由于与GaN晶格失配小(约1.4%),γ-LiAlO2单晶有望成为一种很有希望的CaN外延衬底材料.本文使用提拉法生长出了尺寸达φ45×50mm3的γ-LiAlO2单晶.对该晶体毛坯的各个有代表性的位置作了X射线粉末衍射(XRPD)分析,结果表明仅仅在晶体毛坯的底部生成了一种缺锂相(LiAl5O8).γ-LiAlO2晶体化学稳定性差,在室温时轻微水解.当在空气中于1100℃退火70h,γ-LiAlO2晶体挥发出锂组分,在表面产生缺锂相(LiAl5O8).值得注意的是,在γ-LiAlO2晶体的红外光谱区不存在氢氧根吸收带.
γ-LiAlO2 single crystals were anticipated to act as a promising substrate material for the epitaxy of GaN because of the little lattice misfit ( about 1.4% ) between each other. In the present work, largesize γ-LiAlO2 single crystal with dimension of φ45 × 50mm3 has been grown by Czochralski technique.Various representative positions of the crystal boule were examined using X-ray powder diffraction (XRPD) analysis. Only in the bottom of the crystal boule there produced a kind of lithium-poor phase (LiAl5 O8 ). The γ-LiAlO2 crystal exhibits a poor chemical stability because it hydrolyzes slightly at room temperature. When the γ-LiAlO2 crystal was annealed for 70h at 1100℃ in air-atmosphere, it volatilizes a lithium component, and produces a lithium-poor phase ( LiAl5 O8 ) layer on the surface. It is noteworthy that no hydroxyl absorption band presents in the infrared spectra region of γ-LiAlO2 crystals.
参考文献
| [1] | Shuji Nakamura;Masayuki Senoh;Shin-ichi Nagahama;Naruhito Iwasa, Takao Yamada, Toshio Matsushita, Yasunobu Sugimoto, Hiroyuki Kiyoku .Room-temperature Continuous-wave Operation of InGaN Multi-quantum-well-structure Laser Diodes with a Long Lifetime[J].Applied Physics Letters,1997,70:868. |
| [2] | Amano H;Sawaki N;Akasaki I;Toyoda Y .Metalorganic Vapor Phase Epitaxial Growth of a High Quality GaN Film Using an AlN Buffer Layer[J].Applied Physics Letters,1986,48:353. |
| [3] | Kakuya Iwata;Hajime Asahi;Kumiko Asami .Gas Source Molecular Beam Epitaxy Growth of GaN on C-, A-,R- and M-plane Sapphire and Silica Glass Substrates[J].Japanese Journal of Applied Physics,1997,6:L661. |
| [4] | Xu Ke;Xu Jun;Deng Peizhen;Zhou Yongzong, Zhou Guoqing, Qiu Rongsheng, Fang Zujie .γ-LiAlO2 Single Crystal: a Novel Substrate for GaN Epitaxy[J].Journal of Crystal Growth,1998,193:127. |
| [5] | WALTEREIT P;Brandt O;Trampert A;Grahn H T, Menniger J, Ramsteiner M, Reiche M, Ploog K H .Nitride Semiconductors Free of Electrostatic Fields for Efficient White Light-emitting Diodes[J].Nature,2000,406:865-868. |
| [6] | Waltereit P.;Ramsteiner M.;Trampert A.;Grahn HT.;Menniger J.;Reiche M.;Ploog KH.;Brandt O. .M-plane GaN(1(1)over-bar-00) grown on gamma-LiAlO2(100): nitride semiconductors free of internal electrostatic fields[J].Journal of Crystal Growth,2001(0):437-441. |
| [7] | Cockayne B;Lent B .The Czochralski Growth of Single Crystal Lithium Aluminate, LiAlO2[J].Journal of Crystal Growth,1981,54:546. |
| [8] | Zou Jun;Peng Guan-liang;Chen Junhua .Annealing Study of LiAlO2 Crystal Grown by Temperature Gradient Technique[J].人工晶体学报,2004,33:991. |
| [9] | 邹军,彭观良,陈俊华,李抒智,杨卫桥,周国清,徐军,周圣明.γ-LiAlO2晶体生长挥发和腐蚀研究[J].人工晶体学报,2004(06):987-990,981. |
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