中国物理B ›› 2011, Vol. 20 ›› Issue (3): 33301-033301.doi: 10.1088/1674-1056/20/3/033301
李锡光1, 王占国2, 曾一平3, 孙国胜4, 刘兴昉5, 吴海雷5, 闫果果5, 董林5, 郑柳5, 赵万顺5, 王雷5
Sun Guo-Sheng(孙国胜)a)b)c), Liu Xing-Fang(刘兴昉)b), Wu Hai-Lei(吴海雷)b), Yan Guo-Guo(闫果果)b), Dong Lin(董林)b), Zheng Liu(郑柳)b), Zhao Wan-Shun(赵万顺)b), Wang Lei(王雷) b), Zeng Yi-Ping(曾一平)a)b), Li Xi-Guang(李锡光)c), and Wang Zhan-Guo(王占国) a)
摘要: The free carrier density and mobility in n-type 4H-SiC substrates and epilayers were determined by accurately analysing the frequency shift and the full-shape of the longitudinal optic phonon--plasmon coupled (LOPC) modes, and compared with those determined by Hall-effect measurement and that provided by the vendors. The transport properties of thick and thin 4H-SiC epilayers grown in both vertical and horizontal reactors were also studied. The free carrier density ranges between 2×1018 cm-3 and 8×1018 cm-3 with a carrier mobility of 30--55 cm2/(V·s) for n-type 4H-SiC substrates and 1×1016--3×1016 cm-3 with mobility of 290--490 cm2/(V·s) for both thick and thin 4H-SiC epilayers grown in a horizontal reactor, while thick 4H-SiC epilayers grown in vertical reactor have a slightly higher carrier concentration of around 8.1×1016 cm-3 with mobility of 380 cm2/(V·s). It was shown that Raman spectroscopy is a potential technique for determining the transport properties of 4H-SiC wafers with the advantage of being able to probe very small volumes and also being non-destructive. This is especially useful for future mass production of 4H-SiC epi-wafers.
中图分类号: (Raman and Rayleigh spectra (including optical scattering) ?)