本文主要探討單斜氧化鎵紫外光光檢測器的製作，藉由改變溫度、氣體流量、氣體種類，成功製作奈米線形式和薄膜形式的單斜氧化鎵紫外光光檢測器。
起初，我們藉由加熱氮化鎵/氧化鋁基板成長氧化鎵奈米線，奈米線的平均長度、平均直徑皆隨成長溫度增加而增加。此外，在高溫下(例：1050 和1100 ℃)可以達到較好的單斜氧化鎵品質。在入射光波長為255奈米且外加偏壓為5伏特下，光檢測器的響應可達每瓦3.72×10-1毫安培。
接著，我們藉由化學氣相沉積法，在固定氬氣流量且改變氧氣流量下，成長單斜氧化鎵奈米線。奈米線的平均長度隨氧氣流量增加而減少。然而，奈米線的平均直徑隨氧氣流量增加而增加。在外加偏壓為5伏特下，氧氣流量為1、2、4、6標準狀態每分鐘立方公分的單斜氧化鎵奈米線光檢測器的紫外光對可見光的拒斥比分別為315、11742、12258、12105。因此，藉由調變氧氣流量可以讓紫外光對可見光的拒斥比增加2個數量級。
最後，我們將氮化鎵磊晶層放置在高溫含氧的環境下，並藉由爐管氧化法成長單斜氧化鎵薄膜，薄膜的粗糙度隨成長溫度增加而增加。在外加偏壓為5伏特下，成長溫度為1000、1025、1050、1100℃的單斜氧化鎵薄膜光檢測器的紫外光對可見光的拒斥比分別為35669、79130、2935、1250。

This thesis focuses mainly on the fabrication of UV photodetectors based on β-Ga2O3. By varying temperature, gas flow and gas kind, we successfully fabricate nanowire-type or thin-film-type β-Ga2O3 UV photodetectors.
At first, we report the growth of nanowires by heating the GaN/sapphire template. It was found that average length and average diameter of the nanowires all increased with the increase of the growth temperature. It was also found that β-Ga2O3 nanowires with good crystal quality could be achieved only at high temperatures (i.e., 1050 and 1100 ℃). With an incident light wavelength of 255 nm and an applied bias of 5 V, it was found that measured responsivity of the photodetector was 3.72×10-1 mA/W.
Then, we report the β-Ga2O3 nanowires prepared with different oxygen flow and constant argon flow by the chemical vapor deposition method. It was found that the average length of nanowires increased with the decrease of the oxygen flow. However, the average diameter of the nanowires increased with the increase of the oxygen flow. With an applied bias of 5 V, it was found that the UV-to-visible rejection ratios of β-Ga2O3 nanowire photodetectors grown at 1, 2, 4, and 6 sccm oxygen flow were 315, 11742, 12258 and 12105, respectively. By varying the oxygen flow, we can make UV-to-visible rejection ratio increased by 2 orders of magnitude.
Finally, we report the growth of β-Ga2O3 thin film by furnace oxidation of GaN epitaxial layer at high temperature in oxygen containing ambient. It was found that the roughness of β-Ga2O3 thin film increased with the increase of the growth temperature. With an applied bias of 5 V, it was found that the UV-to-visible rejection ratios of β-Ga2O3 thin film photodetectors grown at 1000, 1025, 1050, and 1100 ℃ were 35669, 79130, 2935 and 1250, respectively.

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