Separation of bulk lifetime and surface recombination velocity by multi-wavelength technique

In this paper a contactless, all-optical and non-destructive technique for simultaneous measurement of minority carrier recombination lifetime and surface recombination velocity, is presented. The principle is based upon measurement at low injection level, of the free carrier optical absorption transient probed by an infrared beam following electron-hole pair excitation by a pulsed laser beam working at several wavelengths. Being contactless and non-destructive with respect to the, surface to be analyzed, the method is appealing for routine lifetime characterization.