Formation of thermally stable high resistance regions in doped AlGaAs by oxygen ion implantation.

Oxygen implantation into n sup + AlGaAs, followed by annealing above 600C creates a deep acceptor level which compensates the shallow donors present in the material. Temperature dependent Hall measurements show the resistivity of this compensated AlGaAs has a thermal activation energy of 0.49 eV, in contrast to a value of 0.79 eV for compensation caused by ion-induced damage. However the latter is stable only to 600C whereas the chemically induced compensation in O-implanted AlGaAs is stable above 950C. We detail the evolution of the resistivity of both types of material as a function of post-implant annealing temperature. The use of this procedure for isolating SARGIC- SDHT devices is discussed.