InAs channel heterostructure-field effect transistors with InAs/AISb short-period superlattice barriers

We report on the implementation of InAs-channel heterostructure-field-effect transistors (HFETs) fabricated with InAs/AlSb short-period superlattice barriers. The InAs/AlSb superlattice barrier structure is advantageous for InAs/AlSb HFETs because of its improved chemical stability against oxidation when compared to pure AlSb, and its compatibility with silicon as an n-type dopant during growth by molecular beam epitaxy. The structures examined here consist of a 200-Angstrom-wide InAs quantum well inserted between 25/25 Angstrom InAs/AlSb superlattice barriers that provide a 0.5 eV conduction band discontinuity between the quantum well and the superlattice barrier. Fabricated HFET devices display complete channel modulation, confirming the field-effect operation at room temperature. In addition, we demonstrate the modulation doping of an InAs quantum well clad by silicon-doped InAs/AlSb superlattice barriers. (C) 1996 American Institute of Physics.