Abstract
A phenomenological model of electron-beam-induced contrast (EBIC) of dislocations perpendicular to the surface and of ‘point-like’ defects is developed. It takes into account the contributions of both the space-charge and bulk regions of a Schottky diode perpendicular to the electron beam. The radius ϵ of the cylinder by which the dislocation is represented increases with depth in the space-charge region (SCR) to its bulk value ϵ0. The influence of the parameters on which the EBIC contrast depends is detailed. It is shown that the reduced minority-carrier lifetime at the dislocation can be deduced from the shape of the EBIC curves c =f(E 0) (E o is the accelerating voltage of primary electrons). By comparing the theoretical value of the contrast with experiment, a value of about 50 nm is assigned to ϵ0. A characterization method for electrically active defects in CdTe is suggested.