A semiconductor device package is disclosed, which comprises: a substrate of AlN with said semiconductor device affixed to it; a barrier layer of high melting point glass affixed to said substrate around said semiconductor device; a first layer of low melting point glass affixed to said barrier layer;...http://www.google.com/patents/US5159432?utm_source=gb-gplus-sharePatent US5159432 - Semiconductor device package having improved sealing at the aluminum nitride substrate/low melting point glass interface
