本研究利用電子槍蒸鍍製程，並配合後退火與氧化程序，成長 Cu-Sn-Mn-O多元氧化物薄膜，並以此應用於光電化學電池與降解有機物之領域。
本研究選用CuO、SnO2、MnO2等地球含量豐富的氧化物，透過不同成份比例之調配，由UV-Vis之量測結果，得到在光波長為400 nm至 700 nm之吸收係數高於104 cm-1的薄膜，接著進行PL、CL、UPS分析，得知薄膜能隙約在2.3 eV，而價帶、導帶之能階位置約在6.7 eV及4.4 eV。本研究透過霍爾效應量測，得知經後退火與氧化程序之薄膜的載子濃度，可被降低到1019 至1021cm-3。透過GIXRD之晶體結構分析得知，此多元氧化物薄膜屬於混和物，存在CuO、Cu2O、SnO2、MnO、Mn3O4等晶相，並以SEM觀察得知薄膜表面形貌粗糙。
本研究將靶材成份為CuO : SnO2 : MnO2 = 3 : 1 : 3，經電子束蒸鍍並以後退火與氧化程序優化過之薄膜，並經製程條件最佳化後，進行LSV (Linear sweep voltammetry)、J-t圖(光電流-時間曲線)之特性測量後，得知薄膜在可見光照射下可得0.042 mA/cm2電流密度，而在太陽光照射下，可提供近0.1 mA/cm2電流密度，但會產生衰減現象；此外，在紫外光區的降解RhB (Rhodamine B) 有機物之速率常數為1.72 x 10-3 min-1，可見光區的降解RhB有機物之速率常數為6.9 x 10-4 min-1，而可見光區的降解MO (Methyl orange) 有機物之速率常數為2.3 x 10-3 min-1；由結果可知，Cu-Sn-Mn-O薄膜在以太陽光分解水方面之應用具有潛力。

In this work, the Cu-Sn-Mn multicomponent oxide thin film deposited from earth-abundant, stable, eco-friendly compound, CuO, SnO2, MnO2, were presented. The applications as an electrode for photoelectrochemical cell and as a material for degradation pollutant were also demonstrated.
The synthesis and characterization of Cu-Sn-Mn-O thin film were investigated in this study. By controlling the composition of target, Cu-Sn-Mn-O thin films showed more than 104 cm-1 absorption coefficient in wavelength of 400 nm to 700 nm, in visible light region by UV-Vis analysis.
The thin films were further investigated by ultraviolet photoelectron spectroscopy (UPS) , photoluminescence (PL) , cathodoluminescene (CL). The Ev (valence band energy), Ec (conduction band energy) band position of thin films, deposited from target composition of Cu : Sn : Mn = 3 : 1 : 3, was characterized as 6.7 eV, 4.4 eV, respectively, and the Eg (band gap) was measured to be 2.3 eV. Carrier concentrations of Cu-Sn-Mn-O thin films could be reduced between 1019 to 1021 cm-3 after annealing and oxidation process. By grazing incident X-ray diffractometer (GIXRD) analyses, Cu-Sn-Mn-O thin film verified as a composite containing CuO, Cu2O, SnO2, MnO, and Mn3O4.
The solar energy applications were investigated by JSV (linear sweep voltammetry), J-t (photocurrent-time curve), and photodegradation experimental tests. The best result showed a current density of 0.042 mA/cm2 under visible light excitation with good stability, and near 0.1 mA/cm2 under solar light excitation but lack of good stability. The rate constant of RhB degradation was 1.72 x 10-3 min-1 under 365 nm UV-light excitation, and 6.9 x 10-4 min-1 under visible light excitation. The rate constant of MO degradation was 2.3 x 10-3 min-1 under visible light excitation. The Cu-Sn-Mn-O thin films developed in this work showed the potential of water splitting under solar light.

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