A proposed narrow-band-gap base transistor structure

Abstract

A transistor structure is proposed which alleviates the problem of high base resistance in the narrow quantum-well base region of the Resonant-Tunneling Transistor (RTT). This idea may also be used to improve the performance of the Induced Base Transistor (IBT) and other related structures. Bound states are created in the quantum well by using a base material with lower band gap than the contact layers. Electrons in these bound states form a low-resistance base region for application of bias to the device. Current flow is due to resonant tunneling via the second energy level in the well. Calculated I-V curves and switching transients for the RTT are presented. The issue of undesired tunneling current from base to collector is addressed, and a modified RTT structure is proposed which significantly reduces this problem.