Abstract
The intensity of photoluminescence (PL) changes when an additional below‐gap excitation (BGE) light modifies the electronic occupation of one of the crystalline defects acting as nonradiative recombination (NRR) levels and shifts the balance between radiative and NRR rates. The photon energy of above‐gap excitation (AGE) light selects the layer and determines the depth of inspection, whereas that of BGE corresponds to the energy distribution of the NRR levels. The essential advantage of two‐wavelength excited PL (TWEPL) lies on a systematic combination of BGE spectroscopy and AGE spectroscopy for a variety of materials. It provides the noncontacting and nondestructive detection of NRR levels, distributing in a whole wafer as well as in a microscopic volume. Density and the electron and hole capture rates of NRR level 1, Nt1, Cn1, and Cp1, and those of level 2, Nt2 and Cp2, are determined consistently by the TWEPL measurement with the aid of time‐resolved PL. A brief review is given on the principle of the TWEPL, basic model of analysis, and experimental results of detecting NRR levels in GaAs/AlGaAs, InGaAs/GaAs, InAs/GaAs, GaN, InGaN, AlGaN, and GaPN. The method gives us a guiding compass toward the efficiency improvement of electronic devices from which PL is observable.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
