PROPERTIES OF HG1-XCDXTE EPITAXIAL LAYERS PREPARED BY METALORGANIC CHEMICAL-VAPOR-DEPOSITION

Hg1-xCdxTe/CdTe/GaAs (x = 0.2-0.4) structures were grown from vapors o f dimethylcadmium, diethyltellurium, and mercury by the interdiffused multilayer process on GaAs (100) and (111)B substrates in a vertical r eactor under flowing hydrogen. The morphology, structural perfection, chemical homogeneity, and electrical properties of the structures were studied. A decrease in growth temperature from 400 to 350 degrees C r esults in better properties of Hg1-xCdxTe. At 77 K the best n-type sam ples showed a carrier concentration of (2-4) x 10(15) cm(-3), mobility of (5-13) x 10(4) cm(2)/(V s), and composition homogeneity Delta x = +/- 0.02 over the 25-mm-diameter substrate surface. The FWHM of rockin g curves was measured to be 4'-6' for (100)-oriented layers and 3'-5' for (111)B layers.