在本論文中首先利用射頻磁控濺鍍系統於不同工作壓力下成長氧化鋅薄膜於矽基板上，隨著工作壓力增加其電阻率有隨之下降趨勢，且在不進行熱處理條件下其最低電阻率可達4.3×10-3 Ω-cm，藉由光學穿透率量測，當波長大於430nm時其穿透率達90%以上，且在波長380nm時穿透率可達80%。在高工作壓力下成長可以降低其非輻射復合速率進而增進其載子生命週期，其非輻射復合速率降低之原因是由於氧缺陷減少所致。此外，隨著工作壓力之增加其薄膜吸收係數亦隨之降低且光學能隙有增大之趨勢。
此外，利用此共濺鍍系統可在室溫下成長出具矽奈米顆粒之氧化鋅薄膜。在共濺鍍過程中調變矽靶之射頻功率，可成長出不同結晶結構矽摻雜氧化鋅薄膜。此部分之研究利用高解析穿透式電子顯微鏡、X光繞射儀及傅立葉轉換紅外線光譜儀分析矽奈米顆粒於氧化鋅基材內之結晶狀態及鍵結型態，最後並利用光激發光譜分析比較方式，可證明出矽奈米顆粒之量子侷限效應。
本研究利用此射頻系統共濺鍍成長氮化鋁摻雜氧化鋅薄膜於藍寶石基板上，薄膜成長過程中基板不升溫且調變氮氣對氬氣之比例，為了分析出不同氮氣比例下對於氮化鋁摻雜氧化鋅薄膜之影響，將針對結晶結構及鍵結型態做較深入之分析。在適當比例之氮氣環境下成長氮化鋁摻雜氧化鋅薄膜，並進行450oC熱退火活化處理，可促進其鋅原子與氮原子鍵結並進而製作出P型氧化鋅薄膜。根據低溫光激發光譜之量測可計算出電洞位階之束縛能約0.16 eV，且由於氮原子填補了氧缺陷位置，因此增進了氮化鋁摻雜氧化鋅薄膜內載子生命週期。
最後，利用氣相冷凝系統及共濺鍍系統成長高品質本質氧化鋅、N型氧化鋅及P型氧化鋅薄膜於藍寶石基板上，製作出氧化鋅同質接面發光二極體，其電流-電壓特性曲線呈現出一整流特性，且在電激發光光譜量測下，其發光中心波段位在387nm左右，此現象是因為輻射複合發光皆位在高品質本質氧化鋅區域內所致。

In this thesis, zinc oxide (ZnO) thin films were deposited on Si substrates using various working pressures by magnetron sputter. The resistivity of the deposited ZnO films decreases with working pressure and the resistivity of 4.3x10-3Ω-cm can be obtained without post annealing. According to the optical transmittance measurements, the optical transmittance above 90% in the wavelength longer than 430nm and about 80% in the wavelength of 380nm can be found. Using time-resolved photoluminescence measurement, the carrier lifetime increases with working pressure due to the reduction of nonradiative recombination rate. The reduction of nonradiative recombination rate is originated from the decrease of oxygen vacancies in the ZnO films deposited at a higher working pressure. Besides, by increasing the working pressure, the absorption coefficient was decreased and the associated optical energy gap of ZnO thin films was increased.
Moreover, a cosputtering system was used to deposit silicon nanoclusters embedded in zinc oxide matrix (Si:ZnO) at low temperature without post-annealing. By adjusting the radio frequency power of the Si target during co-sputtering, Si:ZnO films with various crystallographic structures can be obtained. Silicon nanoclusters embedded in the zinc oxide matrix were examined using a high resolution transmission electron microscope (HRTEM), X-ray diffractometer (XRD) and Fourier transformation infrared (FTIR) spectrometry. By comparing with photoluminescence (PL) spectra, we can clearly identify quantum confinement effect of silicon nanoclusters embedded in the ZnO matrix.
For the fabrication of p-type ZnO, AlN codoped ZnO films were deposited on sapphire substrates at low temperature using a co-sputter system under various N2/(N2+Ar) flow ratios. To investigate the nitrogen function, the ratio of nitrogen ambient was varied during co-sputtering. AlN codoped ZnO films with various crystallographic structures and bonding configurations were measured. With an adequate nitrogen atmosphere deposition condition and post-annealing temperature at 450oC, the p-type conductive behaviors of AlN codoped ZnO films were achieved due to the formation of Zn-N bonds. According to the low temperature photoluminescence (LT-PL) spectra, the binding energy (EA) of 0.16 eV for N acceptors can be calculated. Using time-resolved photoluminescence measurement, the carrier lifetime in AlN codoped ZnO films increases due to the reduction of oxygen vacancies caused by the occupation of adequate nitrogen atom.
Finally, high quality i-ZnO, n-ZnO:In and p-type ZnO thin films were grown on sapphire substrates using vapor cooling condensation method and cosputter technique. Nonlinear rectifying IV characteristic was measured. The ultraviolet emission peak at 387 nm observed in the p-i-n homostructed-light-emitting diode was attributed to the radiative recombination of near-band edge in the i-ZnO layer.

chapter 1
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chapter 2
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