Independence verification and decoupling measurement of Raman shift coefficients with coexisting temperature and stress

The foundation of Raman decoupling measurement for temperature and stress is the independence of the two Raman shift coefficients when the two physical fields coexist, which remains unverified. Examining the thermoelastic model of a double-layer structure via phonon frequency shift theories, provides an accurate and convenient method to verify independence, while simultaneous decoupling determines the Raman shift temperature and stress coefficients. Wurtzite GaN was used to evaluate this method, as the independence of the influences of temperature and stress on the E 2 (high) frequency of wurtzite GaN can be verified by the linearity of the data. The E 2 (high) shift coefficients of temperature and stress were determined as -0.01418 +/- 0.0 0 02 cm -1 /K and -3.06 +/- 0.28 cm -1 /GPa, respectively, which are in good agreement with the literature, further confirming the measurement reliability. (c) 2021 Published by Elsevier Ltd.

Automated summary

This paper investigates the foundation of Raman decoupling measurement for temperature and stress. By examining the thermoelastic model and phonon frequency shift theories, the independence of temperature and stress effects on Wurtzite GaN is verified, and the corresponding Raman shift coefficients are determined, which are consistent with the literature and confirm the measurement reliability.