Differentiated electron-beam-induced current (DEBIC): Quantitative characterization of semiconductor heterostructure lasers

Differentiated electron-beam-induced current (DEBIC) is shown to be well suited for the study of semiconductor heterostructure lasers. The DEBIC signal, unlike the standard EBIC signal, is rich in fine-structure information in the vicinity of the active region. A simple model is introduced to explain the characteristic DEBIC signal. As a result of the anisotropy of the carrier distribution, higher spatial resolution (≲0.2 μm) is achieved with DEBIC than with the standard technique, EBIC (?1 μm). The DEBIC can be used to obtain diffusion lengths of the minority carriers and to evaluate the quality and uniformity of the device fabrication.