Micro-Raman Measurements and Depth Profiling of SiC Article
American Physical Society
Recent progress in growth of high quality 4H- SiC and 6H-SiC polytypes materials may lead to new applications for SiC as high power, high temperature, and high frequency devices that can tolerate harsh environments. Nondestructive techniques that could be used in analyzing various layers of such materials after growth or after exposure to harsh environment could be used in investigation of induced defects or structural damages. We have utilized micro-Raman scattering to investigate the depth profiling of Nitrogen doped 4H-SiC samples. Heavily N-doped 4H-SiC epilayers grown on low doped 4H-SiC substrates were examined. Each SiC sample was placed on micro-positioning translational stage in order to accurately control the focal plane of the laser beam within the sample by adjusting normal distance of the microscope objective with respect to the SiC wafer. We were able to clearly distinguish the epilayer from the SiC substrate. Strong phonon peaks and distinct coupled plasmon-LO phonon modes from the N-doped epilayer were used in this depth profiling analysis. A scattering efficiency model describing the optimal focusing condition for backscattering from a translucent sample was developed. The experimental results of depth profiling and our model for optimal backscattering condition will be presented and discussed.
Annual APS March Meeting 2003
© American Physical Society
Ramabadran, Uma and Roughani, Bahram, "Micro-Raman Measurements and Depth Profiling of SiC Article" (2003). Physics Publications. 47.