| 摘要 |
<p>The invention is intended for the metrology of semiconductor materials and provides means for the all-optical determination of the instantaneous photoconductivity type of a semiconductor crystal, if excess carriers are excited from deep levels. The method can be used for the characterization and subsequent improvement in fabrication of semiconductor materials designed for the applications in optoelectronic and electronic devices. The proposed method for the determination of the instantaneous photoconductivity type of semiconductor uses for optical pumping two coherent beams that induce a spatially modulated free carrier pattern in semiconductor, introduces an additional probe beam that diffracts on the dynamic grating, monitors the temporal kinetics of the diffraction efficiency at various excitation levels and dynamic grating periods, determines the effective diffusion coefficient as a function of excitation, and from the character of the latter dependence determines the photoconductivity type of s</p> |
