New field-effect transistor with quantum wire and modulation-doped heterostructures

Abstract
A new field-effect transistor, consisting of an AlGaAs/GaAs heterostructure and an (AlAs)0.25(GaAs)0.75 vertical superlattice, is fabricated. It has a large transconductance of 14mS/mm at a gate length of 250 μm, corresponding to a transconductance of 3.5S/mm for 1μm gate length. Hall measurement revealed a novel FET operation mode called ‘velocity modulation’.