Observation of Bloch conduction perpendicular to interfaces in a superlattice bipolar transistor

Abstract

We report the first operating bipolar transistor built with an AlGaAs/GaAs superlattice base. High current gain is measured with a suitable design of the bipolar transistor structure. Experimental results are in good agreement with a Bloch to hopping transition which is very sensitive to the AlGaAs barrier thickness. This interpretation is supported by a detailed numerical simulation reproducing the static Ic(Vce,Ib) transistor transfer data.