OPTICAL STUDIES OF VERY HIGH-PURITY GAAS GROWN BY METAL-ORGANIC CHEMICAL-VAPOR-DEPOSITION USING A POINT-OF-USE ARSINE (ASH3) GENERATOR

We describe low-temperature photoluminescence studies of high-purity e pitaxial GaAs and GaAs/AlGaAs quantum wells;grown in a low-pressure me tal-organic chemical-vapor deposition (MOCVD) reactor using electrolyt ically generated AsH3 as the group V source material and trimethylgall ium and trimethylaluminum as the group III sources. The use of on-site point-of-use generated AsH3, made using the electrolytic conversion o f solid As source material, greatly improves the safety of the MOCVD g rowth process, since AsH3 is generated only as needed, and at any time only a small volume of AsH3 is present. The photoluminescence studies indicate that very high-purify GaAs and GaAs/AlGaAs quantum wells lay ers are obtained using this source of AsH3. The GaAs/AlGaAs material h as been used for a variety of devices including photodetectors and low threshold vertical cavity surface emitting lasers. (C) 1997 American Institute of Physics.