Impact of growth temperature on InAs/GaInSb strained layer superlattices for very long wavelength infrared detection

Abstract

We explore the optimum growth space for a 47.0 Å InAs/21.5 Å Ga0.75In0.25Sb superlattices (SLs) designed for the maximum Auger suppression for a very long wavelength infrared gap. Our growth process produces a consistent gap of 50 ± 5 meV. However, SL quality is sensitive to the growth temperature (Tg). For the SLs grown at 390−470 °C, a photoresponse signal gradually increases as Tg increases from 400 to 440 °C. Outside this temperature window, the SL quality deteriorates very rapidly. All SLs were n-type with mobility of ∼10 000 V/cm2 and 300 K recombination lifetime of ∼70 ns for an optimized SL.