Patent · US Expired

Anti-tombstoning structures and methods of manufacture

US6566611B2 · kind B2 · utility

26Cited by
14References
32Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 26, 2001
Grant dateMay 20, 2003
Priority date
Expiry dateSep 26, 2021

Classification

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

Abstract

A substrate, such as a printed circuit board (PCB), has pairs of pads to which terminals of electronic components, such as capacitors, can be mounted. The pads have perimeters, for example, in the shape of rectangles, circles, or ovals. In one embodiment, to reduce asymmetrical, lateral, surface-tension forces that can cause the components to tombstone due to uneven heating of solder fillets on the pads during solder reflow, the edge of the perimeter of each pad opposite the inter-pad region contains one or more notches or indentations. Also described are an electronic assembly, an electronic system, and various methods of fabrication.

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