臺灣博碩士論文加值系統

氮化鎵材料擁有良好的光電特性，已廣泛的應用於製作光電元件上，在製作以氮化鎵為材料的元件時，蕭特基接觸扮演了極重要的角色，因此我們必須發展出具有不錯的蕭特基位障高度以及熱穩定性高的蕭特基接觸，並且應用於製作光電元件使得能夠操作於高溫的情況。
本論文是探討在n型氮化鎵上製作蕭特基接觸(Schottky con-tact)之研究，以鎳/金(Ni-Au)為蕭特基接觸金屬，製作n型氮化鎵蕭特基二極體，利用電流－電壓(I-V)法量測蕭特基位障高度(Schottky barrier height)以及理想性因子(ideality factor)。由於位障高度為判別蕭特基接觸特性的重要指標，為了提高蕭特基位障高度及探討其熱穩定性，我們對蕭特基二極體進行熱處理的製程。本實驗的熱處理製程是使用高溫爐管在氮氣的環境下完成，熱處理溫度分別是300℃、400℃、500℃、550℃，熱處理時間有5min、10min、30min、60min。熱處理前的位障高度和理想性因子分別為0.89eV和1.2；經過一系列的熱處理後，發現在300℃和400℃的熱處理可以使位障高度獲得改善約0.19eV，顯示在此溫度下此氮化鎵蕭特基二極體具有很好的熱穩定性；而在500℃和550℃下長時間的熱處理則位障高度反而降低，甚至不再出現二極體整流特性。此外，實驗中也將上述熱處理製程應用於氮化鎵金屬-半導體-金屬(MSM)光檢測器的製作上，可以發現經過400℃ 30min的熱處理，金半金檢光器的暗電流可以從201μA降至0.125μA。

Since GaN-based material shows very good optoelectronic properties, it has been widely applied to fabricate optoelectronic devices. Schottky contact plays an important role in the fabrication of GaN-based devices. It is necessary to develop the Schottky contacts with high barrier height and good thermal stability for the applica-tion of optoelectronic devices to operate at high temperature.
In this study, Ni/Au Schottky contacts on n-GaN were fabricated and character-ized. The barrier height and ideality factor were extracted from the measurement of I-V curves. In order to enhance the barrier height and evaluate the thermal stability, the Schottky diodes were treated with different of thermal annealing processes. The thermal treatments were conducted under nitrogen ambient in a furnace tube. The temperature and time used for thermal treatment were from 300℃ to 550℃ and from 5min to 60min, respectively. From the results, we found that thermal treatments at 300℃ and 400℃ can be used to enhance about 0.19eV of barrier height. However thermal treatments at 500℃ and 550℃ for a long time will make barrier height de-grade. By the way, the dark current of MSM photodetectors can be significantly re-duced from 201μA to 0.125μA by thermal annealing at 400℃ for 30min.

封面內頁
簽名頁
授權書．．．．．．．．．．．．．．．．．．．．．．．．iii
中文摘要．．．．．．．．．．．．．．．．．．．．．．．iv
英文摘要．．．．．．．．．．．．．．．．．．．．．．．v
致謝．．．．．．．．．．．．．．．．．．．．．．．．．vi
目錄．．．．．．．．．．．．．．．．．．．．．．．．．vii
圖目錄．．．．．．．．．．．．．．．．．．．．．．．．ix
表目錄．．．．．．．．．．．．．．．．．．．．．．．．xi

第一章　緒論．．．．．．．．．．．．．．．．．．．．．1
1.1 研究背景與目的 ．．．．．．．．．．．．．．．1
1.2 論文架構．．．．．．．． ．．．．．．．．．4
第二章 金半接面原理與光檢測器工作原理．．．．．．．．5
2.1 金屬－半導體接面原理．．．．．．．．．．．．5
2.1.1 金屬－半導體歐姆接面．．．．．．．．．6
2.1.2 金屬－半導體蕭特基接面．．．．．．．．8
2.2 金屬－半導體－金屬光檢測器原理．．．．．．．13
第三章 元件製作與量測．．．．．．．．．．．．．．．．17
3.1 試片準備步驟．．．．．．．．．．．．．．．．17
3.2 蕭特基二極體之製作流程．．．．．．．．．．19
3.3 金屬－半導體－金屬光檢測器的製作流程．．．．20
3.4 蕭特基二極體特性量測．．．．．．．．．．．．23
3.5 金屬－半導體－金屬光檢測器電流－電壓特性．．25
第四章 結果與討論．．．．．．．．．．．．．．．．．．26
4.1 蕭特基二極體電流－電壓量測分析．．．．．．．26
4.2 XRD量測分析．．．．．．．．．．．．．．．．32
4.3 金屬-半導體-金屬光檢測器暗電流特性分析．．．33
4.4 金屬-半導體-金屬光檢測器光電流特性分析．．．35
第五章 結論．．．．．．．．．．．．．．．．．．．．．．40
參考文獻．．．．．．．．．．．．．．．．．．．．．．．41

【1】 M. A. Khan, J. N. Kuznia, A. R. Bhattarai, and D. T. Oslon, “ Metal semiconductor field effect transistor based on single crystal GaN, ” Appl. Phys. Lett. , Vol.62, pp.1786, 1993.
【2】 M.A. Khan, J. N. kuznia, D. T. Olson, W. J. Schaff, J. W. Burm, and M. S. Shur, “ Microwave performance of a 0.25μm gate AlGaN/GaN heterostructure field effect transistor, ”Appl. Phys. Lett. , Vol.65, pp.1121, 1994.
【3】 F. Ren, C. R. Abernathy, J. M. Van Hove, P. P. Chow, R. Hickman, J. J. Klaasen, R. F. Kopf, H. Cho, K. B. Jung, J. R. LaRoche, R. G. Wilson, J. Han, R.J. Shul, A. G. Baca, and S. J. Pearton, “ 300℃ GaN/AlGaN Heterojunction Bipolar Transis-tor, ” MRS. Internet J. Nitride Semicond. Res. , Vol.3, pp.41, 1998.
【4】 T. Mukai, D. Morita, and S. Nakamura, “ High-power UV In-GaN/AlGaN double-heterostructure LEDs, ” J. Crystal. Growth, Vol.189/190, pp.778, 1998.
【5】 G.S. Nakamura, “InGaN-based violet laser diodes,” Semicond. Sci. Technol. Vol.14, pp.27, 1999.
【6】 M.A. Khan, J. N. Kuznia, D. T. Olson, M. Blasingame, and A.R. Bhattarai, “ Schottky barrier photodetector based on Mg-doped p-type GaN film, ”Appl. Phys. Lett. , Vol.63, pp.2455, 1993.
【7】 M. Asif Khan, J. N. Kuznia, D.T. Olson, J. M. Van hove, M. Blasingame, L. F. Reitz, “ High-responsivity photoconductive ultraviolet sensors based on insulating single-crystal GaN epi-layers,” Appl. Phys. Lett. , Vol.60, pp.2917, 1992.
【8】 Z. C. Huang, D. B. Mott, P. K. Shu, R. Zhang, J. C. Chen, D. K. Wickenden, “ Optical quenching of photoconductivity in GaN photoconductors, ” J. Appl. Phys. , Vol.82, pp.2707, 1997.
【9】 Q. Chen, M. A. Khan, C. J. Sun, and J. W. Yang,“ Visi-ble-blind ultraviolet photodetectors based on GaN p-n junc-tions, ” Electron. Lett. , Vol.31, pp.1781, 1995.
【10】 D. Walker, A. Saxler, P. Kung, X. Zhang, M. Hamilton, D. Jiaz, M. Razeghi , “Visible blind GaN p-i-n photodiodes,” Appl. Phys. Lett. , Vol.72, pp.3303, 1998.
【11】E. Monroy, F. Calle, E. Munoz, F. Omnes, P. Gibart, J. A. Mu-noz, “ AlXGa1-XN: Si Schottky barrier photodiodes with fast re-sponse and high detectivity, ” Appl. Phys. Lett. , Vol.73, pp.2146, 1998.
【12】 E. Monroy, F. Calle, E. Munoz, and F. Omnes, “ Effects of Bias on the Responsivity of GaN Metal-Semiconductor-Metal Pho-todiodes”, Phys. Stat. Sol. (a), Vol.176, pp.157, 1999.
【13】A. C. Schmitz, A. T. Ping, M. Asif Khan, Q. Chen, J. W. Yang and I. Adesida,“ Mental contacts to n-type GaN, ”J. Elec-tron. Master. , Vol.27, pp.255-260, 1997.
【14】E. V. Kalinina, N. I. Kuznetsov, V. A. Dmiteiev, K. G. Irvine and C. H. Carter, “ Schottky barriers on n-GaN grown on SiC, ” J. Elctron. Mater. , Vol.25, pp.831-834, 1995.
【15】 S. N. Mohammad, Z. FaN, A. E. Botchkarev, W. Kim, O. Aktas, A. Salvadorand H. Morkoc, “ Near-ideal platinum-GaN Schottky diodes, ” Electron. Lett. , Vol.32, pp598-599, 1996.
【16】S. M. Sze. , “ Physics of Semiconductor Devices, ”Wiley Interscience, pp187, 2006.
【17】F. Braun, “ Uber die Stromleitung durch Schwefelmetalle, ”Ann. Phys. Chem. , Vol.153, pp.556, 1874.
【18】W. Schottky, “ Semiconductor Theory of the Blocking Layer,Naturwisenschaften, Vol.26, pp.843, 1938.
【19】V. Rajagopal Reddy, P. Koteswara Rao, “ Annealing tem-perature effect on electrical and structural properties of Cu/Au Schottky contact to n-type GaN, ” Microelectronic Science and Engineering, Vol.85, Issue.2, pp.470-476, 2007.
【20】V. Rajagopal Reddy, P. Koteswara Rao,“ Annealing effects on structural and electrical properties of Ru/Au on n-GaN Schottky contacts, ” Materials Science and Engineering B, Vol.137, Issues.1-3, pp.200-204, 2007.
【21】A. C. Schmitz, A. T. Ping, M. Asif Khan, Q Chen, J. W. Yang “Schottky barrier properties of various metals on n-type GaN,”Semicond Sci Technol Vol. 11, pp 1464-1467, 1996.
【22】N. Miura, T. Nanjo, M. Suita, T. Oishi, Y.Abe, “Thermal an-nealing effects on Ni/Au based Schottky contacts on n-GaN and AlGaN/GaN with insertion of high work function metal, ”Solid-State Electronics Vol 48, pp689-695, 2004.
【23】Y. K. Su, S. J. Chang, C. H. Chen, J. F. Chen, G. C. Chi, J. K. Sheu,W. C. Lai, J. M. Tsai,“GaN Metal-Semiconductor-Metal Ultraviolet Sensors With Various Contact Electrodes, ”IEEE Sensors Journal, Vol.2, NO.4, 2002.