Significant progress has been made in the OMVPE growth of GaAs directly on Si by the previously reported low-temperature growth technique. These films have been characterized by low-temperature PL, SIMS, TEM, and DLTS. The epitaxial layers, whose quality has been determined by PL measurements (4.2 K PL spectral width of heavy-hole exciton ≈ 3 meV), were implanted with 29Si+ for fabrication of MESFET channels. Background concentrations of ≈ 1014 cm−3 have been achieved for the first time after rapid thermal annealing without the need to use oxygen implantation or vanadium doping. SIMS measurements do not show Si pileup on the surface or much Si diffusion at the GaAs-Si interface, a significant improvement over earlier results. DLTS measurements and electrical characterization of the GaAs-Si heterojunction diode indicate the presence of only two trap levels (< 1014 cm−3 in concentration) in the GaAs ≥ 2.5 μm away from the interface.

3. By ion implantation, the reflectivity of the wafer in the infrared region increases, but it decreases to a level below that of the substrate as the impurities are activated by annealing. Therefore the absorption of infrared rays increases and the heating rate becomes faster than that after ion implantation.4. Previously, the difference of the heating rate due to impurity concentration was reported, but now a similar effect is found in ion-implanted layers. ABSTRACTA new approach for capless rapid thermal annealing of ion implanted III-V semiconductors, the enhanced overpressure proximity (EOP) technique, has been developed and applied to GaAs implanted with Si +. The EOP method relies on the use of an Sn-coated GaAs wafer to provide a greater localized arsenic overpressure than can be achieved by the conventional proximity method which utilizes a GaAs wafer. Implant doses of 7 • 10 '~ and 1 • 10 '4 cm 2 havebeen investigated, yielding activations as high as 60 and 35%, respectively. Under the appropriate annealing conditions photoluminescence data confirm that EOP-RTA reduces the concentration of Si on As sites when compared with the conventional proximity approach. In addition, this technique permits an increased latitude in annealing times and temperatures that can be used without degradation of the wafer surface. The EOP approach can be easily extended for capless rapid thermal annealing of other implanted dopants in GaAs as well as other III-V compounds such as InP and InGaAs.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 138.251.14.35 Downloaded on 2015-06-07 to IP Vol. 134,No. 8