RF performance of a novel all ternary InAlAs\InGaAs DHBT

Abstract

All ternary In 0.52 Al 0.48 As-In 0.53 Ga 0.47 As-In 0.52 Al 0.48 As double-heterojunction bipolar transistors (DHBTs) have been grown using solid-source molecular-beam epitaxy. The development of these DHBTs required epitaxial design trade-offs which culminated in an optimum structure achieving high-breakdown (5.5 V), and RF performance demonstrating unity cutoff frequency (f t) and maximum oscillation frequency (f max) of 140 GHz and 95 GHz at relatively relaxed emitter dimensions of ∼1 × 5 μm 2. This is the highest reported cutoff frequency for an all ternary In 0.52 Al 0.48 As-In 0.53 Ga 0.47 As-In 0.52 Al 0.48 As DHBT. The demonstration of the frequency performance at relaxed emitter dimensions shows potential for this material type.