Non-destructive deep trap diagnostics of epitaxial structures

摘要

A simple non-destructive method for determining the concentration of vacant deep traps in the vicinity of the film-substrate interface under extrinsic illumination is proposed and tested. The proposed technique relies on capacitance-voltage measurements under illumination. An increase in the width of the conductive channel under extrinsic illumination is expressed in terms of the structural parameters and the illumination-induced shift of the inflection point in the capacitance-voltage curve. The experimental results for GaAs epitaxial films are in satisfactory agreement with those obtained by an independent method based on sidegating measurements.