ATMOSPHERIC PRESSURE METAL-ORGANIC CHEMICAL VAPOUR DEPOSITION (APMOCVD) FOR THE GROWTH OF ZnSe EPILAYERS ON (100)-GaAs SUBSTRATES USING DIETHYL-ZINC (DEZn) AND HYDROGEN SELENIDE (H2Se)

ZnSe has been grown by atmospheric pressure metal-organic chemical vapour deposition (APMOCVD) using DEZn and H2Se (5% in H2). The preparation and purification of DEZn is briefly described. Epitaxial layers, ca 1-8.5 µm in thickness, grown on (100)-GaAs substrates at different temperatures (TG), different VI/II ratios and growth rates (GR) have been characterised in terms of X-ray structure, electrical (Hall) and optical properties. With high purity DEZn, undoped ZnSe with electron concentration ca 1x1015 cm-3 with mobilities of ca 4500 cm2V-1s-1 at 77 K and a VI/II ratio of ca 15 is obtained. For this material, low temperature PL emission lines Iv (2.7777 eV) and Yo (2.6050 eV) are observed with variable intensities and these are assigned to transitions involving a variety of Se-defect sites in contrast to the majority of recent literature assignments