A THEORETICAL-STUDY OF THE CHARGE COLLECTION CONTRAST OF LOCALIZED SEMICONDUCTOR DEFECTS WITH ARBITRARY RECOMBINATION ACTIVITY

The charge collection contrast of a small spherical defect or a straight dislocation parallel to the surface of a semiconductor is calculated by a direct, though approximate, solution of the integral equation for the excess minority carrier density in the presence of each defect. The analysis is carried out for a semi-infinite semiconductor where the surface acts as a collector, and holds for arbitrary recombination activity of the defect. The new expressions for the effective strength are shown to extend earlier results obtained for the dislocation case with the iteration-perturbation method. The relation between measured defect strength and defect characteristics is illustrated and the range of validity of the first-order contrast analysis is discussed.