Hydrogen-ion implantation in GaAs

The results of the basic study on depth distribution of hydrogen atoms and corresponding damage profiles produced by 50 keV H-ion implantation in (100 ) GaAs are reported. The influence of the H-ion dose and of the temperature of implantation and subsequent annealing were studied. The depth distribut ion of hydrogen was measured using the N-15(p,alpha gamma)C-12 nuclear reac tion, whereas the RBS/channeling was applied for defect analysis. Two tempe rature regions revealed: at temperatures below 90 degreesC independently of the hydrogen dose no blisters were found, whereas, at temperatures above 1 20 degreesC blisters appear at doses exceeding the critical value. In the l atter region hydrogen-defect complex formation was observed which are effec tive hydrogen traps and stabilize the radiation damage. With the increasing H-ion dose these complexes agglomerate into hydrogen gas bubbles. The incr ease of gas pressure in such bubbles upon subsequent thermal treatment can result in the splitting of a surface layer from the substrate. (C) 2001 Els evier Science Ltd. All rights reserved.