OPTICAL AND ELECTRICAL-PROPERTIES OF INALAS ALASSB TYPE-II QUANTUM-WELL STRUCTURES GROWN BY MOLECULAR-BEAM EPITAXY/

In0.52Al0.48As/AlAs0.56Sb0.44 type II multiple quantum well (MQW) laye rs lattice-matched to InP substrates were grown by molecular beam epit axy (MBE). Light emission at 0.91-0.97 mu m was observed at 77 K, whic h arises from the recombination between electrons in the InAlAs layers and holes in the AlAsSb layers across the type IT heterointerface. Th e conduction band discontinuity Delta E-c at Gamma point is estimated to be 1.25 eV from the InAlAs well-width dependence of the emission en ergy. In addition, an InAlAs/AlAsSb double barrier resonant tunneling diode was fabricated, which shows a clear negative differential resist ance at 77 K. (C) 1998 Elsevier Science B.V. All rights reserved.