MOLECULAR-BEAM EPITAXIAL-GROWTH OF GREEN LIGHT-EMITTING-DIODES ON ZNSE WAFERS

We have performed a preliminary investigation into the use of ZnSe bulk crystals fabricated by Sumitomo Electric Industries, Ltd. as substrates for the epitaxial deposition of ZnSe-based materials and light emitting devices. A low temperature (<380 degrees C) in-situ cleaning process has been developed for the (100) oriented ZnSe wafers involving the use of a remotely generated atomic hydrogen beam. The process produces a (1 x 1) atomically smooth ZnSe surface which is highly suitable for epitaxy. Hall-effect measurements performed on nitrogen-doped p-type ZnSe/S.I. ZnSe epilayers have revealed free-hole concentrations in the homoepitaxial material as high as 2.1 x 10(17) cm(-3), so far, with room temperature and 77K hole mobility values of 20 and 100 cm(2)V(-1)s(-1), respectively. Finally, green light emitting diodes have been grown on the ZnSe wafers having Cd0.2Zn0.8Se/ZnSe multiple quantum well active regions which have exhibited electroluminescence peak linewidths around 9.9 nn at room temperature.