METHOD OF PRODUCING A MULTI-LAYER CONTACT METALLISATION ON A SILICON SEMICONDUCTOR COMPONENT

摘要

This method is used to apply a multilayer, high-adhesion and soft-solderable contact metallisation (7) to the highly doped surface of a silicon semiconductor component (1) and preferably finds application in power semiconductor components such as thyristors. The first layer (2) applied is a metal such as nickel which readily forms a silicide with silicon. The second layer (3) is provided by a metal such as chromium whose silicide formation proceeds appreciably more slowly than that of nickel. A metal such as nickel, which is only slightly dissolved by soft solder, follows as third layer (4). The fourth layer (5) applied is a transition layer of nickel and a noble metal and this gradually merges into a fifth layer (6), which is a protective layer of silver. Alternatively, the nickel and chromium of the first and second layer can be applied together.