氨化Si基Ga_2O_3/Ta薄膜制备一维GaN纳米结构研究
|
摘要
GaN是一种十分优异的宽带隙Ш一V族化合物半导体材料,是当前世界上最先进的半导体材料之一。室温下,GaN的禁带宽度为3.4eV,是制作光电子器件,尤其是蓝、绿发光二极管(LEDs)和激光二极管(LDs)的理想材料。这类光源在高密度光信息存储、高速激光打印、全色动态高亮度光显示、固体照明光源、高亮度信号探测、通讯等方面有着广阔的应用前景和巨大的市场潜力。此外,GaN也是制作高温、高频、大功率器件的理想材料。进入90年代之后,随着材料生长和器件工艺水平的不断发展和完善,一些突破性技术的实现使GaN材料的研究空前活跃,GaN己经成为世界各国争相研究的热点。目前,金属有机气相沉积(MOCVD)、分子束外延(MBE)和氢化物气相外延(HVPE)等方法己经成为制备GaN的主流工艺,其中MOCVD使用的最为广泛。采用上述方法制备GaN,工艺复杂,设备昂贵,限制了GaN材料的制备、生产和应用。现在,国际上有许多科研机构正在探索新的工艺方法,试图在合适的衬底上制备高质量的GaN薄膜。目前GaN基器件大多数制作在蓝宝石衬底上。由于蓝宝石价格昂贵、衬底自身绝缘且硬度大、器件工艺复杂、制作成本费用高,且由于它导热性能差,不利于大功率器件的制作,硅衬底则可以弥补这些不足。因此,开展Si基GaN薄膜材料的外延生长意义重大。虽然以Si为衬底的六方GaN材料的生长有一定难度,但由于其晶体质量高、价格低廉、易解理、导电性好和成熟的Si基集成技术等优点,成为蓝宝石衬底强有力的竞争者。
本文介绍了采用氨化磁控溅射Ga_2O_3/Ta薄膜的方法在硅衬底上合成了GaN纳米结构的方法。并以扫描电镜(SEM)为主,结合透射电镜及高分辨电镜、X射线衍射、红外吸收等手段,研究了纳米线的形貌、显微结构、成分等,并对其生长机制进行了初步探索。研究了不同的氨化温度、不同的氨化时间和不同中间层厚度对GaN纳米线的影响。首先我们利用磁控溅射系统先在Si衬底上制备Ga_2O_3/Ta薄膜,然后在氨气氛
围中退火制备GaN纳米结构。测试结果表明:合成的纳米结构为六方纤锌矿结构的GaN;氨化温度、氨化时间和Ta薄膜的厚度都对一维GaN纳米结构的结晶质量和形貌产生很大的影响。随着氨化温度的升高,GaN纳米结构的直径先减小并有棉絮状晶体生成,后来直径又增大且表面趋于相对光滑;纳米结构的结晶质量也逐渐提高。其中,退火温度为1000℃时,样品的结晶质量和表面形貌最佳。但是,当温度继续升高(高于1000℃),氮化镓纳米线的数量会减少并且结晶质量也会下降。从氨化时间上看,10min所得结果相对较好。另外选用不同的中间层厚度,发现得到的纳米结构形貌各异,说明中间层的厚度对一维GaN纳米结构的合成也有很大的影响。GaN纳米结构的生长机制可初步归结为气体—液体—固体(VLS)生长机制,其中高温下Ta薄膜在高温下会破裂并会在Si衬底上形成纳米液滴,对GaN纳米线的生长起到重要作用。
Gallium nitride (GaN) is an excellent chemical semiconductor material and also is one of the most advanced semiconductors in the world. In fact, GaN has been regarded as one of the most promising materials for the fabrication of opto-electronic devices operating in the blue and near-ultraviolet (UV) regions, for instance light-emitting diodes (LEDs) and laser diodes (LDs), because it has large direct energy band gap of 3.4 eV at room temperature. These light sources have promising applications and potential market demands for the high-density storage of opto-information, high-speed laser print, high-brightness and dynamic display in all colors, solid light sources, signal detectors and communication. In addition, GaN has been attracted much attention as a candidate for fabrication of high temperature, high frequency and high power devices. After 1990, the realization of some pivotally technieal methods and the development of materials growth and devices technics made GaN to be the research focus of the world. MOCVD, MBE and HVPE have become dominating techniques to grow GaN materials. Among these methods, MOCVD is the most important and widely used by researchers. But now large-scale application of GaN devices is confined for the reason of costly equipments and complicated technics. Many research institutes and universities in the world are trying to grow GaN materials with simple and lower cost methods.
In this paper, GaN one-dimensional nanostructures were prepared through magnetron sputtering and ammoniating progress on Si (111) substrates. The morphology, microstructure, and components of nanostructures were analyzed through scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Fourier transformed infrared spectra (FTIR) and X-ray photoelectron spectra (XPS) and so on. We also have a primary discussion about the growth progress of GaN nanostructures.The effects on GaN nanostructures, which stem from various experimental conditions such as the thickness of the middle layer, ammoniating temperature and ammoniating time, were discussed.
Firstly, Ga2O3/Ta film is deposited on Si (111) substrates by magnetron sputtering system, and then GaN nanostructures were fabricated through ammoniating. The results of these tests indicated that the as-synthesized GaN nanostructures were hexagonal GaN with wurtzite structure. The crystalline quality and morphology of GaN nanostructures were greatly influnced by the ammoniating temperature, ammoniating time and the thickness of the Ta films. With the increase of temperature, the diameter of GaN nanostructures was decreased and some batt-shaped crystals were formed, and then the diameter of GaN nanostructures was increased and these GaN nanostructures changed to be relative smooth. The crystalline quality of these GaN nanostructures was also improved. The samples annealed at 1000℃for 10min exhibited the best crystal quality and morphology. But the crystalline quality falled and the amount of these GaN nanostructures decreased when the temperature keep on increasing(above 1000℃).We can get the best results when the ammoniating time is 10min. Nanostructures with different morphology were fabricated by this sputtering-post-annealing technique with the help of Ta films with different thickness as middle layers. A VLS mechanism was possible valid in the growth process of GaN nanostructures in this method. The Ta film broke up, and then the liquid Ta nanodroplets which act as energetically favorable sites for absorption of gas-phase reactants are formed on the Si surface at high temperature, which may plays an important role in the formation of GaN nanostructures.
本文介绍了采用氨化磁控溅射Ga_2O_3/Ta薄膜的方法在硅衬底上合成了GaN纳米结构的方法。并以扫描电镜(SEM)为主,结合透射电镜及高分辨电镜、X射线衍射、红外吸收等手段,研究了纳米线的形貌、显微结构、成分等,并对其生长机制进行了初步探索。研究了不同的氨化温度、不同的氨化时间和不同中间层厚度对GaN纳米线的影响。首先我们利用磁控溅射系统先在Si衬底上制备Ga_2O_3/Ta薄膜,然后在氨气氛
围中退火制备GaN纳米结构。测试结果表明:合成的纳米结构为六方纤锌矿结构的GaN;氨化温度、氨化时间和Ta薄膜的厚度都对一维GaN纳米结构的结晶质量和形貌产生很大的影响。随着氨化温度的升高,GaN纳米结构的直径先减小并有棉絮状晶体生成,后来直径又增大且表面趋于相对光滑;纳米结构的结晶质量也逐渐提高。其中,退火温度为1000℃时,样品的结晶质量和表面形貌最佳。但是,当温度继续升高(高于1000℃),氮化镓纳米线的数量会减少并且结晶质量也会下降。从氨化时间上看,10min所得结果相对较好。另外选用不同的中间层厚度,发现得到的纳米结构形貌各异,说明中间层的厚度对一维GaN纳米结构的合成也有很大的影响。GaN纳米结构的生长机制可初步归结为气体—液体—固体(VLS)生长机制,其中高温下Ta薄膜在高温下会破裂并会在Si衬底上形成纳米液滴,对GaN纳米线的生长起到重要作用。
Gallium nitride (GaN) is an excellent chemical semiconductor material and also is one of the most advanced semiconductors in the world. In fact, GaN has been regarded as one of the most promising materials for the fabrication of opto-electronic devices operating in the blue and near-ultraviolet (UV) regions, for instance light-emitting diodes (LEDs) and laser diodes (LDs), because it has large direct energy band gap of 3.4 eV at room temperature. These light sources have promising applications and potential market demands for the high-density storage of opto-information, high-speed laser print, high-brightness and dynamic display in all colors, solid light sources, signal detectors and communication. In addition, GaN has been attracted much attention as a candidate for fabrication of high temperature, high frequency and high power devices. After 1990, the realization of some pivotally technieal methods and the development of materials growth and devices technics made GaN to be the research focus of the world. MOCVD, MBE and HVPE have become dominating techniques to grow GaN materials. Among these methods, MOCVD is the most important and widely used by researchers. But now large-scale application of GaN devices is confined for the reason of costly equipments and complicated technics. Many research institutes and universities in the world are trying to grow GaN materials with simple and lower cost methods.
In this paper, GaN one-dimensional nanostructures were prepared through magnetron sputtering and ammoniating progress on Si (111) substrates. The morphology, microstructure, and components of nanostructures were analyzed through scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Fourier transformed infrared spectra (FTIR) and X-ray photoelectron spectra (XPS) and so on. We also have a primary discussion about the growth progress of GaN nanostructures.The effects on GaN nanostructures, which stem from various experimental conditions such as the thickness of the middle layer, ammoniating temperature and ammoniating time, were discussed.
Firstly, Ga2O3/Ta film is deposited on Si (111) substrates by magnetron sputtering system, and then GaN nanostructures were fabricated through ammoniating. The results of these tests indicated that the as-synthesized GaN nanostructures were hexagonal GaN with wurtzite structure. The crystalline quality and morphology of GaN nanostructures were greatly influnced by the ammoniating temperature, ammoniating time and the thickness of the Ta films. With the increase of temperature, the diameter of GaN nanostructures was decreased and some batt-shaped crystals were formed, and then the diameter of GaN nanostructures was increased and these GaN nanostructures changed to be relative smooth. The crystalline quality of these GaN nanostructures was also improved. The samples annealed at 1000℃for 10min exhibited the best crystal quality and morphology. But the crystalline quality falled and the amount of these GaN nanostructures decreased when the temperature keep on increasing(above 1000℃).We can get the best results when the ammoniating time is 10min. Nanostructures with different morphology were fabricated by this sputtering-post-annealing technique with the help of Ta films with different thickness as middle layers. A VLS mechanism was possible valid in the growth process of GaN nanostructures in this method. The Ta film broke up, and then the liquid Ta nanodroplets which act as energetically favorable sites for absorption of gas-phase reactants are formed on the Si surface at high temperature, which may plays an important role in the formation of GaN nanostructures.
引文
[1] G.Kipshidze, B.Yavich, A.Chandolu, et al., Controlled growth of GaN nanowires by pulsed metalorganic chemical vapor deposition. Appl. Phys. Lett. 2005, 86: 1
[2] X.M.Cai, A.B. Djuri?i?, and M.H. Xiea, Growth mechanism of stacked-cone and smooth-surface GaN nanowires. Appl. Phys. Lett. 2005, 87: 183103
[3] S. Biswas, S. Kar, T. Ghoshal, et al., Fabrication of GaN nanowirbbons by a catalyst assisted vapor-liquid-solid process. Mater.Research Bulletin. 2007, 42: 428
[4] J.I. Pankove, T.D.Moustakas, “Gallium Nitride (GaN) 1”, Academic Press, 1998.
[5] R.D.Vispute, V. Talyansky, Z. Trajanovic, S. Choopun, M.Downes, R.P.Sharma, T.Venkatesan, M.C.Woods, R.T.Lareau, K.A.Jones, A.A.Iliadis, High quality crystalline ZnO buffer layers on sapphire (001) by pulsed laser deposition for III-V nitrides. Appl.Phys.Lett, 1997, 70: 2735
[6] R. Fischer, A. Miehr, O. Ambacher, T. Metzger, E. Born, Novel single source precursors for MOCVD of AlN, GaN and InN. J.Cryst.Growth, 1997, 170: 139
[7] Y.Xie, Y.Qian, S.Zhang , W. Wang, X. Liu, Y.Zhang, Coexistence of wurtzite GaN with zinc blende and rocksalt studied by x-ray power diffraction and high-resolution transmission electron microscopy. Appl. Phys. Lett. 1996, 69: 334
[8] D.C. Hays, H. Cho, K.B. Jung, C.R. Abernathy, S.J. Pearton, Selective dry etchingusing inductively coupled plasmas: Part II InN/GaN and InN/AIN. Appl. Surf. Sci, 1999, 147(1-4): 134
[9] Adesida I., Mahajan A., Andideh E., Asif Khan M. , Olsen D.T. , and Kuznia J.N., Reactive ion etching of gallium nitride in silicon tetrachloride plasmas. Appl.Phys.Lett, 1993, 63(20):2777-2779
[10] X.G. Qiu, Y. Segawa, Q. K. Xue, Q. Z. Xue, and T. Sakurai, Influence of threading dislocations on the near-bandedge photoluminescence of wurtzite GaN thin films on SiC substrate. Appl. Phys. Lett, 2000, (77): 316-1318
[11] V. Kirilyuk, A. R. A. Zauner, P. C. M. Christianen, J. L. Weyher, P. R. Hageman, P.K. Larsen, Exciton-related photoluminescence in homoepitaxial GaN of Ga and N polarities. Appl. Phys. Lett, 2000, (76):2355
[12] J. I. Pankove, J. E. Berkeyheiser, H. P. Maruska, J. Wittke, Luminescent properties of GaN. Solid State Communications, 1970, (8):1051
[13] H.G. Grimmeiss, B.Monemar, Low-temperature luminescence of GaN. J.Appl.Phys, 1970, (41): 4054
[14] E.M. Levinshtein, S.L. Rumyantsev, M.S. Shur, 先进半导体材料性能与数据手册 (2003)
[15] S.Nakamura, T.Mukai and M.Senoh, In situ monitoring and Hall measurements of GaN grown with GaN buffer layers. J. Appl. Phys, 1992, 71:5543-5549
[16] M. Asif Khan, J.N. Kuznia, J.M. Van Hove, D.T. Olson, S.Krishnankutty and R.M. Kolbas. Growth of high optical and electrical quality GaN layer using low-pressure metalorganic chemical vapor deposition. Appl. Phys. Lett., 1991, 58:526-527
[17] H.Amano, M. Kito, K.Hiramatsu and I.Akasaki. P-type conduction in Mg-doped GaN treated with low-energy electron beam irradiation (LEEBI), Japanese Journal of Applied Physics, 1989, 28:L2112-L2114
[18] S.Nakamura, T.Mukai, M .Senoh and N.Iwasa, Thermal annealing effects on P-type Mg-doped GaN films. Japanese Journal of Applied Physics, 1992, 31:139-L142
[19] S.Gu, R.Zhang, Y.Shi, et al., The impact of initial growth and substrate nitridation on thick GaN growth on sapphire by hydride vapor phase epitaxy, J.Cryst. Growth, 2001, 231(3):342-351.
[20] H. Amano, I. Akasaki, K. Hiramatsu, et al., Effects of the buffer layer in metalorganic Vapour phase epitaxy of GaN on Sapphire substrate, Thin Solid Films, 1988, 163: 415-420.
[21] S.Nakamura, M.Senoh, S.Nagahama, et al., InGaN/GaN/AlGaN-based laser diodes with modulation-doped strained-layer superlattices. Jpn.J.Appl.Phys, 1997, 36:L1518-L1571.
[22] W.Kim, Q.ktas, A. E. Botchkarev, et al., Reactive molecular beam epitaxy of wurtzite GaN: Materials Characteristics and growth kinetics, J. Appl. Phys.,1996:79(10):7657-7666.
[23] Sung Hwan Cho, Uitsu Tanaka, Kazutaka Hata, et al., Photoluminescence properties of GaN Grown under Ion Flux Reduced Condition by Plasma Enhanced Molecular Beam EpitaxyJpn.J.Appl.Phys.,1996;35:L644-L647.
[24] Q.Chen, M.A Khan, J.W. Yang, et al., High transconductance heterostructure field-effect transistors based on AlGaN/GaN. Applied Physics Letters, 1996, 69(6):794-796
[25] Y. Huang, X.F. Duan, C.M. Lieber, Gallium Nitride Nanowire Nanodevices. Nano Lerrer, 2002, 2:101-104
[26] F.A. Ponce, D.P. Bour, Nitride-based semiconductors for blue and green light-emitting devices. Nature, 1997, 386:351-359.
[27] S Nakamura, M Senoh, S Nagahama, et al., InGaN/GaN/AlGaN-based laser diodes with modulation-doped strained-layer superlattices grown on an epitaxially laterally overgrown GaN substrate. Applied Physics Letters, 1998, 72(2):211-213
[28] V Ucakar, W Lengauer, D Rafaja, Preparation of thick GaN layers by chemical vapour deposition for contact reaction investigations. Diamond and Related. Materials,2000,9:464一466
[29] Y Fu, Y.P. Sun, Growth of cubic GaN by MOCVD at high temperature. Semiconductors,2002,23(2):120一123.
[30] T Takashi, W Akihior, N Susumu, et al., Substrate nitridation effect and low temperature growth of GaN on sapphier(0001) by plasma-excited Organometallic vapor-phasee pitaxy. Journal of Crystal Growth,1998,183:62一68
[31] G.Zhang, Z.Yang, Y.Tong, et al., P-type GaN directly growth by low pressure metalorganic vapor phase epitaxy. Chinese Physical Letters,1997, 14(8):637一640
[32] Sun DZ, Wang XL, Wang JX. Preparation of high quality GaN by GSMBE.Ch inese Journal of Semiconductors,2000,21(7):723一725.
[33] S Akira, K Akitaka, Microstructuer of GaN films on GaAs (100) su bstrates grown by hydride vapor-phase epitaxy. Journal of Crystal Growth,1998,183:49-61
[34] M Kensaku, O Takuji, Preparation of large freestanding GaN substrates by hydride vapor phase epitaxy using GaAs as a starting substrate. Japanese Journal ofApplied Physics,2001,40:140一143
[35] W Zhang, T Riemann, H.R. Alves, et al. Modulated growth of thick GaN with hydride vapor phase epitaxy. Journal of Crystal Growth, 2002, 234:616-622
[36] L.D. Zhu, P.H Maruska, P.E. Norris, et al., Bouthillette, Epitaxial growth and structural characterization of single crystalline ZnGaN2. Mrs Internet Journal of Nitride Semiconductor Research, 1999,4(G3.8):1一9
[37] S.Nakamura, GaN Growth Using Buffer Layer, Jpn. J. Appl. Phys. 1991, 30:L1705
[38] H. Amano, M. Kito, K. Hiramatsu and I. Akasaki, P-Type Conduction in Mg-Doped GaN Treated with Low-Energy Electron Beam Irradiation (LEEBI), Jpn. J. Appl. Phys. 1989, 28:L2112~ L2114
[39] S. Nakamura, M. Senoh, T. Mukai, Highly P-Typed Mg-Doped GaN Films Grown with GaN Buffer Layers, Jpn. J. Appl. Phys. 1991, 30: L1708~L1711
[40] S. Nakamura, T. Mukai, M. Senoh, N. Iwasa, Thermal Annealing Effects on P-Type Mg-Doped GaN Films, Jpn. J. Appl. Phys. 1992, 31:L139~L142
[41] S. Nakamura, N. Iwasa, M. Senoh and T. Mukai, Hole Compensation Mechanism of P-Type GaN Films, Jpn. J. Appl. Phys. 1992, 31,1258~1266
[42] J. I. Pankove, E. A. Miller, J. E. Berkeyheiser, GaN electroluminescent diodes, RCA Rev. 1971,32: 383
[43] S. Nakamura, M. Senoh, S. Naghama, N. Iwasa, T. Yamada, T. Matsushita, H. Kiyoku and Y. Sugimoto, InGaN-Based Multi-Quantum-Well-Structure Laser Diodes, Jpn. J. Appl. Phys. 1996, 35: L74~L76
[44] S. Nakamura, M. Senoh, S. Naghama, N. Iwasa, T. Yamada, T. Matsushita, V. Sugimotlo and H. Kiyoku, Room-temperature continuous-wave operation of InGaN multi-quantum-well structure laser diodes with a lifetime of 27 hours, Appl. Phys. Lett.1997, 70: 1417 ~1419.
[45] P.Sanguino, M.Niehus, L.V.Melo, et al. Characterisation of GaN films grown on sapphire by low-temperature cyclic pulsed laser deposition/nitrogen r.f. plasma. Solid-state Electronics, 2003, 47(3): 559-563
[46] Q. Xue, Q.K. Xue, R.Z. Bakhtizin, Atomistic investigation of various GaN (0001) phases on the 6H-SiC (0001) surface. Physical Review B, 1999, 59(19): 12604-12611
[47] H.Ishikawa, K.Yamamoto, T.Egawa, et al., Thermal stability of GaN on (111) Si substrate. J.Cryst.Growth, 1998, 189-190:178-182
[48] A.Georgakilasa, K.Amimera, P.Tzanetakisa, et al., Correlation of the structural and optical properties of GaN grown on vicinal (001) GaAs substrates with the plasma-assisted MBE growth conditions. J.Cryst.Growth, 2001, 227: 410-414
[49] F.Hamdani, M.Yeadon, D. J.Smith, et al., Microstructure and optical properties of epitaxial GaN on ZnO (0001) grown by reactive molecular beam epitaxy. J. Appl. Phys., 1998, 83 (2): 983-990
[50] S.Michael, A.Mohamed, Optoelectronic GaN-based field effect transistors, Proc. SPIE 1995, 2397:294~303
[51] C.C. Chen, C.C. Yeh, Large-Scale Catalytic Synthesis of Crystalline Gallium Nitride Nanowires, Adv. Mater 2000, 12(10): 738-741
[52] C. N. R. Rao, F. L. Deepak, Gautam Gundiah, A. Govindaraj, Inorganic nanowires, Progress in Solid State Chemistry 2003, 31:5~147
[53] W.Q. Han, A. Zettl, Pyrolysis approach to the synthesis of gallium nitride nanorods, Appl. Phys. Lett. 2002, 80(2):303~305
[54] W. S. Shi, Y. F. Zheng, N. Wang, C. S. Lee and S. T. Lee, Microstructures of gallium nitride nanowires synthesized by oxide-assisted method,Chem. Phys. Lett. 2001, 345: 377~380
[55] W. Han, S. Fan, Q .Li, Y. Hu, Synthesis of Gallium Nitride Nanorods Through a Carbon Nanotube-Confined Reaction, Science 1997, 277:1287~1289.
[56] R.S.Wagner and W.C.Ellis, Vapor-Liquid-Solid mechanism of single crystal growth, Appl. Phys. Lett., 1964, 4:89-91
[57] S.T.Lee, N.Wang, Y.F.Zhang and Y.H.Tang, Oxide-assisted semiconductor nanowire growth, MRS Bull, 1999, 24(8):36-42
[58] N Wang, Y.H. Tang, Y.F. Zhang, et al. Nucleation and growth of Si nanowires from silicon oxide, Phys Rev B 1998, 58:R16024–R16026
[59] Y.G. Sun, Y.D. Yin, B.T. Mayers, et al., Uniform Silver Nanowires Synthesies by Reducing AgNO3 with Ethylene Glycol in the Presence of Seed and Poly Chem.Mater. ,2002 ,14(11) :4 736～4 745
[60] E.Matijevic, Uniform Silver Nanowires Synthesis by Reducing AgNO3 with Ethylene Glycol in the Presence of Seeds and Poly (Vinyl Pyrrolidone). Chem. Mater., 1993, 5(4):412～426
[61] T.J.Trentler, K.M. Hickman, S.C. Goel, et al., Solution-Liquid-Solid Growth of Crystalline III-V Semiconductors2 An Analogy to Vapor-Liquid-Solid Growth. Science ,1995 ,270 (5243) :1 791～1 794
[62] D Zhou, S Seraphin, Production of Silicon-Carbide Whiskers from Carbon Nan- oclusters. Chem. Phys. Lett., 1994, 222 (3):223～238
[63] H.J. Dai, E.W. Wong, Y.Z. Lu, et al., Synthesis and Characterization of Carbide Nanorods. Nature ,1995 ,375(6534) :769～772
[64] W.Han, S.Fan, Q.Li, Synthesis of gallium nitride Nanorods through a carbon nanotube–confined reaction. Science, 1997, 277: 1287-1289
[65] G.S.Cheng, L.D.Zhang, Y.Zhu, et al., Large-scale synthesis of single crystalline gallium nitride nanowires. Appl. Phy. Lett 1999, 75(16): 2455-2457
[66] G.S.Cheng, S.H.Chen, X.G.Zhu, Y.Q.Mao, L.D.Zhang, Highly ordered nanostructures of sigle crystalline GaN nanowires. Mater Sci & Eng A, 2000, 286: 165-168
[67] J.Goldberger, R.He, Y.F. Zhang, Single-crystal gallium nitride nanotubes. Nature, 2003, 422: 599-602
[68] X.L. Chen, J.Y. Li, Y.G. Cao, Y.C. Lan, H. Li, et al., Straight and smooth GaN naowires. Adv. Mater., 2000, 12(19):1432
[69] J.Y. Li, X.L. Chen, Z.Y. Qiao, Y.G. Cao, et al., Synthesis of aligned gallium nitride nanowire quasi-arrays. Appl. Phys. A, 2000, 71:349-350
[70] J.Y. Li, X.L. Chen, Y.G. Cao, Z.Y. Qiao, Y.C. Lan, Raman-scattering spectrum of GaN straight nanowires. Appl. Phys. A, 2000, 71:345-346
[71] X.L. Chen, Y.C. Lan, J.Y. Li, Y.G. Cao, M.He, Radial growth dynamics of nanowires. J. Cryst. Growth 2001, 222:586-590
[72] H.Li, J.Y. Li, M.He, et al., Fabrication of bamboo-shaped GaN nanorods. Appl. Phys A 2002, 74: 561-562
[73] J.C. Wang, S.O. Feng, D.P. Yu, High-quality GaN nanowire synthesized using a CVD approach. Appl. Phys. A 2002, 75: 691-693
[74] X.L. Chen, J.Y. Li, Y.C. Lan, Y.G. Cao, Morphological stability of a nanowire during growth process. Modern Phys. Lett. B, 2001, 15:27-31
[75] Y. S. Park, C. M. Park, D. J. Fu, et al., Photoluminescence of GaN nanorods on Si(111) substrates grown by molecular-beam epitaxy. APPL. PHYS. LETT 2004, 85: 5178-5120
[76] J.Kim, O. Hwangyou, H.Miso, et al., Rectifying diode made of individual nitride nanowire. Physica E 2003, 18: 225-226.
[77] Y. Huang, X. Duan, Y. Cui, C. M. Lieber, “Gallium nitride nanowire nanodevices”, Nano Lett., 2002, 2: 101.
[78] E. Stern, G. Cheng, E. Cimpoiasu, et al., Electrical characterization of single GaN nanowires, Nanotechnology, 2005, 16:2941
[79] J. M. Barker, K. A. Bertness, N. A. Sanford, Electrical measurements of GaN nanowires deposited using electric-field assisted alignment 6th International Conference on Nitride Semiconductors, Tu-P-123.
[80] Y. Huang, X. Duan, Y. Cui, L. J. Lauhon, K. H. Kim, C. M. Lieber, Logic gates and computation from assembled nanowire building blocks, Science, 2001, 294:1313
[81] F. Qian, S. Gradecak, Y. Li, C. Wen, et al., Core/Multishell nanowire heterostructures as multicolor, high-efficiency light-emitting diodes, Nano Lett, 2005, 5:2287
[82] S.Gradecak, F.Qian, Y.Li, H.G. Park, et al., GaN nanowire lasers with low lasing thresholds, Appl. Phys. Lett, 2005, 87: 173111
[83] J.H. Boo, C. Rohr, W. Ho, MOCVD of BN and GaN thin films on silcon: new attempt of GaN growth with BN buffer layer [J]. J. Cryst.Growth 1998; 189/190: 439-444.
[84] Y. Sun, T. Miyasato, N. Snoda. Outdiffusion of the excess carbon in SiC films intoSi substrate during film growth [J]. J. Appl. Phys, 1998; 84: 6451.
[85] R.Ding, H.Wang, Microsturcture and optical properties of GaAs/SiO2 nanogranular films prepared by magnetron co-sputtering [J]. Materials Chemistry and Physics, 2003; 77: 841.
[86] W.K. Choi, T.Y. Ong, L.S. Tan, F.C. Loh and K.L. Tan, Infrared and X-ray photoelectron studies of as-prepared and furnace-annealed radio-frequency sputtered amorphous silicon carbide films, J. Appl. Phys1998, 83(9):4968
[87] D Li, M Sumiys, S Fuke, Selective etching of GaN polar surface in potassium hydroxide solution studied by x-ray photoelectron spectroscopy. J. Appl. Phys., 2001, 90(8): 4219-4223
[88] T.D.Veal, I.Mahboob, L.F.J. Piper, C.F. McConville. Core-level photoemission spectroscopy of nitrogen bonding in GaNxAs1-X alloys. Appl. Phys. Lett., 2004, 85(9): 1550-1552
[89] N. Elkashef, R.S. Srinivasa, S. Major, S.C. Sabharwal, K.P. Muthe, Sputter depositon of gallium nitride films using a GaAs target, Thin Solid Films1998,333:9
[90] C.R. Kingsley, T.J. Whitaker, A.T.S. Wee et al.,Development of chem.ical beam epitaxy for the depositon of gallium nitride, Mater. Sci. Eng 1995, B29:78-82
[91] T. Sasaki, T. Matsuoka, Substrate-polarity dependence of metalorganic vapor phase epitaxy grown GaN on SiC, J. App. Phys 199864:4531
[92] H Ishikawa, S Kobayashi, Y Koide, S Yamasaki, S Nagai, J Umezaki, M Koike, M Murakami, Effects of surface treatments and metal work functions on electrical properties at p-GaN/metal interfaces. J. Appl. Phys., 1997, 81(3): 1315-1322
[93] F.M. Amanullah, K.J.Pratap, V. Hari babu, Compositonal analysis and depth profile studies on undoped and doped tin oxide films prepared by spray technique, Mater. Sci. Eng. B1998, 52:93
[94] T.J.Ghang, C.R.brundle, D.W. Rice, Interpretation of the X-ray photoemission spectra of cobalt oxides and cobalt oxide surfaces, Surf. Sci. 1979, 59:413
[95] R.Y. Korotkov, M.A. Reshchikov, B.W. Wessels, Physica B 273, 80 (1999)
[96] B.Monemar, Fundamental energy gap of GaN from photoluminescence excitations pectra [J]. Phys.Rev, 1974, B10: 676-681
[97] Y.G. Yang, H.L. Ma, C.S. Xue, et al., Preparation and structural properties for GaN films grown on Si (111) by annealing. Applied Surface Science, 2002, 193: 254-260
[98] B.S. Simpkins, L.M. Ericson, R.M. Stroud, K.A.Pettingrew, P.E. Pehrsson, J. Cryst. Growth 2006, 290: 115-120
[99] C.M.Balkas, R.F. Davis, Synthesis Routes and Characterization of High-purity, Single-phase Gallium Nitride Powders, J. Am. Ceram. Soc,1996, 79, 2309-12
[100] W.S. Jung, Reaction Intermediate(s) in the Conversion of b-gallium Oxide to Gallium Nitride Under a Flow of Ammonia, Mater. Lett, 2002, 57, 110-114
[101] T.Y. Kim, S.H Lee, Y.H Mo, et al. Growth of GaN nanowires on Si substrate using Ni catalyst in vertical chemical vapor deposition reactor. J. Crystal Growth, 2003, 257: 97-103
[2] X.M.Cai, A.B. Djuri?i?, and M.H. Xiea, Growth mechanism of stacked-cone and smooth-surface GaN nanowires. Appl. Phys. Lett. 2005, 87: 183103
[3] S. Biswas, S. Kar, T. Ghoshal, et al., Fabrication of GaN nanowirbbons by a catalyst assisted vapor-liquid-solid process. Mater.Research Bulletin. 2007, 42: 428
[4] J.I. Pankove, T.D.Moustakas, “Gallium Nitride (GaN) 1”, Academic Press, 1998.
[5] R.D.Vispute, V. Talyansky, Z. Trajanovic, S. Choopun, M.Downes, R.P.Sharma, T.Venkatesan, M.C.Woods, R.T.Lareau, K.A.Jones, A.A.Iliadis, High quality crystalline ZnO buffer layers on sapphire (001) by pulsed laser deposition for III-V nitrides. Appl.Phys.Lett, 1997, 70: 2735
[6] R. Fischer, A. Miehr, O. Ambacher, T. Metzger, E. Born, Novel single source precursors for MOCVD of AlN, GaN and InN. J.Cryst.Growth, 1997, 170: 139
[7] Y.Xie, Y.Qian, S.Zhang , W. Wang, X. Liu, Y.Zhang, Coexistence of wurtzite GaN with zinc blende and rocksalt studied by x-ray power diffraction and high-resolution transmission electron microscopy. Appl. Phys. Lett. 1996, 69: 334
[8] D.C. Hays, H. Cho, K.B. Jung, C.R. Abernathy, S.J. Pearton, Selective dry etchingusing inductively coupled plasmas: Part II InN/GaN and InN/AIN. Appl. Surf. Sci, 1999, 147(1-4): 134
[9] Adesida I., Mahajan A., Andideh E., Asif Khan M. , Olsen D.T. , and Kuznia J.N., Reactive ion etching of gallium nitride in silicon tetrachloride plasmas. Appl.Phys.Lett, 1993, 63(20):2777-2779
[10] X.G. Qiu, Y. Segawa, Q. K. Xue, Q. Z. Xue, and T. Sakurai, Influence of threading dislocations on the near-bandedge photoluminescence of wurtzite GaN thin films on SiC substrate. Appl. Phys. Lett, 2000, (77): 316-1318
[11] V. Kirilyuk, A. R. A. Zauner, P. C. M. Christianen, J. L. Weyher, P. R. Hageman, P.K. Larsen, Exciton-related photoluminescence in homoepitaxial GaN of Ga and N polarities. Appl. Phys. Lett, 2000, (76):2355
[12] J. I. Pankove, J. E. Berkeyheiser, H. P. Maruska, J. Wittke, Luminescent properties of GaN. Solid State Communications, 1970, (8):1051
[13] H.G. Grimmeiss, B.Monemar, Low-temperature luminescence of GaN. J.Appl.Phys, 1970, (41): 4054
[14] E.M. Levinshtein, S.L. Rumyantsev, M.S. Shur, 先进半导体材料性能与数据手册 (2003)
[15] S.Nakamura, T.Mukai and M.Senoh, In situ monitoring and Hall measurements of GaN grown with GaN buffer layers. J. Appl. Phys, 1992, 71:5543-5549
[16] M. Asif Khan, J.N. Kuznia, J.M. Van Hove, D.T. Olson, S.Krishnankutty and R.M. Kolbas. Growth of high optical and electrical quality GaN layer using low-pressure metalorganic chemical vapor deposition. Appl. Phys. Lett., 1991, 58:526-527
[17] H.Amano, M. Kito, K.Hiramatsu and I.Akasaki. P-type conduction in Mg-doped GaN treated with low-energy electron beam irradiation (LEEBI), Japanese Journal of Applied Physics, 1989, 28:L2112-L2114
[18] S.Nakamura, T.Mukai, M .Senoh and N.Iwasa, Thermal annealing effects on P-type Mg-doped GaN films. Japanese Journal of Applied Physics, 1992, 31:139-L142
[19] S.Gu, R.Zhang, Y.Shi, et al., The impact of initial growth and substrate nitridation on thick GaN growth on sapphire by hydride vapor phase epitaxy, J.Cryst. Growth, 2001, 231(3):342-351.
[20] H. Amano, I. Akasaki, K. Hiramatsu, et al., Effects of the buffer layer in metalorganic Vapour phase epitaxy of GaN on Sapphire substrate, Thin Solid Films, 1988, 163: 415-420.
[21] S.Nakamura, M.Senoh, S.Nagahama, et al., InGaN/GaN/AlGaN-based laser diodes with modulation-doped strained-layer superlattices. Jpn.J.Appl.Phys, 1997, 36:L1518-L1571.
[22] W.Kim, Q.ktas, A. E. Botchkarev, et al., Reactive molecular beam epitaxy of wurtzite GaN: Materials Characteristics and growth kinetics, J. Appl. Phys.,1996:79(10):7657-7666.
[23] Sung Hwan Cho, Uitsu Tanaka, Kazutaka Hata, et al., Photoluminescence properties of GaN Grown under Ion Flux Reduced Condition by Plasma Enhanced Molecular Beam EpitaxyJpn.J.Appl.Phys.,1996;35:L644-L647.
[24] Q.Chen, M.A Khan, J.W. Yang, et al., High transconductance heterostructure field-effect transistors based on AlGaN/GaN. Applied Physics Letters, 1996, 69(6):794-796
[25] Y. Huang, X.F. Duan, C.M. Lieber, Gallium Nitride Nanowire Nanodevices. Nano Lerrer, 2002, 2:101-104
[26] F.A. Ponce, D.P. Bour, Nitride-based semiconductors for blue and green light-emitting devices. Nature, 1997, 386:351-359.
[27] S Nakamura, M Senoh, S Nagahama, et al., InGaN/GaN/AlGaN-based laser diodes with modulation-doped strained-layer superlattices grown on an epitaxially laterally overgrown GaN substrate. Applied Physics Letters, 1998, 72(2):211-213
[28] V Ucakar, W Lengauer, D Rafaja, Preparation of thick GaN layers by chemical vapour deposition for contact reaction investigations. Diamond and Related. Materials,2000,9:464一466
[29] Y Fu, Y.P. Sun, Growth of cubic GaN by MOCVD at high temperature. Semiconductors,2002,23(2):120一123.
[30] T Takashi, W Akihior, N Susumu, et al., Substrate nitridation effect and low temperature growth of GaN on sapphier(0001) by plasma-excited Organometallic vapor-phasee pitaxy. Journal of Crystal Growth,1998,183:62一68
[31] G.Zhang, Z.Yang, Y.Tong, et al., P-type GaN directly growth by low pressure metalorganic vapor phase epitaxy. Chinese Physical Letters,1997, 14(8):637一640
[32] Sun DZ, Wang XL, Wang JX. Preparation of high quality GaN by GSMBE.Ch inese Journal of Semiconductors,2000,21(7):723一725.
[33] S Akira, K Akitaka, Microstructuer of GaN films on GaAs (100) su bstrates grown by hydride vapor-phase epitaxy. Journal of Crystal Growth,1998,183:49-61
[34] M Kensaku, O Takuji, Preparation of large freestanding GaN substrates by hydride vapor phase epitaxy using GaAs as a starting substrate. Japanese Journal ofApplied Physics,2001,40:140一143
[35] W Zhang, T Riemann, H.R. Alves, et al. Modulated growth of thick GaN with hydride vapor phase epitaxy. Journal of Crystal Growth, 2002, 234:616-622
[36] L.D. Zhu, P.H Maruska, P.E. Norris, et al., Bouthillette, Epitaxial growth and structural characterization of single crystalline ZnGaN2. Mrs Internet Journal of Nitride Semiconductor Research, 1999,4(G3.8):1一9
[37] S.Nakamura, GaN Growth Using Buffer Layer, Jpn. J. Appl. Phys. 1991, 30:L1705
[38] H. Amano, M. Kito, K. Hiramatsu and I. Akasaki, P-Type Conduction in Mg-Doped GaN Treated with Low-Energy Electron Beam Irradiation (LEEBI), Jpn. J. Appl. Phys. 1989, 28:L2112~ L2114
[39] S. Nakamura, M. Senoh, T. Mukai, Highly P-Typed Mg-Doped GaN Films Grown with GaN Buffer Layers, Jpn. J. Appl. Phys. 1991, 30: L1708~L1711
[40] S. Nakamura, T. Mukai, M. Senoh, N. Iwasa, Thermal Annealing Effects on P-Type Mg-Doped GaN Films, Jpn. J. Appl. Phys. 1992, 31:L139~L142
[41] S. Nakamura, N. Iwasa, M. Senoh and T. Mukai, Hole Compensation Mechanism of P-Type GaN Films, Jpn. J. Appl. Phys. 1992, 31,1258~1266
[42] J. I. Pankove, E. A. Miller, J. E. Berkeyheiser, GaN electroluminescent diodes, RCA Rev. 1971,32: 383
[43] S. Nakamura, M. Senoh, S. Naghama, N. Iwasa, T. Yamada, T. Matsushita, H. Kiyoku and Y. Sugimoto, InGaN-Based Multi-Quantum-Well-Structure Laser Diodes, Jpn. J. Appl. Phys. 1996, 35: L74~L76
[44] S. Nakamura, M. Senoh, S. Naghama, N. Iwasa, T. Yamada, T. Matsushita, V. Sugimotlo and H. Kiyoku, Room-temperature continuous-wave operation of InGaN multi-quantum-well structure laser diodes with a lifetime of 27 hours, Appl. Phys. Lett.1997, 70: 1417 ~1419.
[45] P.Sanguino, M.Niehus, L.V.Melo, et al. Characterisation of GaN films grown on sapphire by low-temperature cyclic pulsed laser deposition/nitrogen r.f. plasma. Solid-state Electronics, 2003, 47(3): 559-563
[46] Q. Xue, Q.K. Xue, R.Z. Bakhtizin, Atomistic investigation of various GaN (0001) phases on the 6H-SiC (0001) surface. Physical Review B, 1999, 59(19): 12604-12611
[47] H.Ishikawa, K.Yamamoto, T.Egawa, et al., Thermal stability of GaN on (111) Si substrate. J.Cryst.Growth, 1998, 189-190:178-182
[48] A.Georgakilasa, K.Amimera, P.Tzanetakisa, et al., Correlation of the structural and optical properties of GaN grown on vicinal (001) GaAs substrates with the plasma-assisted MBE growth conditions. J.Cryst.Growth, 2001, 227: 410-414
[49] F.Hamdani, M.Yeadon, D. J.Smith, et al., Microstructure and optical properties of epitaxial GaN on ZnO (0001) grown by reactive molecular beam epitaxy. J. Appl. Phys., 1998, 83 (2): 983-990
[50] S.Michael, A.Mohamed, Optoelectronic GaN-based field effect transistors, Proc. SPIE 1995, 2397:294~303
[51] C.C. Chen, C.C. Yeh, Large-Scale Catalytic Synthesis of Crystalline Gallium Nitride Nanowires, Adv. Mater 2000, 12(10): 738-741
[52] C. N. R. Rao, F. L. Deepak, Gautam Gundiah, A. Govindaraj, Inorganic nanowires, Progress in Solid State Chemistry 2003, 31:5~147
[53] W.Q. Han, A. Zettl, Pyrolysis approach to the synthesis of gallium nitride nanorods, Appl. Phys. Lett. 2002, 80(2):303~305
[54] W. S. Shi, Y. F. Zheng, N. Wang, C. S. Lee and S. T. Lee, Microstructures of gallium nitride nanowires synthesized by oxide-assisted method,Chem. Phys. Lett. 2001, 345: 377~380
[55] W. Han, S. Fan, Q .Li, Y. Hu, Synthesis of Gallium Nitride Nanorods Through a Carbon Nanotube-Confined Reaction, Science 1997, 277:1287~1289.
[56] R.S.Wagner and W.C.Ellis, Vapor-Liquid-Solid mechanism of single crystal growth, Appl. Phys. Lett., 1964, 4:89-91
[57] S.T.Lee, N.Wang, Y.F.Zhang and Y.H.Tang, Oxide-assisted semiconductor nanowire growth, MRS Bull, 1999, 24(8):36-42
[58] N Wang, Y.H. Tang, Y.F. Zhang, et al. Nucleation and growth of Si nanowires from silicon oxide, Phys Rev B 1998, 58:R16024–R16026
[59] Y.G. Sun, Y.D. Yin, B.T. Mayers, et al., Uniform Silver Nanowires Synthesies by Reducing AgNO3 with Ethylene Glycol in the Presence of Seed and Poly Chem.Mater. ,2002 ,14(11) :4 736～4 745
[60] E.Matijevic, Uniform Silver Nanowires Synthesis by Reducing AgNO3 with Ethylene Glycol in the Presence of Seeds and Poly (Vinyl Pyrrolidone). Chem. Mater., 1993, 5(4):412～426
[61] T.J.Trentler, K.M. Hickman, S.C. Goel, et al., Solution-Liquid-Solid Growth of Crystalline III-V Semiconductors2 An Analogy to Vapor-Liquid-Solid Growth. Science ,1995 ,270 (5243) :1 791～1 794
[62] D Zhou, S Seraphin, Production of Silicon-Carbide Whiskers from Carbon Nan- oclusters. Chem. Phys. Lett., 1994, 222 (3):223～238
[63] H.J. Dai, E.W. Wong, Y.Z. Lu, et al., Synthesis and Characterization of Carbide Nanorods. Nature ,1995 ,375(6534) :769～772
[64] W.Han, S.Fan, Q.Li, Synthesis of gallium nitride Nanorods through a carbon nanotube–confined reaction. Science, 1997, 277: 1287-1289
[65] G.S.Cheng, L.D.Zhang, Y.Zhu, et al., Large-scale synthesis of single crystalline gallium nitride nanowires. Appl. Phy. Lett 1999, 75(16): 2455-2457
[66] G.S.Cheng, S.H.Chen, X.G.Zhu, Y.Q.Mao, L.D.Zhang, Highly ordered nanostructures of sigle crystalline GaN nanowires. Mater Sci & Eng A, 2000, 286: 165-168
[67] J.Goldberger, R.He, Y.F. Zhang, Single-crystal gallium nitride nanotubes. Nature, 2003, 422: 599-602
[68] X.L. Chen, J.Y. Li, Y.G. Cao, Y.C. Lan, H. Li, et al., Straight and smooth GaN naowires. Adv. Mater., 2000, 12(19):1432
[69] J.Y. Li, X.L. Chen, Z.Y. Qiao, Y.G. Cao, et al., Synthesis of aligned gallium nitride nanowire quasi-arrays. Appl. Phys. A, 2000, 71:349-350
[70] J.Y. Li, X.L. Chen, Y.G. Cao, Z.Y. Qiao, Y.C. Lan, Raman-scattering spectrum of GaN straight nanowires. Appl. Phys. A, 2000, 71:345-346
[71] X.L. Chen, Y.C. Lan, J.Y. Li, Y.G. Cao, M.He, Radial growth dynamics of nanowires. J. Cryst. Growth 2001, 222:586-590
[72] H.Li, J.Y. Li, M.He, et al., Fabrication of bamboo-shaped GaN nanorods. Appl. Phys A 2002, 74: 561-562
[73] J.C. Wang, S.O. Feng, D.P. Yu, High-quality GaN nanowire synthesized using a CVD approach. Appl. Phys. A 2002, 75: 691-693
[74] X.L. Chen, J.Y. Li, Y.C. Lan, Y.G. Cao, Morphological stability of a nanowire during growth process. Modern Phys. Lett. B, 2001, 15:27-31
[75] Y. S. Park, C. M. Park, D. J. Fu, et al., Photoluminescence of GaN nanorods on Si(111) substrates grown by molecular-beam epitaxy. APPL. PHYS. LETT 2004, 85: 5178-5120
[76] J.Kim, O. Hwangyou, H.Miso, et al., Rectifying diode made of individual nitride nanowire. Physica E 2003, 18: 225-226.
[77] Y. Huang, X. Duan, Y. Cui, C. M. Lieber, “Gallium nitride nanowire nanodevices”, Nano Lett., 2002, 2: 101.
[78] E. Stern, G. Cheng, E. Cimpoiasu, et al., Electrical characterization of single GaN nanowires, Nanotechnology, 2005, 16:2941
[79] J. M. Barker, K. A. Bertness, N. A. Sanford, Electrical measurements of GaN nanowires deposited using electric-field assisted alignment 6th International Conference on Nitride Semiconductors, Tu-P-123.
[80] Y. Huang, X. Duan, Y. Cui, L. J. Lauhon, K. H. Kim, C. M. Lieber, Logic gates and computation from assembled nanowire building blocks, Science, 2001, 294:1313
[81] F. Qian, S. Gradecak, Y. Li, C. Wen, et al., Core/Multishell nanowire heterostructures as multicolor, high-efficiency light-emitting diodes, Nano Lett, 2005, 5:2287
[82] S.Gradecak, F.Qian, Y.Li, H.G. Park, et al., GaN nanowire lasers with low lasing thresholds, Appl. Phys. Lett, 2005, 87: 173111
[83] J.H. Boo, C. Rohr, W. Ho, MOCVD of BN and GaN thin films on silcon: new attempt of GaN growth with BN buffer layer [J]. J. Cryst.Growth 1998; 189/190: 439-444.
[84] Y. Sun, T. Miyasato, N. Snoda. Outdiffusion of the excess carbon in SiC films intoSi substrate during film growth [J]. J. Appl. Phys, 1998; 84: 6451.
[85] R.Ding, H.Wang, Microsturcture and optical properties of GaAs/SiO2 nanogranular films prepared by magnetron co-sputtering [J]. Materials Chemistry and Physics, 2003; 77: 841.
[86] W.K. Choi, T.Y. Ong, L.S. Tan, F.C. Loh and K.L. Tan, Infrared and X-ray photoelectron studies of as-prepared and furnace-annealed radio-frequency sputtered amorphous silicon carbide films, J. Appl. Phys1998, 83(9):4968
[87] D Li, M Sumiys, S Fuke, Selective etching of GaN polar surface in potassium hydroxide solution studied by x-ray photoelectron spectroscopy. J. Appl. Phys., 2001, 90(8): 4219-4223
[88] T.D.Veal, I.Mahboob, L.F.J. Piper, C.F. McConville. Core-level photoemission spectroscopy of nitrogen bonding in GaNxAs1-X alloys. Appl. Phys. Lett., 2004, 85(9): 1550-1552
[89] N. Elkashef, R.S. Srinivasa, S. Major, S.C. Sabharwal, K.P. Muthe, Sputter depositon of gallium nitride films using a GaAs target, Thin Solid Films1998,333:9
[90] C.R. Kingsley, T.J. Whitaker, A.T.S. Wee et al.,Development of chem.ical beam epitaxy for the depositon of gallium nitride, Mater. Sci. Eng 1995, B29:78-82
[91] T. Sasaki, T. Matsuoka, Substrate-polarity dependence of metalorganic vapor phase epitaxy grown GaN on SiC, J. App. Phys 199864:4531
[92] H Ishikawa, S Kobayashi, Y Koide, S Yamasaki, S Nagai, J Umezaki, M Koike, M Murakami, Effects of surface treatments and metal work functions on electrical properties at p-GaN/metal interfaces. J. Appl. Phys., 1997, 81(3): 1315-1322
[93] F.M. Amanullah, K.J.Pratap, V. Hari babu, Compositonal analysis and depth profile studies on undoped and doped tin oxide films prepared by spray technique, Mater. Sci. Eng. B1998, 52:93
[94] T.J.Ghang, C.R.brundle, D.W. Rice, Interpretation of the X-ray photoemission spectra of cobalt oxides and cobalt oxide surfaces, Surf. Sci. 1979, 59:413
[95] R.Y. Korotkov, M.A. Reshchikov, B.W. Wessels, Physica B 273, 80 (1999)
[96] B.Monemar, Fundamental energy gap of GaN from photoluminescence excitations pectra [J]. Phys.Rev, 1974, B10: 676-681
[97] Y.G. Yang, H.L. Ma, C.S. Xue, et al., Preparation and structural properties for GaN films grown on Si (111) by annealing. Applied Surface Science, 2002, 193: 254-260
[98] B.S. Simpkins, L.M. Ericson, R.M. Stroud, K.A.Pettingrew, P.E. Pehrsson, J. Cryst. Growth 2006, 290: 115-120
[99] C.M.Balkas, R.F. Davis, Synthesis Routes and Characterization of High-purity, Single-phase Gallium Nitride Powders, J. Am. Ceram. Soc,1996, 79, 2309-12
[100] W.S. Jung, Reaction Intermediate(s) in the Conversion of b-gallium Oxide to Gallium Nitride Under a Flow of Ammonia, Mater. Lett, 2002, 57, 110-114
[101] T.Y. Kim, S.H Lee, Y.H Mo, et al. Growth of GaN nanowires on Si substrate using Ni catalyst in vertical chemical vapor deposition reactor. J. Crystal Growth, 2003, 257: 97-103