Self-Aligning Base Contacts in Tunneling Hot Electron Transfer Amplifier Semiconductor Devices
Original Publication Date: 1988-Sep-01
Included in the Prior Art Database: 2005-Feb-15
A technique is described whereby a method of self-alignment of base contacts in the emitter structure of tunneling hot electron transfer amplifier (THETA) semiconductor devices help reduce parasitic resistances. (Image Omitted) The method used to provide self-alignment of the base contacts in the emitter structure of THETA devices takes advantage of the crystal- lographic etching behavior of epitaxial GaAs, so as to create an emitter structure in the shape of an inverted triangle, as shown in Fig. 1. To accomplish this, the emitter must be aligned along the (011) axis. The fabrication process, as shown in Fig. 2, is performed either through wet chemical etching or through reactive ion etching (RIE).