An analytical model for trapping-state photodepopulation measurements in conductor-thin-film-insulator-conductor structures is presented. The external-circuit-current dependence on applied voltage is determined, and it is shown that moments of the spatial distribution of trapped charge in the insulator can be extracted from collected-charge versus applied-field characteristic curves. The photodepopulation technique is compared with more widely used differential-capacitance and phtoemission-current techniques.

• Received 11 July 1973

DOI:https://doi.org/10.1103/PhysRevB.9.1874