Patent · US Expired

Method and apparatus for two sided solder cladded surface mounted printed circuit boards

US5167361A · kind A · utility

20Cited by
2References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 16, 1991
Grant dateDec 1, 1992
Priority date
Expiry dateMay 16, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P70/50
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of forming flat solder bumps (16 and 18) on contact areas (12 and 14) of a first side and second side of a printed circuit board (12, 14 and 10) comprises the steps of applying solder paste in a predetermined pattern and a predetermined thickness on the contact areas of the first side and the second side of the printed circuit board forming joint areas. Next, the solder paste is reflowed. Then, the solder joints on the first side are flattened (17). Before surface mounted components (20 and 26) are mounted on the printed circuit board, tack media (32) is dispensed onto the joint areas. Subsequently, the printed circuit boards is reflowed. Now the second side of the printed circuit board is flattened (19). As with the first side, tack media (34) is dispensed on the solder joints on the second side before surface mounted components (40 and 46) are mounted on the second side. Finally, the printed circuit board is reflowed again.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.