THE INFLUENCE OF THERMAL PREANNEALS ON THE HYDROGEN PASSIVATION EFFICIENCY IN LIQUID ENCAPSULATED CZOCHRALSKI-GROWN GAAS

The introduction rate of a hydrogen-related bistable electron trap, formed by a 150°C plasma annealing, depends strongly on thermal preannealing. A pure thermal 850°C preanneal completely anneals the native defects EL6 and EL3, reduces the native defect concentration EL2 by a factor of 10, and decreases equally the introduction rate of the bistable defect by a factor of 10. From a comparison between the profiles of these defects, it is possible to get informations on the microscopic structure of this hydrogen related defect as well as on the EL2 defect.