本實驗中，金屬(Al )/氧化鉿(HfO2)/半導體(p-Si)結構的電容器成功地製作出，氧化鉿(HfO2)薄膜使用射頻磁控濺鍍法沈積。並對元件作基本的變溫電性量測，溫度範圍在77 K至465 K，並充分討論漏電流機制。結果顯示在累積區偏壓為1 V時漏電流約為10-6 A/cm2，介電常數為17.00，氧化鉿(HfO2)薄膜的厚度為23.2 nm，溫度範圍在450 K以上，所得到的結果顯示在低電場( 2.2 MV/cm)，得金屬(Al)/氧化鉿(HfO2)界面的電流傳導機制為蕭基發射所主導。溫度在77 K時，所得到的結果顯示在高電場( 2.6 MV/cm)， 電流傳導機制為傅勒-諾德翰穿隧所主導，並可利用蕭基發射及佛勒-諾德翰穿隧分析的結果求得在氧化鉿薄膜中電子的有效質量為0.4m0 (等效厚度為5.33 奈米(nm)) ，並可得到鋁/氧化鉿的位障高為0.94 eV。至於物性分析方面，我們也作了二次離子質譜儀縱深分佈分析(SIMS)、X光繞射分析(XRD)、穿透式電子顯微鏡照相分析(TEM)、電子能譜儀(ESCA)等分析薄膜的物理性質，亦有了很多收穫。
同時也製備金屬(Al)/氧化鉿(HfO2)/半導體(p-Si) n通道型的場效電晶體，並對元件作基本電性測量，如IDS-VDS，IDS-VGS。發現臨界電壓等於1.1 V，最小的次臨界斜率等於241 mV/dec.，在VDS=0.1 V時，Ion/Ioff的比例有四個數量級。由次臨界斜率St=2.3(kT/q)[1+(CD+Cit)/Cox]的計算可以得到界面缺陷電荷密度等於1.4 1013 cm-2-eV-1。由於HfO2的熱穩定性好，所以HfO2非常適合當作下一代電晶體的閘極氧化層材料。

In this work, the electrical properties of HfO2 thin films as function of temperature were investigated. The temperature range is from 77 K to 465 K. Al/HfO2/p-Si metal-oxide-silicon (MOS) capacitors were fabricated. The HfO2 gate dielectrics were deposited by RF magnetron sputtering. The leakage current of Al/HfO2/p-Si MOS capacitors was about 10-6 A/cm2 at 1V in accumulation mode. The dominant conduction mechanism is Schottky emission at high temperatures ( 450 K) and low electric fields ( 2.2 MV/cm). At 77 K, the conduction mechanism is Fowler-Nordheim tunneling at high electric fields ( 2.6 MV/cm). Both the intercept of the fitted Schottky emission line and the slope of the fitted Fowler-Nordheim tunneling line are functions of barrier height and electron effective mass in HfO2. An analysis of self-consistent iteration method was used to show that the extracted Al/HfO2 barrier-height and electron effective mass in the HfO2 film (equivalent oxide thickness=5.33 nm) are about 0.94 eV and 0.4m0, respectively. Secondary ion mass spectrometry (SIMS), X-ray diffraction (XRD), electron spectroscopy for chemical analysis (ESCA) and transmission electron microscope (TEM) images were used to examine the material properties.
N-channel metal-oxide-semiconductor field effect transistors using HfO2 gate oxide were also fabricated. The IDS-VDS and IDS-VGS characteristics were measured. The threshold voltage was 1.1 V. The subthreshold swing was 241 mV/dec.. The ION/IOFF is about 104. Since St=2.3(kT/q)[1+(CD+Cit)/Cox], the interface trapped charge density Dit is 1.4 1013 cm-2-eV-1. In the future, MOSFETs with HfO2 gate oxide will be a promising candidate for future generations of MOSFETs.

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