MeV implantation of gallium arsenide

The authors investigated n-type MeV implants into semi-insulating GaAs to fabricate fully implanted varactor diodes for monolithic millimeter-wave applications. Single and multiple implants of Si from 6 to 2.5 MeV and 6 MeV S implants in GaAs were studied before and after capless furnace annealing and rapid thermal annealing by chemical profiling using secondary ion mass spectrometry (SIMS) and electrochemical and traditional differential capacitance-voltage profiling. A buried active layer at a depth of 2.8 μm with a peak carrier concentration of 2.5 x 1018 cm-3 was achieved by using 6 MeV Si + 4 MeV Si + 6 MeV S implants and rapid thermal annealing them at a temperature 1050 degree C for 10 seconds. The chemical profiles are correlated to the electrical profiles to determine activation and annealing behavior of MeV Si and S implants in semi-insulating GaAs. 5 refs., 7 figs. 1 tab