Overcoming diffusion-related limitations in semiconductor defect imaging with phonon-plasmon-coupled mode Raman scattering
- Univ. of North Carolina, Charlotte, NC (United States); Wuhan Univ. of Technology (China)
- Univ. of North Carolina, Charlotte, NC (United States)
- Davidson College, Davidson, NC (United States)
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
Carrier diffusion is of paramount importance in many semiconductor devices, such as solar cells, photodetectors, and power electronics. Structural defects prevent such devices from reaching their full performance potential. Although a large carrier diffusion length indicates high material quality, it also implies increased carrier depletion by an individual extended defect (for instance, a dislocation) and obscures the spatial resolution of neighboring defects using optical techniques. For commonly utilized photoluminescence (PL) imaging, the spatial resolution is dictated by the diffusion length rather than by the laser spot size, no matter the spot is at or below the diffraction limit. We show how Raman imaging of the LO phonon-plasmon-coupled mode can be used to recover the intrinsic spatial resolution of the optical system, and we demonstrate the effectiveness of the technique by imaging defects in GaAs with diffraction-limited optics, achieving a 10-fold improvement in resolution. Furthermore, by combining Raman and PL imaging, we can independently and simultaneously determine the spatial dependence of the electron density, hole density, radiative recombination rate, and non-radiative recombination rate near a dislocation-like defect, which has not been possible using other techniques.
- Research Organization:
- National Renewable Energy Laboratory (NREL), Golden, CO (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE); US Army Research Office (ARO); National Natural Science Foundation of China (NSFC); China Scholarship Council (CSC)
- Grant/Contract Number:
- AC36-08GO28308; W911NF-10-1-0524; W911NF-16-1-0263; 51702245
- OSTI ID:
- 1461373
- Report Number(s):
- NREL/JA-5K00-71975
- Journal Information:
- Light, Science & Applications, Vol. 7, Issue 1; ISSN 2047-7538
- Publisher:
- Nature Publishing GroupCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Broadband transmission Raman measurements using a field-widened spatial heterodyne Raman spectrometer with mosaic grating structure
|
journal | January 2018 |
Broadband, high-resolution Raman observations from a double-echelle spatial heterodyne Raman spectrometer
|
journal | January 2018 |
Ring defects in n-type Czochralski-grown silicon: A high spatial resolution study using Fourier-transform infrared spectroscopy, micro-photoluminescence, and micro-Raman
|
journal | December 2018 |
Similar Records
An all optical approach for comprehensive in-operando analysis of radiative and nonradiative recombination processes in GaAs double heterostructures
Comparative studies of optoelectrical properties of prominent PV materials: Halide perovskite, CdTe, and GaAs