OMVPE GROWTH OF THE NEW SEMICONDUCTOR ALLOYS GAP1-XSBX AND INP1-XSBX

The III/V semiconductor alloys GaP1-xSbx and InP1-xSbx have been grown for the first time with compositions covering the entire range from x=0 to 1.0. Despite the large miscibility gaps, which are calculated to extend nearly throughout the whole composition range at the growth temperatures of 530 to 600°C for GaPSb and 460 to 600°C for InPSb, epilayers with compositions well inside the miscibility gaps have been grown successfully by organometallic vapor phase epitaxy at atmospheric pressure using the reactants trimethylgallium, trimethylindium, trimethylantimony and phosphine. From a study of solid versus vapor composition for InPSb growth, the Sb distribution coefficient was determined to be nearly constant with the value between 12 and 15 at temperatures in the range 460-500°C. The 10 K energy band gap as a function of composition has been determined from photoluminescence measurements, X-ray diffraction and electron microprobe analysis.