Solder and packaging therefrom

• US 20060011702A1
• Filed: 07/01/2003
• Published: 01/19/2006
• Est. Priority Date: 07/04/2002
• Status: Abandoned Application

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Kubota, Hiroshi, Funaya, Takuo, Myohga, Osamu, Sakurai, Junya, Okada, Yoshitsugu
• Application Number:
  US10/516,708
• Publication Number:
  US 20060011702A1
• Time in Patent Office: Days
• US Class Current: 228/56.300
• CPC Class Codes: B23K 35/262 Sn as the principal constituent
• CPC Class Codes: H05K 3/3463 Solder compositions in relation to features of the printed circuit board or the mounting process

Abstract

The solder contains Sn—Zn alloy(s) having a single composition ratio or a plurality of composition ratios, and Sn—Bi—Ag alloy(s) having a single composition ratio or a plurality of composition ratios. The solder includes zinc at 7 to 10 weight % both inclusive, bismuth at 0.001 to 6 weight % both inclusive, silver at 0.001 to 0.1 weight % both inclusive, and the remainder of tin when the alloys are melted in mixture.

Claims

1-8. -8. (canceled)

9. A solder comprising zinc at 7 to 10 weight % both inclusive, bismuth at 0.001 to 6 weight % both inclusive, silver at 0.001 to 0.1 weight % both inclusive, and the remainder of tin.

10. The solder as set forth in claim 9, wherein said solder is in the form of powder.

11. The solder as set forth in claim 10, wherein said powder has a diameter in the range of 20 to 40 micrometers both inclusive.

12. The solder as set forth in claim 10, wherein a difference between a maximum diameter of said powder and a minimum diameter of said powder is equal to or smaller than 10 micrometer.

13. The solder as set forth in claim 10, wherein said solder is mixed in flux.

14. The solder as set forth in claim 13, wherein said flux has a concentration in the range of 9 to 13 weight % both inclusive.

15. A solder comprising Sn—

Zn alloy(s) having a single composition ratio or a plurality of composition ratios, and Sn—

Bi—

Ag alloy(s) having a single composition ratio or a plurality of composition ratios, said solder including zinc at 7 to 10 weight % both inclusive, bismuth at 0.001 to 6 weight % both inclusive, silver at 0.001 to 0.1 weight % both inclusive, and the remainder of tin when said alloys are melted in mixture.

16. The solder as set forth in claim 15, wherein said solder is in the form of powder.

17. The solder as set forth in claim 16, wherein said powder has a diameter in the range of 20 to 40 micrometers both inclusive.

18. The solder as set forth in claim 16, wherein a difference between a maximum diameter of said powder and a minimum diameter of said powder is equal to or smaller than 10 micrometer.

19. The solder as set forth in claim 16, wherein said solder is mixed in flux.

20. The solder as set forth in claim 19, wherein said flux has a concentration in the range of 9 to 13 weight % both inclusive.

21. A circuit substrate unit comprising a circuit board, and at least one electronic component soldered onto said circuit board,

wherein said electronic component is soldered onto said circuit board through a solder, and

said solder contains zinc at 7 to 10 weight % both inclusive, bismuth at 0.001 to 6 weight % both inclusive, silver at 0.001 to 0.1 weight % both inclusive, and the remainder of tin.

22. The circuit substrate unit as set forth in claim 21, wherein said solder is in the form of powder.

23. The circuit substrate unit as set forth in claim 22, wherein said powder has a diameter in the range of 20 to 40 micrometers both inclusive.

24. The circuit substrate unit as set forth in claim 22, wherein a difference between a maximum diameter of said powder and a minimum diameter of said powder is equal to or smaller than 10 micrometer.

25. The circuit substrate unit as set forth in claim 22, wherein said solder is mixed in flux.

26. The circuit substrate unit as set forth in claim 25, wherein said flux has a concentration in the range of 9 to 13 weight % both inclusive.

27. A circuit substrate unit comprising a circuit board, and at least one electronic component soldered onto said circuit board,

wherein said electronic component is soldered onto said circuit board through a solder, and

said solder contains Sn—

Zn alloy(s) having a single composition ratio or a plurality of composition ratios, and Sn—

Bi—

Ag alloy(s) having a single composition ratio or a plurality of composition ratios, said solder including zinc at 7 to 10 weight % both inclusive, bismuth at 0.001 to 6 weight % both inclusive, silver at 0.001 to 0.1 weight % both inclusive, and the remainder of tin when said alloys are melted in mixture.

28. The circuit substrate unit as set forth in claim 27, wherein said solder is in the form of powder.

29. The circuit substrate unit as set forth in claim 28, wherein said powder has a diameter in the range of 20 to 40 micrometers both inclusive.

30. The circuit substrate unit as set forth in claim 28, wherein a difference between a maximum diameter of said powder and a minimum diameter of said powder is equal to or smaller than 10 micrometer.

31. The circuit substrate unit as set forth in claim 28, wherein said solder is mixed in flux.

32. The circuit substrate unit as set forth in claim 31, wherein said flux has a concentration in the range of 9 to 13 weight % both inclusive.