ANNEALING OF SE-IMPLANTED GAAS ENCAPSULATED WITH AS-DOPED A-SI-H()

The surface of 100 keV Se+-implanted GaAs was encapsulated with As-dop ed a-Si:H with a thickness of about 80 nm. The sheet carrier concentra tion in thermally annealed samples increased with an increase in the c oncentration of As atoms in the a-Si:H encapsulant. A high sheet carri er concentration of 0.65 x 10(14) cm-2 can be achieved on GaAs which w as implanted with a dose of 3.3 x 10(14) cm-2 and annealed at 1000-deg rees-C for 15 min after encapsulation with an As-doped a-Si:H film. Fu rthermore, the diffusion rate of the implanted Se atoms was reduced wi th an increase in the concentration of As atoms in the encapsulant.