Voltage variable resistor from HBT epitaxial layers

摘要

A voltage variable resistor formed on heterojunction bipolar transistor epitaxial material includes a current channel made on emitter material. Emitter mesas separated by a recess provide the contacts for the voltage variable resistor. Each mesa is topped with emitter metal forming the resistor contacts. The emitter mesas are layered on top of the current channel that is layered atop of a base layer. The voltage variable resistor's control contact is provided by a base contact located on the base layer and separated from the current channel.