MEV ION-IMPLANTATION IN GAAS TECHNOLOGY

The technology base of MeV ion implantation in GaAs is reviewed. n-type implantation using Si and Si and S co-implants is emphasized. Experimental range and shape parameters obtained using secondary ion mass spectroscopy (SIMS) of Si implants having energies from 1 to 20 MeV are presented. Activation studies of these implants, as well as Si and S co-implants, annealed using both furnace anneal and rapid thermal anneal have been performed with Hall and capacitance-voltage measurements. Buried n+ profiles with a peak carrier concentration of 2 x 10(18)/cm3, located as deep as 6-mu-m beneath the surface have been formed with the co-implantation of Si and S. Application of these implants to GaAs device fabrication is discussed. Several techniques for masking the high energy implants during selective implantation are presented. The performance values of two demonstration devices, a mixer diode and a varactor diode, show that state-of-the-art devices can be fabricated using MeV implantation.