Graded Barrier in Tunnelling Hot Electron Transfer Amplifiers
Original Publication Date: 1989-Jan-01
Included in the Prior Art Database: 2005-Jan-27
A technique is described whereby the operational performance of tunnelling hot electron transfer amplifiers (THETA) is improved by grading the barrier of the collector barrier so as to reduce the blocking potential of incoming electrons. Typically, the collector barrier of THETA devices is made of AlGaAs, with a constant composition of Al, and has the shape of a square type potential in space. A typical transfer of electron flow for a square type barrier is shown in Fig. 1. In theory, the device can operate with zero voltage applied across the barrier; however, for large output voltage swings, the collector polarity will be reversed. This causes a blocking barrier for the hot (Image Omitted) or ballistic electrons.