LOCK-IN-PHASE ANALYSIS OF n-GaAs PHOTOREFLECTANCE SPECTRA

Abstract

The modulation spectroscopy Photoreflectance (PR) is a contact_free, nondestructive, sensitive, optical experimental method for examining the surface and interface properties of semiconductors. Many experimental results indicate a phase delay of the photoreflectance signal relative to the optical Modulation (1:4). The Phase dependence of the PR-signal has been investigated by using the two-channel lock-in techniqe. The linear form of the phase diagram is a confirmation of the single -component character of the PR-signal. As the first step, we simulate the structure in the phase diagram of two components spectrum. When we change the range of photon energy values, the structures in phase diagram don't change so much.