Growth of p-n Impurity-DopedZ-nTe Films, ZnSe Films and Superlattices by Hot Wall Epitaxy and Its Characterization.
March, 1994
Shingo Sakakibara
Irnpurity-doped ZriTefilms, ZnSe films, Zrite-7nSe superlattices (SL's), ZnSe-ZnS SL's and the light-emitting diodes (LED's), have been prepared on GaAs (Iffi) substrates by hot wall epitaxy (HWE) . For p-typeZdIe films, the existence of oxygen (O) for the LirP-doped Zr{Ie films was ascertained in the doped layen by secondary ion mass spectroscopy (SIMS) and then the Lif-doped TnTefilms with almost no oxygen could be prepared by appending the Hz 96. The N-dop edZritefilms with hole concentrations above 1gl? .rn-3 which showed excitonic photolurninescence @L) emission have been obtained for the first time. The activation energy of nitrogen acceptor was caluculated to be 5 I meV and 4O meV from the PL and the electrical propertyn respectively. N-doped 7-rffe-7nSe SL's with hole concentration of 2.3 x 1018 cm-3 which showed PL emission of interband transitiono were obtained for the first time and their hole concentration value was the highest ever reported. The hole concentration for the N-doped ZnSe films was 2.4
x 101? cm-3 and their crystalline quality was nearly equal to that grolyn by MBE. The electron concentration for the Cl-doped ZnSe films could be controlled from 8.4 x l0la cm-3 to 2.8 x 101e cm-3 by theZnClztemperature. .Moreover chlorine-doped (Cl-doped) ZnSe-ZnS SL's which showed n-qrpe conductivity and had high electron concentmions of 7.1 x 1017 cm-3, were obtained by HWE for the first time. Finally the LED's based on ZnSe p-n junctions which had good rectifying current-voltage chracteristics with the forward voltage (Vr) of about 3 V and electroluminescence emisson of blue-green region at77K, were fabricated.
-241-
