Method of forming bumps
US6413850B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 2000 |
| Grant date | Jul 2, 2002 |
| Priority date | — |
| Expiry date | Aug 18, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/3478
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention provides a method of forming bumps capable of forming many bumps having an adequate volume and having a narrow range of variations in height and few limitations in selecting materials on an object such as a semiconductor device or the like at high production rates with high reliability and with ease, and a system therefor. The present invention uses a suction head using a porous plate and a stencil having many apertures. Solder balls are previously aligned and charged into the stencil. The solder balls and the stencil are sucked and retained by the suction head and then are positioned with respect to the surfaces of the pads of a semiconductor device and only the solder balls are dropped on the pads. The solder balls are fixed to the pads with an adhesive previously applied thereto and then are reflowed to form bumps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.