摘要
ZnO由于大的禁带宽度(3.37eV)和室温下高的激子束缚能(60meV)而被认为做为紫外发光器件最有潜力的材料之一。CdO禁带宽度为2.3eV,它与ZnO形成的CdZnO合金半导体则是应用于可见发光的潜在材料。本文研究了硅基Zn0(CdZnO)薄膜的发光性质；在此基础上,制备了电致发光器件,对器件的电致发光性能进行了研究。本文得到的主要结果如下：
1.利用直流反应溅射法在Si衬底制备ZnO薄膜,研究了ZnO薄膜经不同条件的快速热处理后的光致发光。结果表明：经Ar气氛下800℃快速热处理后的ZnO薄膜比在O2气氛下800℃快速热处理的ZnO薄膜显示出更强的近带边发光。然而,后者再经过Ar气氛下低温60℃热处理后,其近带边发光强度则可与前者的相比拟。分析认为,ZnO薄膜经氧气氛下快速热处理后在其表面存在吸附的氧离子,它们对近带边光致发光不利。
2.以直流反应溅射法制备的ZnO薄膜做为半导体层,以射频反应溅射法制备的SiO2做为绝缘层,在重掺N型硅衬底上制备基于ZnO的金属-绝缘体-半导体(MIS)结构的发光器件。当SiO2厚度约为12nm时,器件在一定的正偏压下产生随机激射,而当SiO2厚度小于～9 nm时,器件仅产生自发辐射的电致发光。因此,只有当SiO2厚度足够厚时,高浓度的载流子才会限域在ZnO/Si02界面附近,从而为随机激射创造条件。
3.利用射频反应溅射制备CdZnO薄膜,研究热处理条件对薄膜晶体结构、表面形貌及光致发光的影响。研究发现：随着快速热处理温度的提高与时间的延长,CdZnO薄膜表面由于Cd的挥发加剧而形成更多的空洞,薄膜的近带边光致发光则发生蓝移。以CdZnO/Si02(MgO)/P+-Si为结构的器件在足够大的正向偏压下产生源于CdZnO带边辐射的电致发光。
With a wide direct band gap of 3.37 eV and large exaction binding energy of 60 meV at room temperature, ZnO is considered as one of the most promising materials for ultraviolet (UV) optoelectronics. The band gap of CdO is 2.3 eV. ZnO is expected to be the photolectric material in visible region when alloyed with CdO. In this paper the photoluminescence of silicon-based ZnO (CdZnO) films has been studied. Moreover, light-emitting devices were prepared and the electroluminescent of them has been investigated. The primary achievements are as follows.
1. ZnO films were deposited on the silicon subtract by direct current sputtering. The effect of RTA conditions on photoluminescence has been investigated. It is found that the ZnO film received the RTA at 800℃under Ar ambient shows much stronger PL than that received the RTA at 800℃under O2 ambient. With the post-RTA at 60℃under Ar ambient, the ZnO film received the RTA at 800℃under O2 ambient exhibits ultraviolet (UV) PL as intense as that of the ZnO film received the RTA at 800℃under Ar ambient. It is supposed that a certain amount of negatively charged oxygen species exist on the surface of the ZnO film received the RTA under O2 ambient, leading to a build-in electric field. This in turn reduces the recombination probability of photo-generated electrons and holes, resulting in the suppressed NBE PL.
2. With the ZnO and SiO2 acted as the semiconductor and insulator, the ZnO-MIS device was prepared on the n+-Si substrate by sputtering method. Under forward bias, the ZnO-MIS structure demonstrates random laser when the thickness of SiO2 is at-12 nm. With SiO2 thickness decreased to-9 nm, there is only spontaneous emission from ZnO-MIS structure. Only when the SiO2 is thick enough the random laser can be produced under forward bias with high concentration carriers accumulated in the Zn0/SiO2 interface.
3. The CdZnO films were deposited by radio frequency sputtering and the effect of RTA conditions on crystal structure, surface morphology and photoluminescence has been investigated. It is shown that with the increase of RTA temperature and RTA time, more voids are formed in the films due to the volatilization of Cd. In the meantime, the PL peak of CdZnO shows blue-shift. The CdZnO/SiO2 (MgO)/P+-Si structure was fabricated and the device exhibits the near-band-edge (NBE) emission from CdZnO.
引文
[I]D.C. Look. Recent advances in ZnO materials and devices. Materials Science and Engineering. 2001,B80,383-387.
[2]Anderson Janotti and Chris G Van de Walle. Fundamentals of zinc oxide as a semiconductor. Rep. Prog. Phys.,2009,72,126501.
[3]Kyu-Hyun Bang, Deuk-Kyu Hwang, Min-Chul Park, Young-Don Ko, Ilgu Yun and Jae-Min Myoung. Formation of p-type ZnO film on inP substrate by phosphor doping. Applied Surface Science,2003,210,177-182.
[4]Yongge Cao, Lei Miao, Sakae Tanemura, Masaki Tanemura, Yohei Kuno, and Yasuhiko Hayashi. Low resistivity p-ZnO films fabricated by sol-gel spin coating. Appl. Phys. Lett., 2006,88,251116.
[5]D.S. WIERSMA. The physics and applications of random lasers. Nature Physics 4,2008,359-367.
[6]Jinsub Park, Takenari Goto, Sung Hyun Park, Jun-seok Ha, Euijoon Yoon, and Takafumi Yao. Ultraviolet stimulated emission in periodically polarity-inverted ZnO structures at room temperature. Appl. Phys. Lett.,2010,97,171101.
[7]S.J. Peartona, D.P. Nortona, K. Ipa, Y.W. Heoa and T. Steinerb. Recent progress in processing and properties of ZnO. Prog. Mater. Sci.,2005,50,293-340.
[8]u. Ozgur, Ya. I. Alivov, C. Liu, A. Teke, M. A. Reshchikov, S. Dogan, V. Avrutin, S.-J. Cho, and H. Morkoc. A comprehensive review of ZnO materials and devices. J. Appl. Phys.,2005, 98,041301.
[9]A. Kobayashi, O. F. Sankey, and J. D. Dow, Deep energy levels of defects in the wurtzite semiconductors A IN, CdS, CdSe, ZnS, and ZnO, Phys. Rev. B,1983,28,946-956.
[10]A. Kobayashi, O. F. Sankey, S. M. Volz, and J. D. Dow, Semiempirical tight-binding band structures of wurtzite semiconductors:A1N, CdS, CdSe, ZnS, and ZnO, Phys. Rev. B,1983, 28,935-945.
[11]V. Assuncao, E. Fortunate A. Marques, H. Aguas, I. Ferreira, M.E.V. Costa, R. Martins. Influence of the deposition pressure on the properties of transparent and conductive ZnO.Ga thin-film produced by r.f. sputtering at room temperature. Thin Solid Films,2003, 427,401-405.
[12]V. Bhosle. A. Tiwari and J. Narayan. Electrical properties of transparent and conducting Ga doped ZnO. J. Appl. Phys.,2006,100,033713.
[13]K..Y. Cheong. Norani Muti, S.Roy Ramanan. Electrical and optical studies of ZnO:Ga thin films fabricated via the sol-gel technique. Thin Solid Films.2002,410,142-146.
[14]Jin-Hong Lee and Byung-Ok Park. Transparent conducting ZnO:Al, In and Sn thin films deposited by the sol-gel method. Thin Solid Films,2002,426,94-99.
[15]Z. L. Pei, C. Sun, M. H. Tan, J. Q. Xiao, D. H. Guan, R. F. Huang and L. S. Wen. Optical and electrical properties of direct-current magnetron sputtered ZnO:Al films. J. Appl. Phys..2001, 90,3432.
[16]Valentini, A., Quaranta, F., Rossi, M., Battaglin, G.. Preparation and characterization of Li doped ZnO films. J. Vacu. Sci.,1991,2,286-289.
[17]J. G. Lu, Y. Z. Zhang, Z. Z. Ye, Y. J. Zeng, H. P. He, L. P. Zhu, J. Y. Huang, L. Wang, J. Yuan, B. H. Zhao and X. H. Li. Control of p-and n-type conductivities in Li-doped ZnO thin films. Appl. Phys. Lett.,2006,89,112113.
[18]D. Zwingel and F. Gartner. Paramagnetic and optical properties of Na-doped ZnO single crystals. Solid State Communications,1974,14,45-49.
[19]G. W. Cong, W. Q. Peng, H. Y. Wei. X. X. Han and J. J. Wu et al. Comparison of valence band x-ray photoelectron spectrum between AI-N-codoped and N-doped ZnO films. Appl. Phys. Lett.,2006,88,062110.
[20]F. Zhuge, L. P. Zhu, Z. Z. Ye, D. W. Ma, J. G.Lu, J. Y. Huang, F. Z. Wang, Z. G. Ji and S. B. Zhang. ZnO p-n homojunctions and ohmic contacts to Al-N-co-doped p-type ZnO. Appl. Phys. Lett.,2005,87,092103.
[21]J. G. Lu, Y. Z. Zhang, Z. Z. Ye, L. P. Zhu, L. Wang, B. H. Zhao and Q. L. Liang. Low-resistivity, stable p-type ZnO thin films realized using a Li-N dual-acceptor doping method. Appl. Phys. Lett.,2006,88,222114.
[22]Zeng, Y. J., Ye, Z. Z., Xu, W. Z., Li, D. Y, Lu, J. G. Zhu, L. P. and Zhao, B. H. Dopant source choice for formation of p-type ZnO:Li acceptor. Appl. Phys. Lett.,2006,88,062107.
[23]Y. Lin a, J. Xie, H. Wang, Y. Li, C. Chavez, SangYeol Lee and S.R. Foltyn et al. Green luminescent zinc oxide films prepared by polymer-assisted deposition with rapid thermal process. Thin Solid Films.2005,492,101-104.
[24]Q. Zhao, X. Y. Xu, X. F. Song, X. Z. Zhang, and D. P. Yu. Enhanced field emission from ZnO nanorods via thermal annealing in oxygen. Appl. Phys. Lett.,2006,88,033102.
[25]Hong Seong Kang, Jeong Seok Kang, Jae Won Kim, and Sang Yeol Lee. Annealing effect on the property of ultraviolet and green emissions of ZnO thin films. J. Appl. Phys.,2004,95. 1246.
[26]Tae-Bong Hur, Gwang Soo Jeen, Yoon-Hwae Hwang and Hyung-Kook Kim. Photoluminescence of polycrystalline ZnO under different annealing conditions. J. Appl. Phys.,2003,94,5787.
[27]D. Wang, H. W. Seo, C.-C. Tin. M. J. Bozack, J. R. Williams and M. Park. Effects of postgrowth annealing treatment on the photoluminescence of zinc oxide nanorods. J. Appl. Phys.,2006,99.113509.
[28]Y. W. Heo. Origin of green luminescence in ZnO thin film grown by molecular-beam epitaxy. J. Appl. Phys.,2005,98,073502.
[29]Z.G. Wang, X.T. Zu, S. Zhu and L.M. Wang. Green luminescence originates from surface defects in ZnO nanoparticles. Physica E,2006,35,199-202.
[30]B. P. Zhang, N. T. Binh and Y. Segawa. Optical properties of ZnO rods formed by metalorganic chemical vapor deposition. Appl. Phys. Lett.,2003,83,1635.
[31]Jeong, Sang-Hun, Kim, Bong-Soo, Lee and Byung-Teak. Photoluminescence dependence of ZnO films grown on Si(100) by radio-frequency magnetron sputtering on the growth ambient. Appl. Phys. Lett.,2003,82,2625.
[32]Hang Ju Ko, Yefan Chen, Soon Ku Hong and Takafumi Yao. MBE growth of high-quality ZnO films on epi-GaN. J. Crys. Growth,2000,209,816.
[33]M.N. Kamalasanan and Subhas Chandra. Sol-gel synthesis of ZnO thin films. Thin Solid Films,1996,288,112-115.
[34]D.C. Look. Quantitative analysis of surface donors in ZnO. Surface Science,2007,601,5315.
[35]Eriko Ohshima, Hiraku Ogino, Ikuo Niikura, Katsumi Maeda, Mitsuru Sato, Masumi Ito and Tsuguo Fukuda. Growth of the 2-in-size bulk ZnO single crystals by the hydrothermal method. J. Crys. Growth,2004,260,166.
[36]T Sekiguchi, S Miyashita, K Obara, T Shishido and N Sakagami. Hydrothermal growth of ZnO single crystals and their optical characterization. J. Crys. Growth,2000,214,72-76.
[37]D.C. Look, D.C. Reynolds, J.R. Sizelove, R.L. Jones, C.W. Litton, G. Cantwell and W.C. Harsch. Electrical properties of bulk ZnO. Solid State Communications,1998,105,399.
[38]J Nause and B Nemeth. Pressurized melt growth of ZnO boules. Semiconductor science and technology,2005,20,45.
[39]C. H. Park, S. B. Zhang and Su-Huai Wei. Origin of p-type doping difficulty in ZnO:The impurity perspective. Phys. Rev. B,2002,66,073202.
[40]D. C. Look and B. Claflin. P-type doping and devices based on ZnO. physica status solidi (b), 2004.241,624.
[41]Kyoung-Kook Kim, Hyun-Sik Kim, Dae-Kue Hwang, Jae-Hong Lim and Seong-Ju Park. Realization of p-type ZnO thin films via phosphorus doping and thermal activation of the dopant. Appl. Phys. Lett.,2003,83.63.
[42]Ya.I.Alivov, D. C. Look, M. V. Chukichev and B. M. Ataev. Observation of 430 nm electroluminescence from ZnO/GaN heterojunction light-emitting diodes. Appl. Phys. Lett.. 2003,83,2943.
[43]Ya. I. Alivov, D. C. Look, M. V. Chukichev, D. M. Bagnall, B. M. Ataev and and A. K. Omaev. Fabrication and characterization of n-ZnOOp-AlGaN heteroj unction light-emitting diodes on 6H-SiC substrates.
[44]Dae-Kue Hwang, Soon-Hyung Kang, Jae-Hong Lim, Eun-Jeong Yang, Jin-Yong Oh, Jin-Ho Yang and Seong-Ju Park. p-ZnO/n-GaN heterostructure ZnO light-emitting diodes. Appl. Phys. Lett.,2005,86,222101.
[45]Min-Chang Jeong, Byeong-Yun Oh, Moon-Ho Ham, and Jae-Min Myoung. Electroluminescence from ZnO nanowires in n-ZnO film/ZnO nanowire array/p-GaN film heteroj unction light-emitting diodes. Appl. Phys. Lett.,2006,88,202105.
[46]Min-Chang Jeong, Byeong-Yun Oh, Moon-Ho Ham, Sang-Won Lee, and Jae-Min Myoung. ZnO-Nanowire-Inserted GaN/ZnO Heterojunction Light-Emitting Diodes. Communications, 2007,4,568.
[47]Jeong-M. Choi, Seongil Im. Ultraviolet enhanced Si-photodetector using p-NiO films. Applied surface science,2005,244,435-438.
[48]Hiromichi Ohta, Masao Kamiy, Toshio Kamiy, Masahiro Hirano, Hideo Hosono. UV-detector based on pn-heterojunction diode composed of transparent oxide semiconductors, p-NiO/ZnO. Thin Solid Films,2003,445,317-321.
[49]Hui Sun, Qi-Feng Zhang and Jin-LeiWu. Electroluminescence from ZnO nanorods with an n-ZnO/p-Si heterojunction structure. Nanotechnology,2006,17,2271-2274.
[50]Peiliang Chen, Xiangyang Ma and Deren Yang. Ultraviolet electroluminescence from ZnO/p-Si heteroj unctions. J. Appl. Phys.,2007,101,053103.
[51]Xiangyang Ma, Peiliang Chen, Dongsheng Li and Deren Yang. Electroluminescence from ZnO/n+-Si Heterojunction. Solid State Phenomena,2008,131,625-628.
[52]Peiliang Chen, Xiangyang Ma, Dongsheng Li, Yuanyuan Zhang, and Deren Yang. Bidirectional direct-current electroluminescence from i-MgxZnl-xO/n-ZnO/SiOx double-barrier heterostructures on Si. Appl. Phys. Lett.,2009,94,061110.
[53]N.M. Lawandy and R. M. Balachandran. Random laser. Nature,1995,373,204.
[54]H.Cao, Y.Ling, J.Y. Xua, A.L. Burina and R.P.H. Chang. Lasing with resonant feedback in random media. Physica B,2003,338,215-218.
[55]Diederik Wiersma. The smallest random laser. Nature,2000,406,132.
[56]Hui Cao. Lasing in random media. Waves Random Media,2003,13, R1-R39.
[57]H. Cao, Y. G. Zhao. H. C. Ong. S. T. Ho, J. Y. Dai, J. Y. Wu and R. P. H. Chang. Ultraviolet lasing in resonators formed by scattering in semiconductor polycrystalline films. Appl. Phys. Lett.,1998,73,3656.
[58]H. Cao and Y. G Zhao. Random Laser Action in Semiconductor Powder. Phys. Rev. Lett., 1999.82,2278.
[59]Sunglae Cho, Jing Ma, Yunki Kim, Yi Sun, George K. L. Wong and John B. Ketterson. Photoluminescence and ultraviolet lasing of polycrystalline ZnO thin films prepared by the oxidation of the metallic Zn. Appl. Phys. Lett.,1999,75,2761.
[60]Michael H. Huang, Samuel Mao, Henning Feick, Haoquan Yan, Yiying Wu, Hannes Kind, Eicke Weber. Richard Russo and Peidong Yang. Room-Temperature Ultraviolet Nanowire Nanolasers. Science,292,1897.
[61]S. F. Yu, Clement Yuen, S. P. Lau and H. W. Lee. Zinc oxide thin-film random lasers on silicon substrate. Appl. Phys. Lett.,2004,84,3244.
[62]Clement Yuen, S. F. Yu, Eunice S. P. Leong, H. Y. Yang, S. P. Lau and N. S. Chen. Low-loss and directional output ZnO thin-film ridge waveguide random lasers with MgO capped layer. Appl. Phys. Lett.,2005,86,031112.
[63]Sheng Chu, Mario Olmedo, Zheng Yang, Jieying Kong and Jianlin Liu. Electrically pumped ultraviolet ZnO diode lasers on Si. Appl. Phys. Lett.,2008,93,181106.
[64]Hai Zhu, Chong-Xin Shan, Bin Yao, Bing-Hui Li, Ji-Ying Zhang,Zheng-Zhong Zhang, Dong-Xu Zhao, De-Zhen Shen, Xi-Wu Fan, You-Ming Lu and Zi-Kang Tang. Ultralow-Threshold Laser Realized in Zinc Oxide. Adv. Mater.,2009,21,1613-1617.
[65]Hai Zhu, Chong-Xin Shan, Ji-Ying Zhang, Zhen-Zhong Zhang, Bing-Hui Li, Dong-Xu Zhao, Bin Yao, De-Zhen Shen, Xi-Wu Fan, Zi-Kang Tang, Xianghui Hou and Kwang-Leong Choy. Low-Threshold Electrically Pumped Random Lasers. Adv. Mater.,2010,22,1877-1881.
[66]H. K. Liang, S. F. Yu and H. Y. Yang. Directional and controllable edge-emitting ZnO ultraviolet random laser diodes.
[67]Xiangyang Ma, Peiliang Chen, Dongsheng Li, Yuanyuan Zhang and Deren Yang. Electrically pumped ZnO film ultraviolet random lasers on silicon substrate. Appl. Phys. Lett.,2007,91, 251109.
[68]Tsukazaki, A., Ohtomo, A., Nakano, M., Kawasaki, M. Photoinduced insulator-to-metal transition in ZnO/Mg0.15Zn0.85O heterostructures. Appl. Phys. Lett.,2008,92,052105.
[69]C. W. Sun, P. Xin, C. Y. Ma, Z. W. Liu, and Q. Y. Zhang. Optical and electrical properties of Znl-xCdxO films grown on Si substrates by reactive radio-frequency magnetron sputtering. Appl. Phys. Lett.,2006,89,181923.
[70]A. Abdolahzadeh Ziabari and F.E. Ghodsi. Synthesis and characterization of nanocrystalline CdZnO thin films prepared by sol-gel dip-coating process. Thin Solid Films.2011.520. 1228-1232.
[71]Th. Gruber, C. Kirchner, R. Kling. F. Reuss and A. Waag. Optical and structural analysis of ZnCdO layers grown by metalorganic vapor-phase epitaxy. Appl. Phys. Lett.,2003,83.3290.
[72]I. A. Buyanova, J. P. Bergman, G. Pozina, W. M. Chen, S. Rawal, D. P. Norton and S. J. Pearton, A. Osinsky and J. W. Dong. Mechanism for radiative recombination in ZnCdO alloys. Appl. Phys. Lett.,2007,90,261907.
[73]T. Makino, Y. Segawa, M. Kawasaki, A. Ohtomo, R. Shiroki, K. Tamura, T. Yasuda and H. Koinuma. Band gap engineering based on MgxZnl-xO and CdyZnl-yO ternary alloy films. Appl. Phys. Lett.,2001,78,1237.
[74]S. Sadofev, S. Blumstengel, J. Cui, J. Puls, S. Rogaschewski, P. Schafer and F. Henneberger. Visible band-gap ZnCdO heterostructures grown by molecular beam epitaxy. Appl. Phys. Lett.,2006,89,201907.
[75]Junji Ishihara,ar Atsushi Nakamura, Satoshi Shigemori, Toru Aoki and Jiro Temmyo. Znl-xCdxO systems with visible band gaps. Appl. Phys. Lett.,2006,89,091914.
[76]Vishnukanthan Venkatachalapathy, Augustinas Galeckas, Mareike Trunk, Tianchong Zhang, Alexander Azarov, and Andrej Yu. Kuznetsov. Understanding phase separation in ZnCdO by a combination of structural and optical analysis. Phys. Rev. B,2011,83,125315.
[77]Fazhan Wang, Zhizhen Ye, Dewei Ma, Liping Zhu, Fei Zhuge. Formation of quasi-aligned ZnCdO nanorods and nanoneedles. J. Crystal Growth,2005,283373-377.
[78]L. Li, Z. Yang, J. Y. Kong, and J. L. Liu. Blue electroluminescence from ZnO based heterojunction diodes with CdZnO active layers. Appl. Phys. Lett.,2009,95,232117.
[79]Lin Li, Zheng Yang and Jianlin Liu. Cyan electroluminescence from n-ZnO/i-CdZnO/p-Si heterojunction diodes. Mater. Res. Soc. Symp. Proc,2010,1201.
[80]A. Dev, J. P. Richters, J. Sartor, H. Kalt, J. Gutowski and T. Voss. Enhancement of the near-band-edge photoluminescence of ZnO nanowires:Important role of hydrogen incorporation versus Plasmon resonances. Appl. Phys. Lett.,2011,98,131111.
[81]Y. F. Lu, H. Q. Ni, Z. H. Mai and Z. M. Ren. The effects of thermal annealing on ZnO thin films grown by pulsed laser deposition. J. Appl. Phys.,2000,88,498.
[82]Jiandong Ye, Shulin Gu, Shunmin Zhu, Tong Chen, Liqun Hu, Feng Qin, Rong Zhang, Yi Shi and Youdou Zheng. The growth and annealing of single crystalline ZnO films by low-pressure MOCVD. J. Crystal Growth.2002,243,151-156.
[83]Puchert, M. K., Timbrell, P. Y. and Lamb, R. N. Postdeposition annealing of radio frequency magnetron sputtered ZnO films. J. Vacuum Science& Technology A,1996,14,2220.
[84]F. K. Shan, G. X. Liu, W. J. Lee, G. H. Lee, I. S. Kim and B. C. Shin. Aging effect and origin of deep-level emission in ZnO thin film deposited by pulsed laser deposition. Appl. Phys. Lett.,2005,86,221910.
[85]Yingling Yang, Hongwei Yan, Zhengping Fu, Beifang Yang, Linsheng Xia, Yuandong Xu, Jian Zuo and Fanqing Li. Photoluminescence and Raman studies of electrochemically as-grown and annealed ZnO films. Solid State Communications,2006,138,521-525.
[86]Yanfa Yan, M. M. Al-Jassim, and Su-Huai Wei. Oxygen-vacancy mediated adsorption and reactions of molecular oxygen on the ZnO(1010) surface. Phys. Rev. B,2005,72,161307.
[87]Chunming Jin, Ashutosh Tiwari and Roger J. Narayan. Ultraviolet-illumination-enhanced photoluminescence effect in zinc oxide thin films. J. Appl. Phys.,2005,98,083707.
[88]Yanhong Lin, Dejun Wang, Qidong Zhao, Ziheng Li, Yudan Ma and Min Yang. Influence of adsorbed oxygen on the surface photovoltage and photoluminescence of ZnO nanorods. Nanotechnology,2006,17,2110-2115.
[89]Wen-Yan Sua, Jing-Shun Huang and Ching-Fuh Lina. Improving the property of ZnO nanorods using hydrogen peroxide solution. J. Crystal Growth,2008,310,2806-2809.
[90]Jun-Yan Zhang, Qi-Feng Zhang, Tian-Song Deng and Jin-Lei Wua. Electrically driven ultraviolet lasing behavior from phosphorus-doped p-ZnO nanonail array/n-Si heterojunction. Appl. Phys. Lett.,2009,95,211107.
[91]Eunice S. P. Leong. S. F. Yu and S. P. Lau. Directional edge-emitting UV random laser diodes. Appl. Phys. Lett.,2006,89,221109.
[92]Xiangyang Ma, Jingwei Pan, Peiliang Chen, Dongsheng Li, Hui Zhang, Yang Yang, and Deren Yang. Room temperature electrically pumped ultraviolet random lasing from ZnO nanorod arrays on Si. Optics Express,17,14426.
[93]S. Sadofev, S. Kalusniak, J. Puls, P. Schafer, S. Blumstengel and F. Henneberger. Visible-wavelength laser action of ZnCdO/(Zn.Mg)O multiple quantum well structures. Appl. Phys. Lett.,2007,91.231103.
[94]Won Park.Gyu-Chul, Miyoung Kim and Stephen J. Pennycook. Quantum Confinement Observed in ZnO/ZnMgO Nanorod Heterostructures. Adv. Mater.2003,15(6).
[95]Diederik S. Wiersma. Light diffusion with gain and random lasers. Phys. Rev. E,1996,54, 4256.
[96]Mariano A. Zimmler, Jiming Bao, Federico Capasso, Sven Muller and Carsten Ronning. Laser action in nanowires:Observation of the transition from amplified spontaneous emission to laser oscillation. Appl. Phys. Lett.,2008,93,051101.
[97]N.M. Lawandy, R. M. Balachandran, A. S. Gomes and E. Sauvain. Laser action in strongly scattering media. Mature,1994,368,436.
[98]Kwang Joo Kim and Young Ran Park, Large and abrupt optical band gap variation in In-doped ZnO. Appl. Phys. Lett.,2001,78,475.
[99]Kuo-Feng Lin, Hsin-Ming Cheng, Hsu-Cheng Hsu, Li-Jiaun Lin and Wen-Feng Hsieh, Band gap variation of size-controlled ZnO quantum dots synthesized by sol-gel method. Chem. Phys. Lett.,2005,409,208.
[100]Kuo-Feng Lin, Hsin-Ming Cheng, Hsu-Cheng Hsu and Wen-Feng Hsieh. Band gap engineering and spatial confinement of optical phonon in ZnO quantum dots. Appl. Phys. Lett.,2006,88,263117.
[101]Yusuke Ogawa and Shinobu Fujihara. Blue Luminescence of MgZnO and CdZnO Films Deposited at Low Temperatures. J. The Electrochemical Society,2007,154,283-288.
[102]Seoung-Hwan Park, Doyeol Ahn and Bun-Hei Koo. Optical gain characteristics in (1120)-oriented CdZnO/MgZnO quantum wells emitting at 360-400 nm. Semicond. Sci. Technol.. 2010,25045016.
[103]Yasemin Caglar, Mujdat Caglar, Saliha Ilican and Aytunc Ates. Morphological, optical and electrical properties of CdZnO films prepared by sol-gel method. J. Phys. D:Appl. Phys., 2009,42,065421.
[104]A. Zaouia, M. Zaouia, S. Kacimia, A. Boukorttb and B. Bouhafsa. Stability and electronic properties of ZnxCdl-xO alloys. Materials Chemistry and Physics,2010,120,98-103.
