In this study,the thermal conductivity of 4H-SiC wafers was investigated from Low temperature(80 K)to room temperature(290 K)using laser Raman spectroscopy with laser excitation.Throughout the measurement process,the laser acts as both an excitation and a heat source for the Raman spectra,raising the local temperature of the wafer surface by laser heating.The thermal conductivity of the 4H-SiC wafer was obtained by analyzing the relationship between the shift in Raman spectral position and the increase in local temperature.The results show that the thermal conductivity of 4H-SiC wafers increases with increasing temperature at low temperatures,when K∝T3,and decreases with increasing temperature when the thermal conductivity reaches its maximum value,when K∝T-1,which is attributed to phonon-phonon interactions and phonon defect scattering.
关键词
4H-SiC/热导率/拉曼光谱/低温
Key words
4H-SiC/thermal conductivity/raman spectroscopy/low temperature
维普
万方数据