CVD growth of SiC on sapphire substrate and graphene formation from the epitaxial SiC

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• 作者：Jeonghyun Hwang ; ¹ ; ^{jh124@cornell.edu} ; Moonkyung Kim¹ ; Virgil B. Shields ; Michael G. Spencer
• 关键词：A1. X-ray diffraction ; A1. Raman spectroscopy ; A3. Chemical vapor deposition processes ; B1. Carbides ; B1. Graphene ; B1. Nitrides
• 刊名：Journal of Crystal Growth
• 出版年：2013
• 出版时间：1 March, 2013
• 年：2013
• 卷：366
• 期：Complete
• 页码：26-30
• 全文大小：806 K

文摘

6H-SiC epi-layer was grown on c-plane sapphire by chemical vapor deposition (CVD) and epitaxial graphene was grown on the SiC film using the thermal decomposition method. A thin (¡«300 nm) AlN was employed as a buffer layer since a direct growth on sapphire did not produce SiC. Raman spectroscopy, x-ray diffraction (XRD), and atomic force microscopy (AFM) confirmed the growth of high quality 6H-SiC on the AlN/sapphire at 1450 ¡ãC. The effect of AlN growth method/condition (HVPE and MBE) on the quality of final SiC film and epitaxial graphene was explored. Raman and XRD 2¦È-scan did not show any significant difference between the SiC films grown on HVPE-AlN and MBE-AlN. A sharper XRD rocking curve was observed on the SiC/HVPE-AlN but a smoother SiC was grown on the MBE-AlN. Graphitization of the SiC/AlN/sapphire was done at 1300-1400 ¡ãC under Ultra High Vacuum (UHV). The SiC on MBE-AlN survived at high temperatures (up to 1400 ¡ãC) without cracking and graphene was grown on it. However, the SiC on HVPE-AlN cracked and peeled off at 1300 ¡ãC resulting in no formation of graphene. The signatures of graphene were clearly observed by Raman spectroscopy with the 2D-peak to G-peak intensity (I_2D/I_G) of approximately 2, the D-peak to G-peak intensity (I_D/I_G) of 0.4, and the 2D-peak width of 55 cm^?1.