高Al组份AlGaN/GaN半导体材料的生长方法研究
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摘要
GaN基LED技术是实现半导体照明的关键技术,GaN基深紫外LED不仅具有高的白光转化效率,而且还在医疗、净化等方面有重要的应用。然而制备深紫外LED所需的高Al组份AlGaN材料的生长、掺杂一直是限制器件发展的关键因素。
本文在此背景下展开了对GaN基深紫外LED的研究工作,主要涉及AlN、高Al组份AlGaN材料的生长,AlGaN材料的n型和p型掺杂及UV LED器件研制等多方面,主要研究成果如下：
1、成功得到了氮化物半导体材料生长的最佳缓冲层厚度值,发现过厚或过薄的低温AlN缓冲层都不利于氮化物半导体材料的生长。
在自主MOCVD系统上,脉冲生长实现了高质量的AlN材料,其XRD (002)面的半高宽最小只有43arcsec,(102)面半高宽最小为228arcsec。
通过对AlN基板上不同Al组份的AlGaN材料生长,得到不同Al组份AlGaN材料生长时的应力变化关系。发现当其所受的张应力和压应力处于一种平衡的状态时,AlGaN材料有最佳的材料质量。
2、通过AlGaN/AIN超晶格结构(SLs)提高了AlGaN材料的生长质量。发现Al0.45Ga0.55N/AlN SLs的周期厚度对Al0.45Ga0.55N材料质量有重要影响,SLs结构不仅可以阻挡位错在薄膜生长时的延伸,而且可调控薄膜中的应力；研究得到最优的SLs层厚度为7nm,并生长出了高质量的Al0.45Ga0.55N材料,其(002)面XRD摇摆曲线的FWHM值仅为259arcsec,(102)面也只有885arcsec; AFM测得其表面有明显的原子台阶,粗糙度仅为0.185nm。
成功得到AlGaN材料生长时的Al组份与TMA/(TMA+TEG)的关系；发现AlGaN材料的表面粗糙度随Al组份的增加而增大；得到高质量的不同Al组份的AlGaN材料,其表面均有明显原子台阶。
3、实现了AlGaN材料的n型和p型有效掺杂。研究了Al组份对于AlGaN材料n型掺杂的影响,研究了SiH4掺入量与n型载流子浓度的变化关系,得到精确控制AlGaN材料的n型掺杂的工艺条件。
通过对生长温度、Mg源掺入量及退火温度的优化,实现了AlGaN材料的p型高质量掺杂,得到p型掺杂的Al组份为0.2的AlGaN材料的电阻率值仅为0.71Ω·cm,为此Al组份值AlGaN体材料p型掺杂。
采用AlGaN/GaN超晶格结构实现p型的高浓度掺杂,经过对超晶格周期厚度的优化,发现10nm的周期为Mg:AlGaN/GaN超晶格结构p型掺杂的最佳厚度值,得到了p型材料电阻率仅为0.034Ω·cm,p型载流子浓度高达1.26×1019cm-3,这一结果比通常体材料的掺杂水平高近一个数量级。
4、在蓝宝石衬底上成功生长出不同发光波长的AIXGa1-XN/AlYGa1-YN多量子阱(MQWs)。研究了AlxGa1-xN/AlYGa1-YN量子阱的周期厚度及势垒Si掺杂对MQWs发光特性的影响,
成功生长出高质量的、波长小于300nm的UV LED全结构。采用横向结构、通过器件工艺的流片,成功获得UV LED管芯。对器件的测试结果显示,UV LED的输出功率达到毫瓦量级。
5、经过对生长条件的优化,有效地提高了GaN材料的生长质量。其(002)面的半高宽由最初的800arcsec减小到378arcsec,(102)的半高宽也有1508arcsec减小到了597arcsec。
得到了脉冲法生长的高质量A1N为基板得到高质量的GaN材料,生长的材料表面原子台阶明显,XRD测得的(102)面半高宽降至348arcsec,(002)面半高宽更是低至70arcsec,为目前已报道的蓝宝石衬底上生长GaN的最小半高宽。
6、在蓝宝石衬底成功生长出AlInN/GaN异质结材料,采用脉冲法有效提高了AlInN薄膜的生长质量,并通过对TMA流量及A1N插入层厚度的优化提高了AlInN/GaN异质结的电学特性,报道的异质结迁移率可达1033cm2/vs,2DEG面密度达1.96E+13/cm2。
7、采用多超晶格结构有效提高了r面蓝宝石衬底上的非极性a-GaN材料的生长质量。研究表明多超晶格结构可有效提高a-GaN材料的质量,消除表面的三角坑缺陷。报道了高质量的a-GaN材料,其摇摆曲线FWHM仅为695arcseco
综上所述,本文通过对生长深紫外LED所需的各关键技术的研究,得到了高质量的AlN、AlGaN材料及实现了n型、p型AlGaN材料的有效掺杂,制备出了不同发光波长的量子阱结构,外延生长了深紫外LED的全结构,得到毫瓦级功率的UV LED器件。同时,外延生长出了高质量的GaN材料、AlInN/GaN异质结材料及a面GaN材料。
The technology of GaN-based LED is the key to semiconductor lighting, GaN-based deep UV LED not only has high conversion efficiency to white light, but also has wide use in medical, cleaning, and other important applications. However, obtaining high-quality materials and high doping levels are difficult for AlGaN films with high Al fraction, and limit the development of devices.
In the dissertation, the GaN-based UV LED is studied, the major work is focus on the growth of AlN, AlGaN with high Al fraction, doping of n-type and p-type AlGaN films and fabrication of UV LED devices. The major achievements are listed.
1. The best thickness of LT-AlN buffer layer is obtained. It is found that too thick or too thin buffer layer is damaged to the growth of nitride semiconductor materials.
The method of pulse MOCVD is used in growth high-quality AlN films. The FWHM of rocking curve of AlN (002) plane is only43arcsec, and that of(102) plane is only228arcsec, the materials quality has reached international advanced level.
Through the growth of AlGaN films with different Al fraction based on AlN templates, the relation between strain and Al fraction is found. We also found that when the tensile strain and compress strain is in balance, the materials have high qualities.
2. The quality of AlGaN films is improving by using AlGaN/AIN superlattices. The thickness of AlGaN/AlN SLs has important effect on the quality of AlGaN films. The SLs structure can not only stop the extending of dislocations, but also can control the strain of the films. The best thickness of SLs is7nm. The high-quality AlGaN film is obtained, which have259arcsec FWHM of (002) plane and885arcsec FWHM of (102) plane, the RMS of AlGaN film is only0.185nm.
The relation between Al fraction of AlGaN and the ration of TMA/(TMA+TEG) is found in the work. We also find that the RMS of AlGaN films increase with increasing the Al fraction. The high-quality AlGaN films with different Al fraction are obtained, all the films have smooth surfaces.
3. The n-type and p-type AlGaN films are successfully doping. The effect of Al fraction on the n-type doping and the change of n-type carriers concentration with SiH4flow rate are studied. The conditions for accurately controlling of the n-type doped level are obtained.
The high level doping of p-type AlGaN is successfully achieved. Through optimization of the growth temperature, Mg flow rate and annealing temperature, the p-type AlGaN film with resistivity of0.71Q·cm is obtained, which is the optimal results for AlGaN films with0.2Al fraction.
Using AlGaN/GaN SLs structure, we achieve high concentrations of p-type doping. Through optimization of SL thickness, we find10nm is the best thickness for p-type doping of SL structure. The resistance of p-type material is only0.034Q·cm, and the p-type carrier concentration is as high as1.26×1019cm-3, The doping level of SLs structure is high than the usual structure.
4. AlxGa1-xN/AlYGa1-YN MQWs with different lighting wavelengths are successfully achieved. The effect of thickness of MQW and Si-doping of barrier on the luminescence properties of MQWs is studied.
High quality UV LED with wavelength less than300nm is successfully grown. UV LED chips with transverse structure are successful fabricated. The testing results show that the output power of UV LED is a few milliwatts.
5. Through optimization of growth conditions, the quality of GaN materials is effectively improved, the FWHM of (002) plane decreases from800arcsec to378arcsec, the FWHM of (102) decreases from1508arcsec to597arcsec.
High-quality GaN materials are grown on high-quality AlN template, the surface of GaN is smooth. FWHM of GaN (102) plane is reduced to348arcsec, and that of (102) plane is reduced to70arcsec, which is the best results as far as we know.
6. AlInN/GaN heterojunction materials are successfully grown on sapphire substrate. Pulse MOCVD method improves the AlInN film growth quality effectively, By optimization of the TMA flow rate and thickness of AlN, the mobility and2DEG density of AlInN/GaN heteroj unction are up to1033cm2/vs and1.96E+13/cm2respectively, which is close to the international research level.
7. The quality of a-GaN grown on r-sapphire substrate is improved by using several superlattice. The study shows that the superlattice can eliminate the triangular defects. High-quality of a-GaN material is achieved, the value of FWHM is only695arcsec, which is in the international advanced level.
In summary, this dissertation succeed in solving some key technical issues for the growth of deep UV LED, the issues include growth of high-quality AlN, AlGaN, doping of n-type and p-type AlGaN materials, growth of MQWs with different lighting wavelength and deep UV LED, fabrication of UV LED devices. Meanwhile, high quality of GaN materials, AlInN/GaN heteroj unction and a-GaN have been successfully obtained.
本文在此背景下展开了对GaN基深紫外LED的研究工作,主要涉及AlN、高Al组份AlGaN材料的生长,AlGaN材料的n型和p型掺杂及UV LED器件研制等多方面,主要研究成果如下：
1、成功得到了氮化物半导体材料生长的最佳缓冲层厚度值,发现过厚或过薄的低温AlN缓冲层都不利于氮化物半导体材料的生长。
在自主MOCVD系统上,脉冲生长实现了高质量的AlN材料,其XRD (002)面的半高宽最小只有43arcsec,(102)面半高宽最小为228arcsec。
通过对AlN基板上不同Al组份的AlGaN材料生长,得到不同Al组份AlGaN材料生长时的应力变化关系。发现当其所受的张应力和压应力处于一种平衡的状态时,AlGaN材料有最佳的材料质量。
2、通过AlGaN/AIN超晶格结构(SLs)提高了AlGaN材料的生长质量。发现Al0.45Ga0.55N/AlN SLs的周期厚度对Al0.45Ga0.55N材料质量有重要影响,SLs结构不仅可以阻挡位错在薄膜生长时的延伸,而且可调控薄膜中的应力；研究得到最优的SLs层厚度为7nm,并生长出了高质量的Al0.45Ga0.55N材料,其(002)面XRD摇摆曲线的FWHM值仅为259arcsec,(102)面也只有885arcsec; AFM测得其表面有明显的原子台阶,粗糙度仅为0.185nm。
成功得到AlGaN材料生长时的Al组份与TMA/(TMA+TEG)的关系；发现AlGaN材料的表面粗糙度随Al组份的增加而增大；得到高质量的不同Al组份的AlGaN材料,其表面均有明显原子台阶。
3、实现了AlGaN材料的n型和p型有效掺杂。研究了Al组份对于AlGaN材料n型掺杂的影响,研究了SiH4掺入量与n型载流子浓度的变化关系,得到精确控制AlGaN材料的n型掺杂的工艺条件。
通过对生长温度、Mg源掺入量及退火温度的优化,实现了AlGaN材料的p型高质量掺杂,得到p型掺杂的Al组份为0.2的AlGaN材料的电阻率值仅为0.71Ω·cm,为此Al组份值AlGaN体材料p型掺杂。
采用AlGaN/GaN超晶格结构实现p型的高浓度掺杂,经过对超晶格周期厚度的优化,发现10nm的周期为Mg:AlGaN/GaN超晶格结构p型掺杂的最佳厚度值,得到了p型材料电阻率仅为0.034Ω·cm,p型载流子浓度高达1.26×1019cm-3,这一结果比通常体材料的掺杂水平高近一个数量级。
4、在蓝宝石衬底上成功生长出不同发光波长的AIXGa1-XN/AlYGa1-YN多量子阱(MQWs)。研究了AlxGa1-xN/AlYGa1-YN量子阱的周期厚度及势垒Si掺杂对MQWs发光特性的影响,
成功生长出高质量的、波长小于300nm的UV LED全结构。采用横向结构、通过器件工艺的流片,成功获得UV LED管芯。对器件的测试结果显示,UV LED的输出功率达到毫瓦量级。
5、经过对生长条件的优化,有效地提高了GaN材料的生长质量。其(002)面的半高宽由最初的800arcsec减小到378arcsec,(102)的半高宽也有1508arcsec减小到了597arcsec。
得到了脉冲法生长的高质量A1N为基板得到高质量的GaN材料,生长的材料表面原子台阶明显,XRD测得的(102)面半高宽降至348arcsec,(002)面半高宽更是低至70arcsec,为目前已报道的蓝宝石衬底上生长GaN的最小半高宽。
6、在蓝宝石衬底成功生长出AlInN/GaN异质结材料,采用脉冲法有效提高了AlInN薄膜的生长质量,并通过对TMA流量及A1N插入层厚度的优化提高了AlInN/GaN异质结的电学特性,报道的异质结迁移率可达1033cm2/vs,2DEG面密度达1.96E+13/cm2。
7、采用多超晶格结构有效提高了r面蓝宝石衬底上的非极性a-GaN材料的生长质量。研究表明多超晶格结构可有效提高a-GaN材料的质量,消除表面的三角坑缺陷。报道了高质量的a-GaN材料,其摇摆曲线FWHM仅为695arcseco
综上所述,本文通过对生长深紫外LED所需的各关键技术的研究,得到了高质量的AlN、AlGaN材料及实现了n型、p型AlGaN材料的有效掺杂,制备出了不同发光波长的量子阱结构,外延生长了深紫外LED的全结构,得到毫瓦级功率的UV LED器件。同时,外延生长出了高质量的GaN材料、AlInN/GaN异质结材料及a面GaN材料。
The technology of GaN-based LED is the key to semiconductor lighting, GaN-based deep UV LED not only has high conversion efficiency to white light, but also has wide use in medical, cleaning, and other important applications. However, obtaining high-quality materials and high doping levels are difficult for AlGaN films with high Al fraction, and limit the development of devices.
In the dissertation, the GaN-based UV LED is studied, the major work is focus on the growth of AlN, AlGaN with high Al fraction, doping of n-type and p-type AlGaN films and fabrication of UV LED devices. The major achievements are listed.
1. The best thickness of LT-AlN buffer layer is obtained. It is found that too thick or too thin buffer layer is damaged to the growth of nitride semiconductor materials.
The method of pulse MOCVD is used in growth high-quality AlN films. The FWHM of rocking curve of AlN (002) plane is only43arcsec, and that of(102) plane is only228arcsec, the materials quality has reached international advanced level.
Through the growth of AlGaN films with different Al fraction based on AlN templates, the relation between strain and Al fraction is found. We also found that when the tensile strain and compress strain is in balance, the materials have high qualities.
2. The quality of AlGaN films is improving by using AlGaN/AIN superlattices. The thickness of AlGaN/AlN SLs has important effect on the quality of AlGaN films. The SLs structure can not only stop the extending of dislocations, but also can control the strain of the films. The best thickness of SLs is7nm. The high-quality AlGaN film is obtained, which have259arcsec FWHM of (002) plane and885arcsec FWHM of (102) plane, the RMS of AlGaN film is only0.185nm.
The relation between Al fraction of AlGaN and the ration of TMA/(TMA+TEG) is found in the work. We also find that the RMS of AlGaN films increase with increasing the Al fraction. The high-quality AlGaN films with different Al fraction are obtained, all the films have smooth surfaces.
3. The n-type and p-type AlGaN films are successfully doping. The effect of Al fraction on the n-type doping and the change of n-type carriers concentration with SiH4flow rate are studied. The conditions for accurately controlling of the n-type doped level are obtained.
The high level doping of p-type AlGaN is successfully achieved. Through optimization of the growth temperature, Mg flow rate and annealing temperature, the p-type AlGaN film with resistivity of0.71Q·cm is obtained, which is the optimal results for AlGaN films with0.2Al fraction.
Using AlGaN/GaN SLs structure, we achieve high concentrations of p-type doping. Through optimization of SL thickness, we find10nm is the best thickness for p-type doping of SL structure. The resistance of p-type material is only0.034Q·cm, and the p-type carrier concentration is as high as1.26×1019cm-3, The doping level of SLs structure is high than the usual structure.
4. AlxGa1-xN/AlYGa1-YN MQWs with different lighting wavelengths are successfully achieved. The effect of thickness of MQW and Si-doping of barrier on the luminescence properties of MQWs is studied.
High quality UV LED with wavelength less than300nm is successfully grown. UV LED chips with transverse structure are successful fabricated. The testing results show that the output power of UV LED is a few milliwatts.
5. Through optimization of growth conditions, the quality of GaN materials is effectively improved, the FWHM of (002) plane decreases from800arcsec to378arcsec, the FWHM of (102) decreases from1508arcsec to597arcsec.
High-quality GaN materials are grown on high-quality AlN template, the surface of GaN is smooth. FWHM of GaN (102) plane is reduced to348arcsec, and that of (102) plane is reduced to70arcsec, which is the best results as far as we know.
6. AlInN/GaN heterojunction materials are successfully grown on sapphire substrate. Pulse MOCVD method improves the AlInN film growth quality effectively, By optimization of the TMA flow rate and thickness of AlN, the mobility and2DEG density of AlInN/GaN heteroj unction are up to1033cm2/vs and1.96E+13/cm2respectively, which is close to the international research level.
7. The quality of a-GaN grown on r-sapphire substrate is improved by using several superlattice. The study shows that the superlattice can eliminate the triangular defects. High-quality of a-GaN material is achieved, the value of FWHM is only695arcsec, which is in the international advanced level.
In summary, this dissertation succeed in solving some key technical issues for the growth of deep UV LED, the issues include growth of high-quality AlN, AlGaN, doping of n-type and p-type AlGaN materials, growth of MQWs with different lighting wavelength and deep UV LED, fabrication of UV LED devices. Meanwhile, high quality of GaN materials, AlInN/GaN heteroj unction and a-GaN have been successfully obtained.
引文
[1.1]H. Amano et al. Metalorganic vapor phase epitaxial growth of a high quality GaN film using an AlN buffer layer. Applied Physics Letters,1986,48:353.
[1.2]Nakamura.S, Mukai, High-quality InGaN films grown on GaN films. Jpn. J. Appl. Phys.1992,31:L1457.
[1.3]T. Lei, T.D. Moustakas, R.J. Graham, Y. He and S. J. Berkowitz, J. Appl. Phys. 1992,71:4933.
[1.4]H. Amano, I Akasaki. Novel aspects of the growth of nitrides by MOVPE. J. Phys:Condens. Matter.2001,13:6935.
[1.5]H. Amano, I Akasaki, et.al. Metalorganic vapor phase epitaxial growth of a high quality GaN film suing an AlN buffer layer. Appl. Phys. Lett.,1986,48:353.
[1.6]Nakamura S. Crystal growth method for gallium nitride-based compound semiconductor. US patent:5290393,1994.
[1.7]郝跃,周小伟,王阳元等.绿色微纳电子学.科学出版社,2010.
[1.8]Nakamura S J, Mukai T. Candela-class High-brightness InGaN/AlGaN Double-heterostrcture Blue-Light-Emitting Diodes. Appl Phys Lett, 1994,64(13):1687-1689.
[1.9]Nakamura S J, Mukai T. High-brightness InGaN/AlGaN Double-heterostrcture Blue-Green-Light-Emitting Diodes. J Appl Phys,1994,76(12):8189-8191.
[1.10]段猛,郝跃.GaN基蓝色LED的研究进展.西安电子科技大学学报.2003,30(01)：60.
[1.11]于占涛.半导体照明网.2009-6-15.
[1.12]J.Han, et.al. AlGaN/GaN quantum well ultraviolet light emitting diodes. Appl. Phys. Lett.1998,73:1688.
[1.13]Chitnis, M.Asif.Khan, et.al. High DC power 325nm emission deep UV LEDs over sapphire. Electronics Letters.2002,38(25):1709.
[1.14]W.H.Sun, M.Asif.Khan,et.al. Continuous Wave Milliwatt Power AlGaN Light Emitting Diodes at 280 nm. Jpn.J.Appl.Phys.2004,43.L1419.
[1.15]V.Adivarahan, M.Asif.Khan,et.al.250 nm AlGaN light-emitting diodes. Appl.Phys.Lett.2004,85(12):2175.
[1.16]Hideki Hirayama, et.al.226-273 nm AlGaN deep-ultraviolet light-emitting diodes fabricated on multilayer AlN buffers on sapphire. Phys.Sta.Sol.(c).2008, 5(9):2969.
[2.1]H.Manasevit. Single-crystal gallium arsenide on insulating substrate. Appl.Phys.Lett.1968,12:156-158.
[2.2]Y.Seki, K.Tanno,et al. Properties of epitaxial GaAs layers from a triethyl gallium and arsine system. J.Electronchem.Soc.1975,122:1108-1112.
[2.3]张进城,西安电子科技大学博士学位论文,2003.
[2.4]牛南辉,北京工业大学博士学位论文,2006.
[2.5]郝跃,彭军,杨银堂.碳化硅宽带隙半导体技术.科学出版社.2000.
[2.6]刘恩科,朱秉升,罗晋生等.半导体物理学.国防工业出版社.1994.
[2.7]Eriko Ohshima, et.al. Growth of 2-in-size bulk ZnO single crystals by the hydrothermal method. J.Crys. Growth.2004,260:166.
[2.8]赵有文,董志远等.升华法生长AlN体单晶初探.半导体学报.2006,27(07)：1241.
[2.9]Hiramatsu K, Itoh S, Amano H, et.al. Growth mechanism of GaN grown on sapphire with AlN buffer layer by MOVPE. J.Crystal Growth.1991,115:628.
[2.10]O Ambacher. Growth and applications of Group Ⅲ-Nitrides. J.Phys.D:Appl.Phys.1998.31:2653.
[2.11]许振嘉.半导体的检测与分析(第二版).2007,科学出版社.
[2.12]H.heinke,et.al. X-ray diffraction analysis of the defect structure in epitaxial GaN. Appl.phys.Lett.2000,77:2145.
[2.13]E.Niikura,et.al. Improvement of crystal quality of AlN and AlGaN epitaxial layers by controlling the strain with th AIN/GaN multi-buffer layer. J.Cryst.Growth.2007,298:345.
[3.1]H.Gao and W.D.nix. Annu.Rev.Mater.Sci.1999,29:173.
[3.2]M.Asif Khan,et.al. Ⅲ-Nitride UV Devices. Jp.J.Appl.Phys.2005,44(10):7191.
[3.3]S.Kamiyama, M,Sawaki,et.al.2001 J.Cryst.Growth 223 83.
[3.4]J. Han, K. E. Waldrip, S. R. Lee, J. J. Figiel, S. J. Hearne, G. A. Petersen and S. M. Myers.2001 Appl.Phys.Lett.78 83.
[3.5]A. D. Bykhovski, B. L. Gelmont and M. S. Shur.1997 J. Appl. Phys.81 6332.
[3.6]J. P. Zhang, H. M. Wang, M. E. Gaevski, C. Q. Chen, Q. Fareed, J. W. Yang, G. Simin and M. A. Khan.2002 Appl. Phys, Lett.80 3542.
[3.7]H. M. Wang, J. P. Zhang, C. Q. Chen, Q. Fareed, J. W. Yang and M. A. Khan.2002 Appl.Phys. Lett.81604.
[3.8]M. A. Khan, J. N. Kuznia, R. A. Skogman, D. T. Olson, M. Macmillan and W. J. Choyke.1992 Appl. Phys. Lett.61 2539.
[3.9]M. A. Khan, J. N. Kuznia, D. T. Olson, T. George and W. T. Pike..1993 Appl. Phys. Lett.63 3470.
[3.10]J. P. Zhang, M. A. Khan, W. H. Sun, H. M. Wang, C. Q. Chen, Q. Fareed, E. Kuokstis and J. W. Yang.2002 Appl. Phys. Lett.814392.
[3.11]P.Vennegues,B.Beaumont,et al, Appl.phys.Lett.2000,87,pp4175.
[3.12]K Myunghee,et.al. Low-temperature growth of high quality AlN films on carbon face 6H-SiC. Physica Status Solidi-Rapid Research Letetrs,2(1):13.
[3.13]E.Kenichi,et.al. High-temperature growth of thick AlN layers on sapphire (0001) substrates by solid source halide vapor-phase epitaxy.2008, J.Cryst.Growth.310(17):4016.
[3.14]H.Hirayama,et.al.222-282 nm AlGaN and InAlGaN-based deep-UV LEDs fabricated on high-quality AlN on sapphire.2009, Phys.Status Solidi A,1-7.
[3.15]B Ryan G, et.al. Growth characteristics of AlN on sapphire substrates by modified migration-enhanced epitaxy.2009.J.Cryst.Growth.31(10):2834.
[3.16]Ambacher.et al,1999,J.Phys.D:Appl.Phys.31:2653.
[3.17]Stephen J. Pearton.. GaN and Related Materials. Gorden and Breach Science Publishers,1997.
[4.1]L.Esaki,R.Ten. IBM J.Res.Develop.1970,14:61.
[4.2]虞丽生.半导体异质结物理.科学出版社.
[4.3]A D Bykhovski, B L Gelmont and M S Shur. Elastic strain relaxation and piezoeffect in GaN-AIN, GaN-AlGaN and GaN-InGaN superlattices. J.Appl.Phys.1997,81(9):6332.
[4.4]E.Feltin,et,al. Stress control in GaN grown on silicon (111) by metalorganic vapor phase epitaxy. Appl.Phys.Lett.2001.79(20):3230.
[4.5]许振嘉.半导体的检测与分析(第二版).2007,科学出版社.
[4.6]C.Touzi,F.Omnes,et,al. J.Crystal Growth.2005.279:31.
[4.7]D.B.Li,et,al. J.Crystal Growth.2007.298:372.
[5.1]S.Nakamura,et.al. Si-doped and Ge-doped GaN films growth with GaN buffer layers. Jpn.J.Phys.Part 1.1992.39(9A):2883.
[5.2]Y.Koide, H.Itoh,et,al. J.Electronchem.Soc.1986,133:1956.
[5.3]H.G.Lee, M.Gershenzon, B.L.Goldenberg. J.Elec.Mat.1991,20:621.
[5.4]M.D.McCluskey, et,al. Phys.Rev.Lett.1998,80:4008.
[5.5]M.D.Bremser,et,al. MRS Internet J.Nitride Semicond. Res.1996,1:8.
[5.6]Van Vechten J A, Zook J D, Horning R D, et al. Defeating compensation in wide gap semiconductors by growing in H that is removed by low temperature de-ionizing radiation. Jpn J Appl Phys,1992,31(11):3662.
[5.7]Reboredo F A, Pantelidesl S T. Novel defect complexes and their role in the p-type doping of GaN. Phys Rev Lett,1999,82(9):1889.
[5.8]Amano H, Kito M, Hiramatsu K, et al. P-type conduction in Mg-doped GaN treated with low-energy electron beam irradiation(LEEBI). Jpn J.Appl Phys, 1989,28(12):2112.
[5.9]Nakamura S, Mukai T, Senob M, et al. Thermal annealing effects on p-type Mg-doped GaN films Jpn J Appl Phys,1992,31(2):139.
[5.10]Neugehauer J, Van de Walle C G. Role of hydrogen and hydrogen complexes in doping of GaN. Matter Res Soe Symp Proc[C],1996,423:619.
[5.11]Youn D, Laehab M, Hao M, et al. Investigation on the p-type activationmechanism in Mg-doped GaN films grown by metalorganic chemicalvapor deposition. Jpn J Appl Phys,1999,38(2):631.
[5.12]Kim K, Harrison J G. Critical Mg doping on the blue-light emission inp-type GaN thin film grown by metal-organic chemical-vapordeposition. J Vac Sci Technol.2003, A21:134.
[5.13]Yamamoto T, Katayama-Yoshida H. Electronic strutures of p-type GaN codoped with Be or Mg as the acceptors and Si or O as the donor condopants. J Cryst Growth,1998,189:532.
[5.14]Ahn K S, Kim D J, Moon Y T. Rapid thermal annealing method of p-GaN thin film growth. J Vac Sci Technol,2001, B19(1):215.
[5.15]Waki I, Fujioka H, Oshima M. Doping Mg on UHCVD add Ni research. Appl Phys Lett,2001,78(4):2899.
[5.16]Zhang Xiaomin, Wang Yanjie, Yang Ziwen et al, Optimization and Analysis of Magnesium Doping in MOCVD Grown p-GaN, Chinese Journal of Semiconductors,2008.29:1475.
[5.17]Wang Lili, Zhang Shumin, Yang Hui, and Liang Junwu, Optical and electrical properties of GaN:Mg grown by MOCVD, Chinese Journal of Semiconductors, 2008,29:29.
[5.18]Hongbo Yu, Wlodek Strupinski, Serkan Butun, Ekmel Ozbay, Mg-doped AlGaN frown on an AIN/sapphire template by metalorganic chemical vapour deposition, Phys stat sol (a),2006,203:868.
[5.19]S R Jeon, Z Ren, G Cui, J Su, M Gherasimova, and J.Han, Investigation of Mg doping in high-Al content p-type AlxGal-xN (0.3 [5.20]Chris G. Van de Walle and Jorg Neugebauer, First-principles calculations for defects and impurities:Applications to Ⅲ-nitrides, J Appl Phys,2004,95:3852.
[5.21]Chris G. Van de Walle, C.Stampfl, J Neugebauer, M D McCluskey, N M Johnson, Doping of AlGaN alloys, J Nitride Semicond,1999, Res.4S1, G10.4..
[5.22]Zhou Xiaowei, Li Peixian, Xu Shengrui and Hao yue. Growth and electrical properties of high-quality Mg-doped p-type A10.2Ga0.8N films. Journal of Semiconductors.2009,30(4):043002-1.
[5.23]Schubert E F.Doping in III-V Semiconductors.Cambridge, United Kindom, Cambridge University Press,1993.123
[6.1]陈军峰.西安电子科技大学硕士学位论文.2006.
[6.2]X.H.Zhang,W.Ljum, S.J.Chua. Optical transitions in InGaN/GaN quantum weills:effects of piezoelectric field. J. Cryst. Growth.2004,268:521.
[6.3]Y.Y.Chung, Y.S.Lin, K.J.Ma, et al. Quantum-well-width dependencies of postgrowth thermal annealing effects of InGaN/GaN quantum well. J. Appl.Phys. 2003,93:9693.
[6.4]M.Stevens, A.Bell, et al. Effect of layer thickness on the electronstatic potential in InGaN quantum wells. Appl.Phys.Lett.2004,85:4651.
[6.5]T.Wang, H.Saeki, J.Bai, et al. Effect of silicon doping on the optical and transport properties of InGaN/GaN multiple-quantum-well structure. Appl.Phys.Lett.2000,76:1737.
[6.6]Y.Hoon, J.J.Song, et al. Influence of Si doping on characteristics of InGaN/GaN multiple quantum wells. Appl.Phys.Lett.1998.73:1128.
[6.7]M.Y.Ryu, P.W.Yu, et al. Effects of Si-doping in the barrier on the recombination dynamics In InGaN/GaN quantum wells. J.Appl.Phys.2001,89:634.
[7.1]郝跃,周小伟,王阳元等.绿色微纳电子学.科学出版社,2010.
[7.2]C.J.Tun, et al. Dislocation reduction in GaN with multiple MgxNy/GaN buffer layers by metal organic chemical vapor deposition. Appl. Phys. Lett.2007, 90:212109.
[7.3]H. Amano, N. Sawaki, I. Akasaki, and Y. Toyoda,.Metalorganic vapor phase epitaxial growth of a high quality GaN film using an AlN buffer layer.. Appl. Phys. Lett.48,353-355 (1986).
[7.4]许振嘉.半导体的检测与分析(第二版).2007,科学出版社.
[7.5]J.Chen, S.M.Zhang,et al. Effects of reactor pressure on GaN nucleation layers and subsequent GaN epilayers grown on sapphire substrate. J.Cryst.Growth.2003,254:348.
[7.6]周小伟,郝跃等,不同厚度未掺杂GaN薄膜的特性分析.电子器件,2005,28：262.
[7.7]Tasco. V, Campa A, et al. Investigation of different mechanisms of GaN growth induced on AlN and GaN nucleation layers. J.Appl. Phys.2009,105 (6):063510.
[7.8]Lin Chaotong, et al. Improved GaN film overgrown with a molybdenum nanoisland mask. Appl. Phys. Lett.2008,93:031906.
[7.9]Dong-Sing Wuu,et al. Defect reduction of laterally regrown GaN on GaN-patterned sapphire substrates. J.Cryst.Growth.2009,311:3063.
[7.10]J.C.Song, et al. Characteristics comparison between GaN epilayers grown on patterned and unpatterned sapphire substrate (0001).J.Cryst.Growth.2007, 308:321.
[7.11]S. Arulkumaran, T. Egawa, H. Ishikawa, and T. Jimbo, J. Vac. Sci. Technol.2003,21:888.
[7.12]Ambacher, B. Foutz, J. Smart, et al. J. Appl.Phys.2000,87:334.
[7.13]T. Palacios, S. Rajan, A. Chakraborty, S. Heikman, S. Keller, S. P,DenBaars, and U. K. Mishra, IEEE Trans. Electron Devices 2005,52:2117
[7.14]J. Kuzmik, IEEE Electron Device Lett.2001,22:510.
[7.15]S.M.Bedair, F.G.Mcintosh,et al. Growth and characterization of In-based nitride compounds. J.Cryst.Growth.1997,178:32.
[7.16]M.Gonschorek, J.F.Carlin, et al. Two-demensional electron gas density in AlxIn1-xN/GaN heterostructures(0.03≤X≤0.23).J.Appl.Phys.2008,103:093714.
[7.17]Masanobu Hiroki,Narihiko maeda, et al. Fabrication of an InAlN-AlGaN-AlN-GaN Heterostructure with a Flat Surface and High Electron Mobility.Appl.phys.Express 1,2008,111102.
[7.18]Xu shengrui, Zhou xiaowei,et al.Particular electrical quality of a-plane GaN films grown on r-plane sapphire by metal-organic chemical vapor deposition. Journal of Semiconductors,2009,11.
[7.19]Xu S R,Hao Y, Zhang J C, Zhou X W,et al. Improvements in a-plane GaN crystal quality by AIN/AlGaN superlattices layers, J.Cryst.Growth.2009,311:3622.
[7.20]颜建峰,张洁等.r面蓝宝石衬底上采用两步A1N缓冲层法外延生长a面GaN薄膜及应力研究.半导体学报.2007,28(10)：1562.
[7.21]吴超,谢自力等.M面GaN平面内结构和光学各向异性研究.物理学报.2008,57(11)：7190.
[7.22]J P Liu, J B Limb, et.al. Blue LED grown on freestanding (11-20) a-plane GaN substrate. Appl. Phys. Lett.2008,92:011123.
[7.23]Ni X, Fu Y,Moon Y T, et al. Optimization of (1120) a-GaN growth by MOCVD on (1102) r-sapphire. J.Cryst Growth,2006,290:166.
[7.24]Li D S,Chen H, Yu H B, et al. Effects of carrier gas on the stress of a-GaN films grown on r-sapphire substrates by metalorganic chemical vapor deposition. J Cryst Growth,2004,263:76.
[7.25]颜建峰等,r面蓝宝石衬底上采用两步AlN缓冲层法外延生长a-GaN薄膜及应力研究.半导体学报.2007,28(10)：1562.
[1.2]Nakamura.S, Mukai, High-quality InGaN films grown on GaN films. Jpn. J. Appl. Phys.1992,31:L1457.
[1.3]T. Lei, T.D. Moustakas, R.J. Graham, Y. He and S. J. Berkowitz, J. Appl. Phys. 1992,71:4933.
[1.4]H. Amano, I Akasaki. Novel aspects of the growth of nitrides by MOVPE. J. Phys:Condens. Matter.2001,13:6935.
[1.5]H. Amano, I Akasaki, et.al. Metalorganic vapor phase epitaxial growth of a high quality GaN film suing an AlN buffer layer. Appl. Phys. Lett.,1986,48:353.
[1.6]Nakamura S. Crystal growth method for gallium nitride-based compound semiconductor. US patent:5290393,1994.
[1.7]郝跃,周小伟,王阳元等.绿色微纳电子学.科学出版社,2010.
[1.8]Nakamura S J, Mukai T. Candela-class High-brightness InGaN/AlGaN Double-heterostrcture Blue-Light-Emitting Diodes. Appl Phys Lett, 1994,64(13):1687-1689.
[1.9]Nakamura S J, Mukai T. High-brightness InGaN/AlGaN Double-heterostrcture Blue-Green-Light-Emitting Diodes. J Appl Phys,1994,76(12):8189-8191.
[1.10]段猛,郝跃.GaN基蓝色LED的研究进展.西安电子科技大学学报.2003,30(01)：60.
[1.11]于占涛.半导体照明网.2009-6-15.
[1.12]J.Han, et.al. AlGaN/GaN quantum well ultraviolet light emitting diodes. Appl. Phys. Lett.1998,73:1688.
[1.13]Chitnis, M.Asif.Khan, et.al. High DC power 325nm emission deep UV LEDs over sapphire. Electronics Letters.2002,38(25):1709.
[1.14]W.H.Sun, M.Asif.Khan,et.al. Continuous Wave Milliwatt Power AlGaN Light Emitting Diodes at 280 nm. Jpn.J.Appl.Phys.2004,43.L1419.
[1.15]V.Adivarahan, M.Asif.Khan,et.al.250 nm AlGaN light-emitting diodes. Appl.Phys.Lett.2004,85(12):2175.
[1.16]Hideki Hirayama, et.al.226-273 nm AlGaN deep-ultraviolet light-emitting diodes fabricated on multilayer AlN buffers on sapphire. Phys.Sta.Sol.(c).2008, 5(9):2969.
[2.1]H.Manasevit. Single-crystal gallium arsenide on insulating substrate. Appl.Phys.Lett.1968,12:156-158.
[2.2]Y.Seki, K.Tanno,et al. Properties of epitaxial GaAs layers from a triethyl gallium and arsine system. J.Electronchem.Soc.1975,122:1108-1112.
[2.3]张进城,西安电子科技大学博士学位论文,2003.
[2.4]牛南辉,北京工业大学博士学位论文,2006.
[2.5]郝跃,彭军,杨银堂.碳化硅宽带隙半导体技术.科学出版社.2000.
[2.6]刘恩科,朱秉升,罗晋生等.半导体物理学.国防工业出版社.1994.
[2.7]Eriko Ohshima, et.al. Growth of 2-in-size bulk ZnO single crystals by the hydrothermal method. J.Crys. Growth.2004,260:166.
[2.8]赵有文,董志远等.升华法生长AlN体单晶初探.半导体学报.2006,27(07)：1241.
[2.9]Hiramatsu K, Itoh S, Amano H, et.al. Growth mechanism of GaN grown on sapphire with AlN buffer layer by MOVPE. J.Crystal Growth.1991,115:628.
[2.10]O Ambacher. Growth and applications of Group Ⅲ-Nitrides. J.Phys.D:Appl.Phys.1998.31:2653.
[2.11]许振嘉.半导体的检测与分析(第二版).2007,科学出版社.
[2.12]H.heinke,et.al. X-ray diffraction analysis of the defect structure in epitaxial GaN. Appl.phys.Lett.2000,77:2145.
[2.13]E.Niikura,et.al. Improvement of crystal quality of AlN and AlGaN epitaxial layers by controlling the strain with th AIN/GaN multi-buffer layer. J.Cryst.Growth.2007,298:345.
[3.1]H.Gao and W.D.nix. Annu.Rev.Mater.Sci.1999,29:173.
[3.2]M.Asif Khan,et.al. Ⅲ-Nitride UV Devices. Jp.J.Appl.Phys.2005,44(10):7191.
[3.3]S.Kamiyama, M,Sawaki,et.al.2001 J.Cryst.Growth 223 83.
[3.4]J. Han, K. E. Waldrip, S. R. Lee, J. J. Figiel, S. J. Hearne, G. A. Petersen and S. M. Myers.2001 Appl.Phys.Lett.78 83.
[3.5]A. D. Bykhovski, B. L. Gelmont and M. S. Shur.1997 J. Appl. Phys.81 6332.
[3.6]J. P. Zhang, H. M. Wang, M. E. Gaevski, C. Q. Chen, Q. Fareed, J. W. Yang, G. Simin and M. A. Khan.2002 Appl. Phys, Lett.80 3542.
[3.7]H. M. Wang, J. P. Zhang, C. Q. Chen, Q. Fareed, J. W. Yang and M. A. Khan.2002 Appl.Phys. Lett.81604.
[3.8]M. A. Khan, J. N. Kuznia, R. A. Skogman, D. T. Olson, M. Macmillan and W. J. Choyke.1992 Appl. Phys. Lett.61 2539.
[3.9]M. A. Khan, J. N. Kuznia, D. T. Olson, T. George and W. T. Pike..1993 Appl. Phys. Lett.63 3470.
[3.10]J. P. Zhang, M. A. Khan, W. H. Sun, H. M. Wang, C. Q. Chen, Q. Fareed, E. Kuokstis and J. W. Yang.2002 Appl. Phys. Lett.814392.
[3.11]P.Vennegues,B.Beaumont,et al, Appl.phys.Lett.2000,87,pp4175.
[3.12]K Myunghee,et.al. Low-temperature growth of high quality AlN films on carbon face 6H-SiC. Physica Status Solidi-Rapid Research Letetrs,2(1):13.
[3.13]E.Kenichi,et.al. High-temperature growth of thick AlN layers on sapphire (0001) substrates by solid source halide vapor-phase epitaxy.2008, J.Cryst.Growth.310(17):4016.
[3.14]H.Hirayama,et.al.222-282 nm AlGaN and InAlGaN-based deep-UV LEDs fabricated on high-quality AlN on sapphire.2009, Phys.Status Solidi A,1-7.
[3.15]B Ryan G, et.al. Growth characteristics of AlN on sapphire substrates by modified migration-enhanced epitaxy.2009.J.Cryst.Growth.31(10):2834.
[3.16]Ambacher.et al,1999,J.Phys.D:Appl.Phys.31:2653.
[3.17]Stephen J. Pearton.. GaN and Related Materials. Gorden and Breach Science Publishers,1997.
[4.1]L.Esaki,R.Ten. IBM J.Res.Develop.1970,14:61.
[4.2]虞丽生.半导体异质结物理.科学出版社.
[4.3]A D Bykhovski, B L Gelmont and M S Shur. Elastic strain relaxation and piezoeffect in GaN-AIN, GaN-AlGaN and GaN-InGaN superlattices. J.Appl.Phys.1997,81(9):6332.
[4.4]E.Feltin,et,al. Stress control in GaN grown on silicon (111) by metalorganic vapor phase epitaxy. Appl.Phys.Lett.2001.79(20):3230.
[4.5]许振嘉.半导体的检测与分析(第二版).2007,科学出版社.
[4.6]C.Touzi,F.Omnes,et,al. J.Crystal Growth.2005.279:31.
[4.7]D.B.Li,et,al. J.Crystal Growth.2007.298:372.
[5.1]S.Nakamura,et.al. Si-doped and Ge-doped GaN films growth with GaN buffer layers. Jpn.J.Phys.Part 1.1992.39(9A):2883.
[5.2]Y.Koide, H.Itoh,et,al. J.Electronchem.Soc.1986,133:1956.
[5.3]H.G.Lee, M.Gershenzon, B.L.Goldenberg. J.Elec.Mat.1991,20:621.
[5.4]M.D.McCluskey, et,al. Phys.Rev.Lett.1998,80:4008.
[5.5]M.D.Bremser,et,al. MRS Internet J.Nitride Semicond. Res.1996,1:8.
[5.6]Van Vechten J A, Zook J D, Horning R D, et al. Defeating compensation in wide gap semiconductors by growing in H that is removed by low temperature de-ionizing radiation. Jpn J Appl Phys,1992,31(11):3662.
[5.7]Reboredo F A, Pantelidesl S T. Novel defect complexes and their role in the p-type doping of GaN. Phys Rev Lett,1999,82(9):1889.
[5.8]Amano H, Kito M, Hiramatsu K, et al. P-type conduction in Mg-doped GaN treated with low-energy electron beam irradiation(LEEBI). Jpn J.Appl Phys, 1989,28(12):2112.
[5.9]Nakamura S, Mukai T, Senob M, et al. Thermal annealing effects on p-type Mg-doped GaN films Jpn J Appl Phys,1992,31(2):139.
[5.10]Neugehauer J, Van de Walle C G. Role of hydrogen and hydrogen complexes in doping of GaN. Matter Res Soe Symp Proc[C],1996,423:619.
[5.11]Youn D, Laehab M, Hao M, et al. Investigation on the p-type activationmechanism in Mg-doped GaN films grown by metalorganic chemicalvapor deposition. Jpn J Appl Phys,1999,38(2):631.
[5.12]Kim K, Harrison J G. Critical Mg doping on the blue-light emission inp-type GaN thin film grown by metal-organic chemical-vapordeposition. J Vac Sci Technol.2003, A21:134.
[5.13]Yamamoto T, Katayama-Yoshida H. Electronic strutures of p-type GaN codoped with Be or Mg as the acceptors and Si or O as the donor condopants. J Cryst Growth,1998,189:532.
[5.14]Ahn K S, Kim D J, Moon Y T. Rapid thermal annealing method of p-GaN thin film growth. J Vac Sci Technol,2001, B19(1):215.
[5.15]Waki I, Fujioka H, Oshima M. Doping Mg on UHCVD add Ni research. Appl Phys Lett,2001,78(4):2899.
[5.16]Zhang Xiaomin, Wang Yanjie, Yang Ziwen et al, Optimization and Analysis of Magnesium Doping in MOCVD Grown p-GaN, Chinese Journal of Semiconductors,2008.29:1475.
[5.17]Wang Lili, Zhang Shumin, Yang Hui, and Liang Junwu, Optical and electrical properties of GaN:Mg grown by MOCVD, Chinese Journal of Semiconductors, 2008,29:29.
[5.18]Hongbo Yu, Wlodek Strupinski, Serkan Butun, Ekmel Ozbay, Mg-doped AlGaN frown on an AIN/sapphire template by metalorganic chemical vapour deposition, Phys stat sol (a),2006,203:868.
[5.19]S R Jeon, Z Ren, G Cui, J Su, M Gherasimova, and J.Han, Investigation of Mg doping in high-Al content p-type AlxGal-xN (0.3
[5.21]Chris G. Van de Walle, C.Stampfl, J Neugebauer, M D McCluskey, N M Johnson, Doping of AlGaN alloys, J Nitride Semicond,1999, Res.4S1, G10.4..
[5.22]Zhou Xiaowei, Li Peixian, Xu Shengrui and Hao yue. Growth and electrical properties of high-quality Mg-doped p-type A10.2Ga0.8N films. Journal of Semiconductors.2009,30(4):043002-1.
[5.23]Schubert E F.Doping in III-V Semiconductors.Cambridge, United Kindom, Cambridge University Press,1993.123
[6.1]陈军峰.西安电子科技大学硕士学位论文.2006.
[6.2]X.H.Zhang,W.Ljum, S.J.Chua. Optical transitions in InGaN/GaN quantum weills:effects of piezoelectric field. J. Cryst. Growth.2004,268:521.
[6.3]Y.Y.Chung, Y.S.Lin, K.J.Ma, et al. Quantum-well-width dependencies of postgrowth thermal annealing effects of InGaN/GaN quantum well. J. Appl.Phys. 2003,93:9693.
[6.4]M.Stevens, A.Bell, et al. Effect of layer thickness on the electronstatic potential in InGaN quantum wells. Appl.Phys.Lett.2004,85:4651.
[6.5]T.Wang, H.Saeki, J.Bai, et al. Effect of silicon doping on the optical and transport properties of InGaN/GaN multiple-quantum-well structure. Appl.Phys.Lett.2000,76:1737.
[6.6]Y.Hoon, J.J.Song, et al. Influence of Si doping on characteristics of InGaN/GaN multiple quantum wells. Appl.Phys.Lett.1998.73:1128.
[6.7]M.Y.Ryu, P.W.Yu, et al. Effects of Si-doping in the barrier on the recombination dynamics In InGaN/GaN quantum wells. J.Appl.Phys.2001,89:634.
[7.1]郝跃,周小伟,王阳元等.绿色微纳电子学.科学出版社,2010.
[7.2]C.J.Tun, et al. Dislocation reduction in GaN with multiple MgxNy/GaN buffer layers by metal organic chemical vapor deposition. Appl. Phys. Lett.2007, 90:212109.
[7.3]H. Amano, N. Sawaki, I. Akasaki, and Y. Toyoda,.Metalorganic vapor phase epitaxial growth of a high quality GaN film using an AlN buffer layer.. Appl. Phys. Lett.48,353-355 (1986).
[7.4]许振嘉.半导体的检测与分析(第二版).2007,科学出版社.
[7.5]J.Chen, S.M.Zhang,et al. Effects of reactor pressure on GaN nucleation layers and subsequent GaN epilayers grown on sapphire substrate. J.Cryst.Growth.2003,254:348.
[7.6]周小伟,郝跃等,不同厚度未掺杂GaN薄膜的特性分析.电子器件,2005,28：262.
[7.7]Tasco. V, Campa A, et al. Investigation of different mechanisms of GaN growth induced on AlN and GaN nucleation layers. J.Appl. Phys.2009,105 (6):063510.
[7.8]Lin Chaotong, et al. Improved GaN film overgrown with a molybdenum nanoisland mask. Appl. Phys. Lett.2008,93:031906.
[7.9]Dong-Sing Wuu,et al. Defect reduction of laterally regrown GaN on GaN-patterned sapphire substrates. J.Cryst.Growth.2009,311:3063.
[7.10]J.C.Song, et al. Characteristics comparison between GaN epilayers grown on patterned and unpatterned sapphire substrate (0001).J.Cryst.Growth.2007, 308:321.
[7.11]S. Arulkumaran, T. Egawa, H. Ishikawa, and T. Jimbo, J. Vac. Sci. Technol.2003,21:888.
[7.12]Ambacher, B. Foutz, J. Smart, et al. J. Appl.Phys.2000,87:334.
[7.13]T. Palacios, S. Rajan, A. Chakraborty, S. Heikman, S. Keller, S. P,DenBaars, and U. K. Mishra, IEEE Trans. Electron Devices 2005,52:2117
[7.14]J. Kuzmik, IEEE Electron Device Lett.2001,22:510.
[7.15]S.M.Bedair, F.G.Mcintosh,et al. Growth and characterization of In-based nitride compounds. J.Cryst.Growth.1997,178:32.
[7.16]M.Gonschorek, J.F.Carlin, et al. Two-demensional electron gas density in AlxIn1-xN/GaN heterostructures(0.03≤X≤0.23).J.Appl.Phys.2008,103:093714.
[7.17]Masanobu Hiroki,Narihiko maeda, et al. Fabrication of an InAlN-AlGaN-AlN-GaN Heterostructure with a Flat Surface and High Electron Mobility.Appl.phys.Express 1,2008,111102.
[7.18]Xu shengrui, Zhou xiaowei,et al.Particular electrical quality of a-plane GaN films grown on r-plane sapphire by metal-organic chemical vapor deposition. Journal of Semiconductors,2009,11.
[7.19]Xu S R,Hao Y, Zhang J C, Zhou X W,et al. Improvements in a-plane GaN crystal quality by AIN/AlGaN superlattices layers, J.Cryst.Growth.2009,311:3622.
[7.20]颜建峰,张洁等.r面蓝宝石衬底上采用两步A1N缓冲层法外延生长a面GaN薄膜及应力研究.半导体学报.2007,28(10)：1562.
[7.21]吴超,谢自力等.M面GaN平面内结构和光学各向异性研究.物理学报.2008,57(11)：7190.
[7.22]J P Liu, J B Limb, et.al. Blue LED grown on freestanding (11-20) a-plane GaN substrate. Appl. Phys. Lett.2008,92:011123.
[7.23]Ni X, Fu Y,Moon Y T, et al. Optimization of (1120) a-GaN growth by MOCVD on (1102) r-sapphire. J.Cryst Growth,2006,290:166.
[7.24]Li D S,Chen H, Yu H B, et al. Effects of carrier gas on the stress of a-GaN films grown on r-sapphire substrates by metalorganic chemical vapor deposition. J Cryst Growth,2004,263:76.
[7.25]颜建峰等,r面蓝宝石衬底上采用两步AlN缓冲层法外延生长a-GaN薄膜及应力研究.半导体学报.2007,28(10)：1562.