EUTECTIC BOND AND METHOD OF GOLD/TITANIUM EUTECTIC BONDING OF CADMIUM TELLURIDE TO SAPPHIRE

Abstract

A method of forming a eutectic bond, of Cadmium Telluride to Sapphire utilizing the Gold/Silicon eutectic bonding of the Cadmium Telluride to the Sapphire. A multi-layer structure of: Chromium which provides adhesion to the Cadmium Telluride; a Titanium layer which functions as a diffusion barrier to the Gold, and a Gold layer are sequentially evaporated on the Cadmium Telluride; a separate multilayered structure of: Silicon grown on Sapphire, and Gold evaporated upon the Silicon. These two multilayered structures are then eutectically bonded. This method enables the expansion coefficient of the eutectic layer to be tailored through the Gold concentration to match that of the Cadmium Telluride. This method also allows the bonding stress to be confined between the Gold/Silicon eutectic and the Sapphire substrate, eliminating the bonding stress in the Cadmium Telluride. Also, due to the precision of the thickness of the evaporated layers, the bonded substrates are inherently planar and parallel.

Source: Google Patents

35 USC §181 Secrecy Order

Inventor

• 1RICHARD C. MC KEE