此研究先以反應式離子束濺鍍法於SiO2基板上依不同的氧氬比沉積銅氧化物薄膜，由Ar:O2=3.5:2.5的比例沉積300 oC與400 oC的氧化銅和Ar:O2=4.2:0.7的比例沉積300 oC與400 oC的氧化亞銅薄膜，XRD證實各別為氧化銅、氧化亞銅結晶性佳的多晶薄膜。CuO與Cu2O薄膜載子濃度得到約為1014~1015 cm-3，其遷移率最好為300 oC的Cu2O薄膜得到11 cm2V-1s-1。CuO薄膜在室溫下沉積Cu指叉電極，利用金屬-半導體-金屬結構之光電二極體探討光電特性，該樣品入射光子與光電流呈線性關係，經量測結果在波長範圍400~1300 nm有光電流，且在700 nm可以得到最高光響應為43 mA/W，其快速的decay time小於1 μs，經計算後推測受RC limited影響。另外求得Cu/CuO接面其蕭特基位障為0.87 eV。這些特性結果有助於製作CuO材料光伏元件上使用。

Cupric oxide (CuO) and Cuprous oxide (Cu2O) thin films are deposited on SiO2/Si substrates by reactive ion beam sputter deposition at 300 ~ 400oC utilizing an anode layer ion source. Both argon and oxygen are passed simultaneously through the ion source to act as sputtering and reacting species, respectively. With an Ar:O2 ratio of 3.5:2.5, single phase polycrystalline CuO thin films are obtained. Ar:O2 ratio to 4.2:0.7 results in single phase polycrystalline Cu2O. The carrier concentration of CuO and Cu2O thin film are 1014 and 1015 cm-3, respectively. The mobility was achieved from Cu2O deposited at 300oC that equals to 11 cm2V-1s-1.
CuO metal-semiconductor-metal (MSM) Schottky photodiodes (PD) are fabricated by depositing Cu interdigitated electrodes on CuO thin films at room temperature. Photosensing properties of the CuO MSM PD are characterized from 400 ~ 1300 nm and a maximum responsivity of 43 mA/W is found at 700 nm. The photocurrent transient properties are found to be RC limited with a decay time less than 1 μs. The Schottky barrier height between Cu and CuO is 0.87 eV. These findings may serve as valuable information for the optimization of CuO based photovoltaic devices.

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