Patent · US Expired

Transistors and manufacture thereof

US4339768A · kind A · utility

15Cited by
8References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 18, 1980
Grant dateJul 13, 1982
Priority date
Expiry dateJan 18, 2000

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/14
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

An improved transistor, an improved lead frame for use in transistor manufacture, and manufacturing methods for transistors are disclosed. The improved transistor lead frame has a premolded housing thereon which covers a substantial portion of the chip-mounting surface of the transistor heat sink. A chip-receiving cavity is provided in the molded housing which extends to the chip-receiving surface and conforms to the shape of the chip. Solder-receiving bays or bins extend laterally from the cavity to receive excess solder during bonding of the chip to the lead frame. The premolded housing surrounds the chip after it is bonded to the lead frame and when the conductors from the transistor leads to the chip are bonded in place, the housing protects these leads during subsequent handling. The hollow interior of the housing is filled with a silicone gel which encapsulates the conductors in the housing and a harder insulating material, such as epoxy, is applied over the gel.

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