Patent ID: 6189766
Filing Date: 2001-02-20
Classification: H01L,Y10T

Abstract:
A process for bonding together a silicon carbide layer and a diamond layer, yielding a composite structure which is substantially stress-free at a selectable reference temperature and reference isostatic pressure, comprising the steps of:(a) providing the silicon carbide layer and the diamond layer;(b) determining a critical line for the silicon carbide layer and the diamond layer in a pressure-temperature plane wherein a location of the critical line depends on the selectable reference temperature and reference isostatic pressure and depends on coefficients of thermal expansion and bulk moduli material constants of the silicon carbide layer and the diamond layer, wherein the critical line sets forth a plurality of temperature-pressure pairs at which the composite structure will be substantially stress-free;(c) controlling a temperature and an isostatic pressure during bonding such that the temperature and the isostatic pressure represent a point on the critical line;(d) bonding the silicon carbide layer and the diamond layer at the temperature and the isostatic pressure in said step (c); and(e) returning to the selectable reference temperature and reference isostatic pressure after bonding is completed by following a path along the critical line for the silicon carbide layer and the diamond layer determined in said step (b) which avoids imposing disruptive stresses on the composite structure.