Electroluminescence of type II broken-gap p-Ga0.84In0.16As0.22Sb0.78∕p-InAs heterostructures with a high-mobility electron channel at the interface

Abstract

Effects of lattice mismatch and bulk anisotropy on interband tunneling in broken-gap heterostructures J. Appl. Phys. 97, 063704 (2005); 10.1063/1.1857058 Interface photoluminescence in type II broken-gap P-Ga 0.84 In 0.16 As 0.22 Sb 0.78 / p-InAs single heterostructures Low temperature photoluminescence of Ga 0.84 In 0.16 As 0.22 Sb 0.78 solid solutions lattice matched to InAsGa 0.84 In 0.16 As 0.22 Sb 0.78 quaternary solid solutions, lattice matched to InAs, were grown by liquid phase epitaxy on ͑100͒-oriented p-InAs substrates from In-rich melt. The p-type Ga 0.84 In 0.16 As 0.22 Sb 0.78 layers were intentionally undoped or slightly doped with Sn to the hole concentration about p ϳ 5 ϫ 10 16 cm −3 . This allowed us to obtain a high-mobilityϳ͑3.5− 5.0͒ ϫ 10 4 cm 2 V −1 s −1 electron channel at the type II broken-gap p-Ga 0.84 In 0.16 As 0.22 Sb 0.78 / p-InAs heterointerface. Low-temperature ͑T =5 K͒ electroluminescence spectra exhibited two pronounced emission bands h 1 = 0.372 eV and h 2 = 0.400 eV under forward bias. The emission band h 2 was split into two lines and was attributed to interband transitions through acceptor and valence-band states in the bulk InAs, whereas emission band h 1 was ascribed to interface-related radiative transitions of electrons from the two-dimensional electron channel to the interface states at the p-Ga 0.84 In 0.16 As 0.22 Sb 0.78 / p-InAs heteroboundary.