Arsenic-related recombination in MOVPE-grown ZnO/GaAs films

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• 作者：J.R. Botha ; K.T. Roro ; C. Weichsel ; A.W.R. Leitch ; J. Weber
• 关键词：ZnO ; MOVPE ; GaAs substrate ; Acceptors
• 刊名：Superlattices and Microstructures
• 出版年：2007
• 出版时间：July-December 2007
• 年：2007
• 卷：42
• 期：1-6
• 页码：26-32
• 全文大小：462 K

文摘

In this paper, ZnO films grown by metalorganic vapour phase epitaxy on various substrates (GaAs, silicon, sapphire) and using different VI /II ratios, are investigated by photoluminescence (PL) spectroscopy. The PL spectra of layers grown on GaAs show significant recombination at 3.320 eV, 3.305 eV and 3.270 eV. These energies are remarkably similar to what have been reported for hybrid beam deposited ZnO:As [Y.R. Ryu, T.S. Lee, H.W. White, Appl. Phys. Lett. 83 (2003) 87] and arsenic-implanted ZnO crystals [T.S. Jeong, M.S. Han, C.J. Youn, Y.S. Park, J. Appl. Phys. 96 (2004) 175], and the lines are ascribed to the incorporation of arsenic, which diffuses from the substrate into the films. Two acceptor levels are deduced at 120 meV and at 140–150 meV.