GaN欧姆接触及器件的研究
摘要
本硕士论文是基于国家科技部重点基础研究发展规划项目(973项目)子课题“硅基宽带隙异质结构材料生长及器件研究” (2000年10月-2005年9月，No. G20000683-06)和国家自然科学基金(No. 60046001)的一部分研究工作。
近年来，宽禁带半导体材料GaN由于其在短波长发光器件、光探测器件以及抗辐射、高频和大功率电子器件方面的广阔应用前景而备受关注，发展十分迅速。由于GaN体单晶难以制备，生长高质量的薄膜单晶材料是研究开发GaN基器件的基本前提条件，同时器件的发展对电极的制备提出了更高的要求，因而研究金属电极与GaN的接触成为必然。
本论文系统分析了国内外GaN材料制备和器件应用的研究历史和现状，重点对硅基GaN薄膜材料和相关器件进行了研究。本文的主要工作是对金属与n型GaN的欧姆接触进行了研究，并在此基础上制备了硅基GaN上的紫外探测器和GaN肖特基二极管。
主要工作如下：
1、研究了Al单层及Ti／Al双层电极与n型Si基GaN和Al_2O_3基GaN在不同退火条件下的欧姆接触情况，并用X射线衍射谱(XRD)，二次离子质谱(SIMS)对界面固相反应进行了分析。获得了比较低的欧姆接触率，并建立和完善了一套关于欧姆接触率测试的系统。
2、在GaN上实现了MSM结构的光导型紫外光探测器，并初步研究了其性能。并制成基于GaN的肖特基二极管，对其进行了初步研究。
This work was supported by the State Science and Technology Ministry of the P. R. China under the contact No.G20000683-06,and by the National Natural Science Foundation of P. R. China under grant No. 60046001.
Recently,Gallium Nitride (GaN) as a wide band gap semiconductor has attracted more and more attention and advanced rapidly,mainly due to its promising applications in short-wave light-emitting devices,photodetectors,as well as anti-radiation,high frequency and high power electronic devices. Up to date,it is still very hard to grow GaN bulk crystals,so the heteroepitaxial growth of high quality GaN thin films is the premise for the development of GaN-based devices. At the same time,the rapid progress on devices requires better ohmic contact between metals and GaN,so much more research work must be carried out at once.
In this thesis,we presented a total review of the research history and current
status of GaN material and tbp devices. The primary investigation of this paper is the
ohmic contact between metafs'and GaN. Moreover,we have prepared photodetectors
and Schottky diodes based on GaN.
The main work in this thesis includes two contents as follow:
1 We have investigated the properties of ohmic contact between metal electrode (Al and Ti/Al electrode) and n-GaN dealed under different annealing conditions. By using XRD SIMS analytic methods and I-V measuremnet,we analysed the interface between metals and GaN,and suggested that it is effect to decrease the value of the ohmic contact. And we have built a system for testing the ohmic contact between metals and semiconductor materials.
2 We prepared photodetectors based on GaN/Si and GaN/ Al2O3 and Schottky diodes on GaN/Al2O3. Some basic research about these devices has been done.
近年来，宽禁带半导体材料GaN由于其在短波长发光器件、光探测器件以及抗辐射、高频和大功率电子器件方面的广阔应用前景而备受关注，发展十分迅速。由于GaN体单晶难以制备，生长高质量的薄膜单晶材料是研究开发GaN基器件的基本前提条件，同时器件的发展对电极的制备提出了更高的要求，因而研究金属电极与GaN的接触成为必然。
本论文系统分析了国内外GaN材料制备和器件应用的研究历史和现状，重点对硅基GaN薄膜材料和相关器件进行了研究。本文的主要工作是对金属与n型GaN的欧姆接触进行了研究，并在此基础上制备了硅基GaN上的紫外探测器和GaN肖特基二极管。
主要工作如下：
1、研究了Al单层及Ti／Al双层电极与n型Si基GaN和Al_2O_3基GaN在不同退火条件下的欧姆接触情况，并用X射线衍射谱(XRD)，二次离子质谱(SIMS)对界面固相反应进行了分析。获得了比较低的欧姆接触率，并建立和完善了一套关于欧姆接触率测试的系统。
2、在GaN上实现了MSM结构的光导型紫外光探测器，并初步研究了其性能。并制成基于GaN的肖特基二极管，对其进行了初步研究。
This work was supported by the State Science and Technology Ministry of the P. R. China under the contact No.G20000683-06,and by the National Natural Science Foundation of P. R. China under grant No. 60046001.
Recently,Gallium Nitride (GaN) as a wide band gap semiconductor has attracted more and more attention and advanced rapidly,mainly due to its promising applications in short-wave light-emitting devices,photodetectors,as well as anti-radiation,high frequency and high power electronic devices. Up to date,it is still very hard to grow GaN bulk crystals,so the heteroepitaxial growth of high quality GaN thin films is the premise for the development of GaN-based devices. At the same time,the rapid progress on devices requires better ohmic contact between metals and GaN,so much more research work must be carried out at once.
In this thesis,we presented a total review of the research history and current
status of GaN material and tbp devices. The primary investigation of this paper is the
ohmic contact between metafs'and GaN. Moreover,we have prepared photodetectors
and Schottky diodes based on GaN.
The main work in this thesis includes two contents as follow:
1 We have investigated the properties of ohmic contact between metal electrode (Al and Ti/Al electrode) and n-GaN dealed under different annealing conditions. By using XRD SIMS analytic methods and I-V measuremnet,we analysed the interface between metals and GaN,and suggested that it is effect to decrease the value of the ohmic contact. And we have built a system for testing the ohmic contact between metals and semiconductor materials.
2 We prepared photodetectors based on GaN/Si and GaN/ Al2O3 and Schottky diodes on GaN/Al2O3. Some basic research about these devices has been done.
引文
[1] B.Daudin, J. L. Rouviere, M. Arlery, Appl. Phys. Lett. 1996, 69:2480
[2] Bykhovski A. D., Kaminski M.S., Shur V.V., Chen Q.C., Khan M.A, Appl.Phys. Lett. 1996, 69:3254
[3] R. B. Zetterstorm, J. Mater. Sci. 1970, 5:1102
[4] E. Eider, J. Cryst. Growth, 1974, 22:44
[5] Y. A. Vodakov, M. I. Karklina, E. N. Mokhov, A. D. Roenkov, Inorg. Mater. 1980, 17:537
[6] Porowski, M. Bockowski, B. Lucznik, M. Wroblewski, S. Krukowski, I. Grzegory, M. Leszczynski, G. Nowak, K. Pakula, J. M. Baranowski, Mater. Res. Soc. Symp. Proc. 1997, 449:35
[7] Y. Melnik, A. Nikolaev, I. Nikitina, K. Vassilevski ,V. Dmitriev, Mater. Res. Soc. Symp. Proc. 1998, 482:269
[8] S.Nakamura and G.Fasol, SpringerVerlag, Berlin, 1997
[9] S.P.Denbaars, S.Keller, Semicond. Semimet., 1997, 50:11
[10] S.Nakamura, Jpn.J.Appl.Phys, 1991,30:1705
[11] 彭英才等．半导体学报，1997，7：24
[12] C Y Myung et al. J. Cryst. Growth, 1997, 175/176:139
[13] M.E.Lin, B.Sverdlov, G.L.Zhou et al., Appl. Phys. Lett., 1993, 62:3479
[14] T.D. Moustaka, R.J.Molnar, Mater. Res. Soc. Conf. Proc., 1993, 281:753
[15] F.Nobuhiko, Y.Nasaki, K.Kouichi et al., J.Cryst. Growth, 1998, 189/190:385
[16] H.P. Maruska, J.J.Tietjen, Appl.Phys. Lett. 1969, 15:327
[17] S. Nakamura, T. Mukai, M. Senoh, J. Appl. Phys., 1992, 71:554
[18] T. L. Chu, K. Ito, R. K. Smeltzer, S. S. C. Chu, J. Electrochem. Soc. 1974, 121:159
[19] M. llegems, R. Dingle, J. Appl. Phys. 1973,44: 4234.
[20] S. Nakamura, M. Senoh, S.Nagahama, N.Iwasa, T.Yamada, T.Matsushita, H.Kiyoku, Y.Sugimoto, T.Kozaki, H.Umemoto, K.Chocho, Appl. Phys. Lett. 1998, 72: 2014.
[21] O. H.Nam, M.D.Bermser, T.S.Zheleva, R. F. Davis, Appl. Phys. Lett. 1997, 71:2638
[22] T. S.Zheleva, O.H.Ham, M.D.Bremser, R.F.Davis, ibid. 1997, 71:2472
[23] Gehrke T. J., Electron. Mater. 2000, 29:306
[24] S.Y oshida, S.Misawa, S.Gonda, Appl. Phys. Lett., 1983, 42:427
[25] H. Amano, N. Sawaki, I. Akasaki, Y. Toyoda, Appl. Phys. Lett., 1986, 48:353
[26] T. Takeuchi, H. Amano, K. Hiramatsu, N. Sawaki, and I. Akasaki, J. Cryst. Growth, 115 (1991) 634
[27] T. Lei and T. D. Moustakas, J. Appl. Phys., 1992, 71:4933
[28] Z. Sitar, M. J. Paisley, B. Yah, and R. F. Davis, Mater. Res. Soc. Symp. Proc. 1990, 162:537
[29] A. Watanabe, T. Takeuchi, K. Hirosawa, H. Amano, K. Hiramatsu, I. Akasaki, J. Cryst. Growth, 1993, 128:391
[30] L. Wang, X. Liu, Y. Zan, J. Wang, D. Wang, D. Lu, Z. Wang, Appl. Phys. Lett., 1998, 72:109
[31] P. Kung, A. Saxler, X. Zhang, D. Walker, T. C. Wang, I. Ferguson, M. Razeghi, Appl. Phys. Lett., 1995, 66:2958
[32] J. W. Yang, C. J. Sun, Q. Chen, M. Z. Anwar, M. S. Khan, S. A. Nikishin, G. A. Seryogin, A. V. Osinsky, L. Chernyak, H. Temkin, C. Hu, S. Mahajan, Appl. Phys. Lett., 1996, 69:3566
[33] W. L. Zhou, F. Namavar, P. C. Colter, M. Yoganathan, M. W. Leksono, J. I. Pankove, J. Mater. Res., 1999, 14:1171
[34] M. Iwaya, T. Takeuchi, S. Yamaguchi, C. Wetzel, H. Amano, I. Akasaki, Jpn. J. Appl. Phys. 1998, 37:L316
[35] J.Neugebauer, C.G.Van de Walle, Phys. Rev. 1994, B50:8067
[36] C.G. Van de Walle, Catherine Stampfl and J.Neugebauer, J.Cryst. Growth 1998, 189/190:505
[37] J.Neugebauer, C.G.Van de Walle, Proc. ICPS-22, World Scientific, Singapore 1995
[38] X.Zhang, P.Kung, A.Saxler, D.Walker and M.Rezeghi, J.Appl.Phys. 1996, 80:6544
[39] A.Saxler, P.Kung, X.Zhang, D.Walker, J.Solomon, M.Ahoujja, W.C.Mitchel, H.R.Vydyanath, M.Rezeghi, ICDS-19. Vols.258-263. p.1161, edited by G.Davies and M.H.Nazare, Materials Science Forum, Trans Tech Publications, Switzerland, 1998.
[40] W.Gotz, N.M.Johnson, C.Chen, H.Liu, C.Kuo and W.Imler, Appl.Phys. Lett. 1996, 68:3144
[41] H. Amano, M. Kito, K. Hiramatsu et al., Jpn. J. Appl. Phys., 1989, 28:2112
[42] S. Nakamura, T. Mukai, M. Senoh, N. Iwasa, Jpn. J. Appl. Phys., 1992, 31:139
[43] J. A. Vechten, J. D. Zook, R. D. Horning et al., Jpn. J. Appl. Phys., 1992, 31: 3662
[44] Khan M A, Kuznia J N, Olson D T et al. Appl.Phys.lett. 1992, 60:2917
[45] S.Nakamura, T.Mukai and M.Senoh, Appl.Phys. Lett, 1994, 64(13): 1687
[46] S.Nakamura, M.Senoh, N.Iwasa and Shin-ichi Nagahama, Jpn.J.Appl.Phys. 1995, 34:797
[2] Bykhovski A. D., Kaminski M.S., Shur V.V., Chen Q.C., Khan M.A, Appl.Phys. Lett. 1996, 69:3254
[3] R. B. Zetterstorm, J. Mater. Sci. 1970, 5:1102
[4] E. Eider, J. Cryst. Growth, 1974, 22:44
[5] Y. A. Vodakov, M. I. Karklina, E. N. Mokhov, A. D. Roenkov, Inorg. Mater. 1980, 17:537
[6] Porowski, M. Bockowski, B. Lucznik, M. Wroblewski, S. Krukowski, I. Grzegory, M. Leszczynski, G. Nowak, K. Pakula, J. M. Baranowski, Mater. Res. Soc. Symp. Proc. 1997, 449:35
[7] Y. Melnik, A. Nikolaev, I. Nikitina, K. Vassilevski ,V. Dmitriev, Mater. Res. Soc. Symp. Proc. 1998, 482:269
[8] S.Nakamura and G.Fasol, SpringerVerlag, Berlin, 1997
[9] S.P.Denbaars, S.Keller, Semicond. Semimet., 1997, 50:11
[10] S.Nakamura, Jpn.J.Appl.Phys, 1991,30:1705
[11] 彭英才等．半导体学报，1997，7：24
[12] C Y Myung et al. J. Cryst. Growth, 1997, 175/176:139
[13] M.E.Lin, B.Sverdlov, G.L.Zhou et al., Appl. Phys. Lett., 1993, 62:3479
[14] T.D. Moustaka, R.J.Molnar, Mater. Res. Soc. Conf. Proc., 1993, 281:753
[15] F.Nobuhiko, Y.Nasaki, K.Kouichi et al., J.Cryst. Growth, 1998, 189/190:385
[16] H.P. Maruska, J.J.Tietjen, Appl.Phys. Lett. 1969, 15:327
[17] S. Nakamura, T. Mukai, M. Senoh, J. Appl. Phys., 1992, 71:554
[18] T. L. Chu, K. Ito, R. K. Smeltzer, S. S. C. Chu, J. Electrochem. Soc. 1974, 121:159
[19] M. llegems, R. Dingle, J. Appl. Phys. 1973,44: 4234.
[20] S. Nakamura, M. Senoh, S.Nagahama, N.Iwasa, T.Yamada, T.Matsushita, H.Kiyoku, Y.Sugimoto, T.Kozaki, H.Umemoto, K.Chocho, Appl. Phys. Lett. 1998, 72: 2014.
[21] O. H.Nam, M.D.Bermser, T.S.Zheleva, R. F. Davis, Appl. Phys. Lett. 1997, 71:2638
[22] T. S.Zheleva, O.H.Ham, M.D.Bremser, R.F.Davis, ibid. 1997, 71:2472
[23] Gehrke T. J., Electron. Mater. 2000, 29:306
[24] S.Y oshida, S.Misawa, S.Gonda, Appl. Phys. Lett., 1983, 42:427
[25] H. Amano, N. Sawaki, I. Akasaki, Y. Toyoda, Appl. Phys. Lett., 1986, 48:353
[26] T. Takeuchi, H. Amano, K. Hiramatsu, N. Sawaki, and I. Akasaki, J. Cryst. Growth, 115 (1991) 634
[27] T. Lei and T. D. Moustakas, J. Appl. Phys., 1992, 71:4933
[28] Z. Sitar, M. J. Paisley, B. Yah, and R. F. Davis, Mater. Res. Soc. Symp. Proc. 1990, 162:537
[29] A. Watanabe, T. Takeuchi, K. Hirosawa, H. Amano, K. Hiramatsu, I. Akasaki, J. Cryst. Growth, 1993, 128:391
[30] L. Wang, X. Liu, Y. Zan, J. Wang, D. Wang, D. Lu, Z. Wang, Appl. Phys. Lett., 1998, 72:109
[31] P. Kung, A. Saxler, X. Zhang, D. Walker, T. C. Wang, I. Ferguson, M. Razeghi, Appl. Phys. Lett., 1995, 66:2958
[32] J. W. Yang, C. J. Sun, Q. Chen, M. Z. Anwar, M. S. Khan, S. A. Nikishin, G. A. Seryogin, A. V. Osinsky, L. Chernyak, H. Temkin, C. Hu, S. Mahajan, Appl. Phys. Lett., 1996, 69:3566
[33] W. L. Zhou, F. Namavar, P. C. Colter, M. Yoganathan, M. W. Leksono, J. I. Pankove, J. Mater. Res., 1999, 14:1171
[34] M. Iwaya, T. Takeuchi, S. Yamaguchi, C. Wetzel, H. Amano, I. Akasaki, Jpn. J. Appl. Phys. 1998, 37:L316
[35] J.Neugebauer, C.G.Van de Walle, Phys. Rev. 1994, B50:8067
[36] C.G. Van de Walle, Catherine Stampfl and J.Neugebauer, J.Cryst. Growth 1998, 189/190:505
[37] J.Neugebauer, C.G.Van de Walle, Proc. ICPS-22, World Scientific, Singapore 1995
[38] X.Zhang, P.Kung, A.Saxler, D.Walker and M.Rezeghi, J.Appl.Phys. 1996, 80:6544
[39] A.Saxler, P.Kung, X.Zhang, D.Walker, J.Solomon, M.Ahoujja, W.C.Mitchel, H.R.Vydyanath, M.Rezeghi, ICDS-19. Vols.258-263. p.1161, edited by G.Davies and M.H.Nazare, Materials Science Forum, Trans Tech Publications, Switzerland, 1998.
[40] W.Gotz, N.M.Johnson, C.Chen, H.Liu, C.Kuo and W.Imler, Appl.Phys. Lett. 1996, 68:3144
[41] H. Amano, M. Kito, K. Hiramatsu et al., Jpn. J. Appl. Phys., 1989, 28:2112
[42] S. Nakamura, T. Mukai, M. Senoh, N. Iwasa, Jpn. J. Appl. Phys., 1992, 31:139
[43] J. A. Vechten, J. D. Zook, R. D. Horning et al., Jpn. J. Appl. Phys., 1992, 31: 3662
[44] Khan M A, Kuznia J N, Olson D T et al. Appl.Phys.lett. 1992, 60:2917
[45] S.Nakamura, T.Mukai and M.Senoh, Appl.Phys. Lett, 1994, 64(13): 1687
[46] S.Nakamura, M.Senoh, N.Iwasa and Shin-ichi Nagahama, Jpn.J.Appl.Phys. 1995, 34:797