Ion implantation of Boron in GaAs MESFET's

The quality of the GaAs substrate plays a major role in MESFET performance for devices fabricated by direct ion implantation of silicon atoms into liquid-encapsulated Czochralski (LEC) material. High-energy (270-keV)
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B+ implantation was used to improve the silicon impurity distribution near the substrate interface, reduce substrate effects, and produce a more abrupt interface. Since current conduction under low-noise MESFET operation occurs in this region of the channel, microwave performance is improved significantly.