Patent · US Expired

Oxide-free extruded thermal joint

US4685606A · kind A · utility

10Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 9, 1986
Grant dateAug 11, 1987
Priority date
Expiry dateMay 9, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/01014
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method of joining a thermally conductive element to an electric circuit chip for cooling the chip includes initial steps of forming an oxide-free preform of a fusible metal alloy by extrusion of alloy between two mold blocks or plates. During the extrusion, the oxide coating is left behind so that the extruded alloy is essentially free of oxide. The extrusion takes place at a temperature elevated to approximately the liquidus temperature of the alloy. The preform, which may be in the form of a pill or section of thin foil, is placed between interfacing surfaces of the thermally conductive element and the chip, and is then extruded along the interfacing surfaces under pressure and elevated temperature to form a thermally conductive, oxide-free bonding layer of superior thermal conductivity.

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