ELABORATION AND CHARACTERIZATION OF INASSB GROWN ON GASB AND GAAS SUBSTRATES

We study the growth of InAs0.91Sb0.09 lattice matched on GaSb presenti ng a bandgap of 0.29 eV (4.2 mu m) at 300 K. The layers are grown on ( 100) GaSb and GaAs substrates at atmospheric pressure in a vertical re actor MOVPE (metal organic vapor phase epitaxy) system using trimethyl indium (TMIn), trimethylantimony (TMSb) and arsine (AsH3). We report t he results on growth rate and InSb incorporation versus growth paramet ers as temperature and TMSb partial pressure for different V/III ratio s. Carrier density and mobility of InAsSb undoped layers are given. Op tical photoconductivity measurements are presented with a wavelength c ut off up to 5.4 mu m at 300 K, and the absorption by atmospheric CO2 at 4.25 mu m is clearly detected. The I-V curves of (n)InAsSb/(n and p )GaSb heterojunctions are presented. At room temperature, the dark cur rent for the n/n heterostructure is 70 mu A at -1 V, while the n/p jun ction is ohmic.