LOW-TEMPERATURE GROWTH AND NITROGEN DOPING OF ZNSE USING DIETHYLZINC AND DITERTIARYBUTYLSELENIDE IN A PLASMA-STIMULATED LOW-PRESSURE METALORGANIC VAPOR-PHASE EPITAXY SYSTEM

Ditertiarybutylselenide (DTBSe) and diethylzinc (DEZn) were used as pr ecursors for the growth of ZnSe in a low-pressure metalorganic vapour phase epitaxy (MOVPE) process. To reduce the growth temperature furthe r, we analysed both samples grown with and without plasma precracked D TBSe. ZnSe was doped with plasma activated nitrogen during the growth process. A planar doping scheme was developed to suppress the hydrogen and carbon incorporation into the layers. The diffusion controlled gr owth regime was observed down to 315 degrees C. Below 315 degrees C th e kinetically controlled growth regime was found by using DTBSe withou t plasma enhancement. For these samples the emissions of bound exciton s in 11 K PL spectra dominate, but in spectra of samples grown with pl asma below 360 degrees C deep center emissions appear. The homogeneous ly doped ZnSe layers contain carbon (4.0 x 10(16) cm(-3)) and hydrogen (1.8 x 10(18) cm(-3)) originating from the precursors. The separation of the doping and the growth process reduces the hydrogen incorporati on down to 4.5 x 10(17) cm(-3). The nitrogen concentration was 3 X 10( 16) cm(-3) for both methods.