本實驗利用射頻磁控濺鍍機(RF Magnetron Sputter)在923K下，於c面藍寶石基板上製程In2O3/ZnO之異構超晶格薄膜。
首先，藉由改變濺鍍時間，尋找較佳的單層膜製程參數，透過X射線繞射(XRD)、Phi掃描以及低掠角X射線繞射(GIXRD)探討不同參數下薄膜的結構是否為磊晶，並透過X射線反射率(XRR)與GenX軟體擬合得知薄膜厚度、粗糙度與密度，進一步堆疊數個週期以製程超晶格結構。
在15K~290K的溫度區間量測變溫過程的電阻變化(RT)，以及再照射紅光(633nm)、綠光(514nm)與藍光(454nm)雷射，並發現在綠光以及藍光照射下，對電導率取自然對數以及溫度的負二分之一與負四分之一次方做圖，發現定程躍遷(fixed range hopping)與變程躍遷(variable range hopping)主導不同溫度區間的影響，顯示光子可能具有增強熱激發效率之現象。

The superlattices of In2O3/ZnO have been successfully fabricated by RF magnetron sputtering on c-oriented sapphire substrates at 923K. The film-substrate epitaxy is determined by X-ray diffraction (XRD) data based on the omega-2theta scans, Phi scans and Grazing Incidence X-ray Diffraction (GIXRD) of 2theta scans at a fixed small incident angle of omega. Meanwhile, the X-ray reflectivity (XRR) method was also employed to acquire the thickness, density and roughness of the heterojunction multilayered samples. The temperature-dependent electrical characteristics were studied from 15 K to 290 K by measurement of the resistivity as a function of temperature to obtain an RT curve either in the dark or under illumination of individual lasers at a different wavelength of 633 nm (red), 514 nm (green), or 454 nm (blue) on the samples. The conduction mechanism of the heterojunction superlattices are understood as photo-assisted thermal activation in the context of band conduction or hopping conduction as judged by their exponential functional dependence on T^(-1), T^(-1/2), or T^(-1/4). In band conductions, electrons are set free from bonding by thermally excitation from a donor state into the conduction band. In hopping conductions, the electrons, never set free, hop from one impurity atom to another. The distinct photo-thermal effects are investigated.

論文審定書 i
Acknowledgment ii
摘要 iii
Abstract iv
Content v
Figures vi
Tables ix
I Introduction 1
II Experimental 3
A. Single-layer films 4
B. Bilayer films 5
C. Multilayer films 6
III Results and Discussion 8
III-I Structural Properties 8
A. Single-layer comparison 8
B. Bilayer comparison 21
C. Multiple layer comparison 26
III-II Photoelectronic Characterization 31
IV Conclusion 45
References 47
Appendices 51

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