我們研究氧化鋯電流機制和溫度與電場函釋有關，製備金屬（Al）/氧化鋯（ZrO2）/半導體（p-Si）結構的電容器，並對元件作基本的變溫電性量測，在負偏壓下，在越高溫時(375K~450K)以及在低電場下(0.81~1.40MV/cm)機制為修正型蕭基發射，從修正型蕭基發射方程式所萃取出來的能障高( )為1.06 eV，在高電場（1.50~2.25 MV/cm）及高溫之下(375K~450K)，ZrO2薄膜本體的電流傳導機制為修正型普爾-法蘭克發射所主導，所得到的ZrO2薄膜本體捕獲中心的能帶高為0.83 eV。在正偏壓下，低電場（0.20~0.60 MV/cm）及高溫之下(425K~450K)，ZrO2/Si界面間的電流傳導機制為蕭基發射所主導，其能障為1.0eV。從這些結果，我們可以得到Al/ ZrO2/p-Si的能帶圖
我們成功地製作了N通道的金屬（Al）/氧化鋯（ZrO2）/半導體（p-Si）的場效電晶體，我們使用射頻磁控濺鍍法沈積ZrO2薄膜，在基本電性上的表現，如：ID-VD，ID-VG及C-V等，，且發現臨界電壓約在0.20V，最小的次臨界斜率是272 mV/dec.，在VD=0.1V下，ION/IOFF的比例只有四個數量級之多。經由次臨界斜率St=2.3(kT/q)[1+(CD+Cit)/Cox]的計算，可以得到界面缺陷電荷密度（Dit）為1.35x1013 cm-2-eV-1。
接下來，至於材料物性方面，我們也作了SIMS、XRD和ESCA等分析，了解ZrO2薄膜組成。
經由和傳統SiO2電晶體作一比較，發現電晶體特性及相關參數沒有傳統SiO2電晶體好，但由於熱穩定性較Ta2O5好，所以ZrO2非常適合當作下一代電晶體的閘極氧化層材料。

The electrical conduction mechanism in zirconium oxide (ZrO2) thin films as a function of temperature T and electric field E was studied. Al/ZrO2/p-Si metal-insulator-semiconductor (MIS) capacitors were fabricated. With the Al electrode biased negative, the conduction mechanism in the electrical field of 0.81 MV/cm <E< 1.40 MV/cm and in the temperature range of 375 K <T< 450 K is found to be modified Schottky emission. The intrinsic barrier height between Al and ZrO2 is 1.06 eV. At higher electrical fields of 1.50 MV/cm <E< 2.25 MV/cm and higher temperatures of 375 K <T< 450 K, the electrical conduction is dominated by modified Poole-Frenkel emission. The extracted trap barrier is 0.83 eV. With the Al electrode biased positive, the conduction mechanism is found to be Schottky emission at the electrical field 0.20 MV/cm <E< 0.60 MV/cm and higher temperature range of 425 K <T< 450 K. The barrier height between Si and ZrO2 is 1.0 eV. Based on these results, an energy band diagram of the Al/ ZrO2/p-Si system is proposed.
N-channel metal-oxide-semiconductor field effect transistors (MOSFETs) using ZrO2 gate oxide were fabricated successfully. The ZrO2 films were deposited by RF magnetron sputtering. The C-V, ID-VD and ID–VG characteristics are measured. The threshold voltage was 0.20 V. The minimum subthreshold swing was 272 mV/dec. The ION/IOFF ratio is about 104 at VD=0.1 V. Since St=2.3(kT/q)[1+(CD+Cit)/Cox], the interface trapped charge density Dit is extracted to be about 1.35x1013 cm-2-eV-1.
Secondary ion mass spectrometry (SIMS), X-ray diffraction (XRD), electron spectroscopy for chemical analysic (ESCA) and transmission electron microscope (TEM) were used to examine the material properties of ZrO2.
A comparison with MOSFETs using SiO2 gate oxides was made. The ZrO2/Si interface is generally inferior compared with that of the SiO2/Si interface. But the ZrO2/Si interface is comparable to that of the Ta2O5/Si interface. The thermodynamic stability of ZrO2 gate oxide is much better than that of Ta2O5 gate oxide. In the future, MOSFETs with ZrO2 gate oxide will be a promising candidate for sub-0.1 mm MOSFETs.

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