Methods for soldering semiconductor devices
US5082162A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 1991 |
| Grant date | Jan 21, 1992 |
| Priority date | — |
| Expiry date | Feb 5, 2011 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K35/26
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
This invention presents a new soldering material comprising an indium layer formed on EFTE film for solder-mounting a semiconductor device onto a metal heat sink. This indium layer can be easily transferred onto the heat sink by pressure applied by a tool, without the aid of ultrasonic energy. This produces a highly immaculate surface of the indium layer transferred onto the heat sink, and achieves stable soldering strength of the soldered semiconductor device. This invention also offers a multi-layered soldering material comprising a thin layer of metal of which the melting point is higher than the soldering temperature, and two indium layers sandwiching said metal layer, formed on an EFTE film. This multi-layered soldering material can be easily transferred onto a metal heat sink by a pressure applying tool without the aid of ultrasonic energy resulting in the stable soldering of a semiconductor device even if it has surface irregularities, without causing an electrical leakage or short circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.