METALORGANIC MOLECULAR-BEAM EPITAXIAL-GROWTH KINETICS AND DOPING STUDIES OF (001) ZNSE

Thermally pre-cracked diethylzinc and diethylselenide were used for th e metalorganic molecular beam epitaxial growth of (001) ZnSe films on (001) GaAs substrates. The growth kinetics of (001) ZnSe was studied b y measuring the growth rate as a function of the substrate temperature and the II/VI flux ratio. Arrhenius plot of the Se-limited growth rat e indicated an activation energy of 0.08 eV for the desorption of the Se species using Se and Se2 species for ZnSe growth. Triallylamine, al lylamine, tertiary-butylamine and ammonia were evaluated as sources fo r the N doping of ZnSe. Secondary ion mass spectrometry measurements w ere used to determine the impurity concentrations. When the amines wer e pre-cracked in the cracker cell, N concentrations in excess of 1 X 1 0(19) cm-3 were incorporated in films grown at less-than-or-equal-to 2 25-degrees-C. The N concentration decreased sharply with increased sub strate temperature. Large concentrations of C and H were measured in f ilms doped using the amines, and correlated with N concentrations; wit h ammonia, high H concentrations were observed and also correlated wit h the N concentration.