A practical technique for controlling field profile in thin layers of n-GaAs

A practical technique has been developed for controlling the field profile in a thin epitaxial layer of n-GaAs biased above the transferred-electron threshold. This employs a special cathode composed of an electron-injecting n⁺contact complemented by an electron-blocking (reverse-biased Schottky barrier) contact, which extends a selected distance past the n⁺contact. The situation is characterized theoretically, and potential profile measurements confirm that the desired profile can be obtained in this manner.