Plasma-surface interactions in the processing of III-V semiconductor materials

Surface modifications of InP and GaAs semiconductors induced by the interaction with H-2, N-2 and O-2 plasmas are investigated in situ and in real time by ellipsometry. It will be shown that: (a) the kinetic ellipsometry allows to define the "border line" between the cleaning (oxide removal) and damage (phosphorus depletion) processes of InP which can occurr during exposure to H atoms; (b) electronic phenomena at the GaAs/oxide interface play an important role in the oxidation kinetics; (c) the self-limiting kinetics of GaAs nitridation is due to the slow out-diffusion of As.