本論文使用反應性磁控濺鍍系統沈積ZrO2薄膜作為閘極氧化層之應用，並探討不同製程對ZrO2薄膜沈積在矽基材上時所生成的中介層的影響。本實驗第一部分探討在空白矽晶片上沈積ZrO2薄膜以及在空白矽晶片上預先濺鍍一層極薄的Zr金屬層來改善ZrO2與Si之間的的界面品質，並探討不同的後續熱處理氣氛(氧氣或氮氣)及溫度(300℃、500℃、700℃)對材料性質與電性的影響。第二部分則著重探討ZrO2薄膜沈積在以N2O及NH3低溫(450℃)電漿氮化矽基材之熱穩定性與其對電性的影響。
　　本實驗使用低掠角X光繞射儀對薄膜的結構及結晶性進行分析。使用拉塞福背向散射分析儀做薄膜組成成份與密度之分析。使用X光光電子能譜分析儀對不同製程的ZrO2薄膜進行表面化學鍵結分析、定量分析與縱深分析；此外，並使用歐傑電子能譜儀進行縱深分析。薄膜的厚度使用穿透式電子顯微鏡鑑定，並觀察其微結構。光學性質方面，使用橢圓偏光儀量測薄膜的折射率，並可同時模擬薄膜與中介層的厚度及組成成份。電性方面，使用Picoampere meter(HP 4140B)量測I-V曲線，而C-V曲線則使用LCR meter(HP 4284)進行量測。
　　實驗結果第一部分顯示，初鍍的ZrO2薄膜為非晶質薄膜，但含有介穩的正方晶相奈米微晶，而且氧的含量大於計量比。退火後，晶粒些微成長、薄膜緻密化、中介層比例增加，且漏電流亦下降。預先濺鍍一層金屬Zr可降低中介層所佔厚度比例，但其捕獲電荷較多，顯示其氧化層品質較差，並導致其漏電流亦較大。兩種製程的薄膜內的有效電荷均為正電荷，隨著退火溫度上升而增加，但在700℃退火後則減少。
　　實驗結果第二部分顯示，電漿氮化矽基材所產生的SiOxNy。可有效阻止中介層的成長，尤其以使用NH3的效果較佳，但效果並不如預先濺鍍一層金屬層明顯。ZrO2薄膜沈積在電漿氮化矽基材的捕獲電荷較沈積在空白矽晶片上少，漏電流亦較低；700℃退火後，以N2O電漿氮化的有效電荷較少，而以NH3電漿氮化的捕獲電荷較少、熱穩定性較佳。

　　ZrO2 thin films are deposited by reactive magnetron sputtering as application for gate oxide, and the effects of various processing methods upon the interfacial layer formed when ZrO2 deposited on Si is investigated. In the first section of the experiment, the interfacial characters of ZrO2 thin films deposited on bare silicon substrate and on silicon substrate with an pre-sputtered ultrathin Zr metal layer is studied; furthermore, the effects of various post- annealing atmosphere (O2 or N2) and temperatures (300℃, 500℃, 700℃) upon the material and electrical characteristics is also examined. The second section of the experiment focuses on the thermal stability and electrical properties of ZrO2 thin films deposited on low temperature (450℃) N2O and NH3 plasma nitrided Si surface.
　　Glancing incident angle x-ray diffraction (GIAXRD) is utilized to analyze the structure and crystallinity of the thin films. The composition and density of the thin films are determined by Rutherford ackscattering spectrometry (RBS). X-ray photoelectron spectroscopy (XPS) is applied for surface bonding analysis, quantification and depth profile. Elemental depth profiles are also measured by Auger electron spectroscopy (AES). The thickness of the thin films is determined by transmission electron microscope (TEM), and the microstructure is also characterized. For optical properties, ellipsometer is used not only to measure the refractive index of the thin films, but also to simulate the thickness and composition of the ZrO2 layer and the interfacial layer. For electrical properties, HP 4140B is used to measure the I-V curves, and the C-V curves are obtained by HP 4284.
　　The results of the first section reveal that as-deposited ZrO2 thin films are amorphous, but contain metastable tetragonal nanocrystallites, and the oxygen content is beyond its stoichiometric value. After annealing, the growth of the nanocrystallites is insignificant, the films densify, the thickness ratio of the interfacial layer increase, and the leakage current decrease. Pre-sputtering an ultrathin Zr metal layer decreases the thickness ratio of the interfacial layer, but the larger amount of oxide traps indicates the inferior quality of the oxide, and results in larger leakage currents. The thin films of the two different processing methods exhibit positive effective charges, which increase with increasing post-annealing temperature, but decrease after annealing at 700℃.
　　Based on the results of the second section, silicon oxynitride grown by plasma nitridation reduces the growth of the interfacial layer effectively, particularly using NH3, but is not as effective as pre-sputtering an ultrathin Zr layer. ZrO2 thin films deposited on plasma nitrided silicon substrate exhibit fewer oxide traps, and the leakage current is thus lower. After annealing in 700℃, the N2O nitrided system possesses fewer positive effective charges, while the NH3 nitrided system possesses fewer oxide traps and better thermal stability.

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