a conductive adhesive to the first solar cell strip.

27. A method as in claim 23 further comprising:

arranging the first solar cell strip in a first super cell comprising at least nineteen solar cell strips each having a breakdown voltage of at least 10V, with long sides of adjacent solar cell strips overlapping with conductive adhesive disposed in between; and

curing the conductive adhesive to bond adjacent overlapping solar cell strips electrically connected in series.

28. A method as in claim 27 wherein the arranging comprises forming a layered structure including an encapsulant, the method further comprising laminating the layered structure.

29. A method as in claim 28 wherein the curing occurs at least partially during the laminating.

30. A method as in claim 28 wherein the curing occurs distinct from the laminating.

31. A method as in claim 28 wherein the encapsulant comprises a thermoplastic olefin polymer.

32. A method as in claim 28 wherein the layered structure comprises:

a white backing sheet; and

darkened stripes on the white backing sheet.

33. A method as in claim 27 wherein the arranging comprises confining a spreading of the conductive adhesive with a metallization pattern feature.

34. A method as in claim 33 wherein the metallization pattern feature is on a front surface of the first solar cell strip.

35. A method as in claim 27 further comprising applying the conductive adhesive between the first super cell and an interconnect connecting a second super cell in series.

36. A method as in claim 27 further comprising connecting a ribbon conductor between a single bypass diode and the first super cell, the single bypass diode located in a first junction box of a first solar module in mating arrangement with a second junction box of a second solar module.

37. A method as in claim 27 wherein:

the first solar cell strip includes a first chamfered corner;

a long side of an overlapping solar cell strip of the first super cell does not include a second chamfered corner; and

a width of the first solar cell strip is greater than a width of the overlapping solar cell strip, such that the first solar cell strip and the overlapping solar cell strip have approximately a same area.

38. A method as in claim 27 wherein:

the first solar cell strip includes a first chamfered corner;

a long side of an overlapping solar cell strip of the first super cell includes a second chamfered corner; and

the long side of the overlapping solar cell strip overlaps a long side of the first solar cell strip not including the first chamfered corner.

Assignments (6)