本實驗使用反應式離子束共濺鍍Zn及Mg金屬靶沉積MgxZn1-xO薄膜，利用不同離子束電流調整x = 0 ~ 0.46，薄膜沉積於Si (100)、玻璃及石英基板。XRD量測結果中，MgxZn1-xO薄膜退火前或退火後隨著x提升a軸長度逐漸增加，而晶粒尺寸減少，當x > 0.40出現立方結構。PL光譜中可知退火後MgxZn1-xO薄膜放射峰能量由3.26 (x = 0) 增加至3.52 eV (x = 0.46)，薄膜未退火前表面平整，而退火後薄膜表面平整度下降。由穿透率量測MgxZn1-xO薄膜之光學能隙，可由3.28 (x = 0) 提升至4.36 (x = 0.46) eV。MgxZn1-xO薄膜沉積時通入氮氣，或薄膜沉積後於氮氣氛下退火，皆可改善薄膜之電特性，含氮Mg0.03Zn0.97O薄膜退火後載子濃度較高、電阻率較低、載子遷移率高，電性較其他薄膜佳，較適合應用於元件製作。最佳含氮MgxZn1-xO薄膜所製備完成之光檢測器其鑑別率 (RUV/Rvisible) 可達1個數量級。

MgxZn1-xO thin films with x = 0 ~ 0.46 has been deposited on Si (100), glass and quartz substrates by reactive dual ion beam sputtering deposition. XRD analysis shows that as x increases, a-axis lattice constant increases while the grain size decreases. As x reaches 0.40, the cubic phase becomes discernable. PL study of MgxZn1-xO thin films shows emission energy varying from 3.26 (x = 0) to 3.52 eV (x = 0.46). The blueshift of emission energy is attributed to Mg atoms replacing Zn atoms that lead to increased bandgap. The optical bnadgap of MgxZn1-xO thin film increases from 3.36 to 4.36 eV as x increases from 0 to 0.46. The electrical properties of MgxZn1-xO can be improved by doping witn nitrogen or annealing in nitrogen ambient. Under optimized conditions, the rejection ratio of photodetectors fabricated by nitrogen doped MgxZn1-xO exhibit a rejection ratio of ~ 10.

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