III-N-V low-bandgap nitrides and their device applications

Abstract

Four families of III-N-V compounds for electronic and optoelectronicapplications are presented: InNAsP/InP, GaInNAs/GaAs, Ga(In)NP/GaP andGaInNP/GaAs. InNAsP/GaInAsP quantum wells grown on InP are superior forlong-wavelength microdisc lasers (and so expected for edge-emitting lasers),as compared to GaInAs/GaInAsP quantum wells, because of the larger conductionband offset from the addition of a small amount of nitrogen (0.5% to 1%) inthe InAsNP quantum wells. GaInNAs/GaAs heterostructures emitting at 1.3 µmat room temperature have stimulated much interest in 1.3 µmvertical-cavity surface-emitting lasers. Here we report the use of GaInNAs asthe base of a heterojunction bipolar transistor (HBT), which exhibits a lowerturn-on voltage than HBTs with the usual GaInAs base. Incorporating a smallamount of N in GaNxP1-x alloys leads to a direct bandgap behaviour ofGaNP, and red light-emitting diodes based on a GaNP/GaP double heterostructuregrown directly on (100) GaP substrates have been fabricated. Finally,incorporating N into GaInP barriers in a quantum well is shown to lower theconduction band offset, and GaInNP/GaAs could be potentially ideally suitedfor npn HBTs.