Negative charge state of hydrogen species in n-type GaAs

Publisher Website
Google Scholar
Abstract
Having been exposed to hydrogen plasma, the Te‐doped GaAs wafers were deposited with metal Ti, to form the Ti/n‐GaAs Schottky barrier diodes (SBDs). The profiles of donor concentration after successive annealing of the hydrogenated SBD at several reverse biases at 100 °C, indicated that the donor concentration in the strong electrical field region of the depletion layer increase monotonically and the donor concentration in the weak electrical field region of the depletion layer decrease monotonically with time. It is confirmed that hydrogen can be present as a negatively charged species in n‐type GaAs and thus one can conclude that besides the deep donor level determined previously, hydrogen in GaAs has an acceptor level in the lower half of the energy gap or near the mid gap. There is evidence that the stronger the electrical field in strong field region of depletion layer, the faster the TeH complexes decompose in that region during a reverse bias annealing.