SUBSTRATE-QUALITY, SINGLE-CRYSTAL ZNSE FOR HOMOEPITAXY USING SEEDED PHYSICAL VAPOR TRANSPORT

We describe the results of optical and electrical characterization of seeded physical vapor transport (SPVT) ZnSe suitable for use as substr ates in homoepitaxy. Photoluminescence, Hall measurements, C-V data an d thermally simulated conductivity and luminescence (TSC/TL) results a re described. As-grown SPVT wafers are of very high crystallinity and of high resistivity. N-type conductivity can be induced by post-growth Zn-extraction, producing wafers with room temperature resistivities a s low as 3.82 OMEGA cm and free carrier densities of approximately 1.5 x 10(15) cm-3. The conductivity is limited by the presence of unwante d acceptors due to Cu and Li impurities. Deep level analysis reveals v arious electron and hole states within the as-grown specimens. Trap de pths and capture cross-sections are evaluated for the major centers.