气相外延ZnSe单晶薄膜的蓝色电致发光

本文在300℃—700℃温度范围内,在GaAs衬底上气相外延生长了ZnSe单晶薄膜。讨论了衬底温度对外延层电学性质及光学特性的影响。ZnSe外延层经Zn气氛热处理后,发光特性大为改善。用处理后的ZnSe外延膜做成MIS发光二极管,首次得到了室温下气相外延ZnSe单晶薄膜的蓝色电致发光。

BLUE EIECTROLUMINESCENCE OF VAPOR PHASE EPITAXIAL ZnSe THIN FILMS

There has been considerable interest in blue electroluminescence (EL) in ZnSe diodes recently1-3]. In our earlier work,the attention was directed to the determination of the origin of the blue emission spectrum at room tem-peratature4,5] and the improvement of the spatial distribution of blue EL in ZnSe MIS diodes6].The study of the blue EL in ZnSe focused on bulk crystals by sublimation and other methods at high temperature.The as-grown ZnSe crystals usually contained a large number of intrinsic defects, and had high resistivity even if donor impurities had been dopped.So far,many papers reported on thin epitaxial films of ZnSe grown by MOCVD7,8],MBE9,10],LPE11,12] and VPE13-16],and high quality ZnSe epilayers were grown.However there were a few reports17,18] on preparing blue EL in ZnSe MIS diodes using the ZnSe epilayers. In the present paper we first reported the blue EL at room temperature from the vapor phase epitaxial ZnSe grown on GaAs.