ABSTRACT
Atomic hydrogen is shown to be unintentionally incorporated into GaAs, AlGaAs and InP during gas-source (MOMBE, MOCVD) growth and subsequent processing steps. For example, hydrogen injection into p-type GaAs during boiling in water or etching in H2SO4:H2O2:H2O has been detected by the resultant acceptor passivation and more directly by SIMS after processing with deuterated chemicals. Dry etching of these materials in C2H6/H2 or CH3 Cl plasmas leads to substantial dopant passivation, and this can occur even when hydrogen is not a specific part of the plasma chemistry because of the presence of water vapor, photoresist mask erosion and so on. Hydrogen also readily permeates into III-V materials during annealing at moderate temperatures (~500°C) in H2-containing ambients.
