Room temperature InPSb/InAs and InPSb/InAs/InAsSb mid-infrared emitting diodes grown by MOVPE

Abstract

Strained InAsSb heterostructures are important materials for a variety of new III-V based mid-infrared emitters. In the study InP/sub 0.69/-Sb/sub 0.31/-InAs light-emitting diodes (LEDs) employing an InAs-InAs/sub 0.94/Sb/sub 0.06/ multiquantum-well (MQW) active region have been investigated. They were characterised using electro-optical techniques and X-ray diffractometry. The authors have measured the temperature dependence of electroluminescence (EL): at low temperatures, the EL-intensity of the MQW diodes is higher than that of a simple PIN InPSb-InAs-InPSb structure. For both devices, room temperature EL could be resolved (emission wavelength of 3.3 /spl mu/m, FWHM of 70 meV) which is related to InAs near-bandgap transitions. InAsP/InAsSb MQWs were grown to achieve higher antimony contents in the wells. The heterostructures were strain-balanced and enabled an antimony incorporation of 24% with, at the same time, high structural quality. In the photoluminescence (PL) spectra of InAs/sub 0.95/P/sub 0.05/-InAs/sub 0.86/Sb/sub 0.14/ MQWs strong features were observed around 4.2 /spl mu/m due to atmospheric CO/sub 2/ absorption.