Reliability assurance of individual semiconductor components

Where small numbers of highly reliable semiconductor devices are required, conventional methods of procurement are found to have deficiencies. An approach to procurement is proposed which is cost effective, accommodates new device types, and assures reliability in the individual device. Although principally applied to silicon planar transistors, the approach can be extended to other semiconductor types. A critical evaluation is made of the manufacturer and his technology. The devices obtained from each diffused wafer are grouped into separate lots. Selected tests are performed on these lots in order to discover possible failure mechanisms. Tests may involve simple electrical measurements or detailed techniques such as scanning electron microscopy and X-ray microprobe analysis. The Canadian/U.S.A. Communications Technology Satellite (CTS) program has adopted this procurement procedure.