本研究主要利用固態燒結法 (solid state sintering)，製備出新穎鈷鎢氧化物靶材，並使用射頻磁控濺鍍方式以及電子束蒸鍍法，形成鈷鎢氧化物薄膜。
本研究先以不同莫耳比WO3與Co3O4混合比例製作出生胚 (green pellets)，並使用電子束蒸鍍法，沉積薄膜於玻璃基板，利用田口法設計薄膜的退火條件。從四點探針量測結果得知，在0.79 ≤ Co atomic ratio < 0.90成分區間內，薄膜的電阻率範圍落在100 (Ω·cm) ~ 102 (Ω·cm)。利用紫外/可見光吸收光譜分析，發現Co0.86W0.14Ox的吸收係數更達到105 cm-1，直接能隙在1.47 ~ 1.49 eV及2.38 eV，從X光繞射也發現Co0.86W0.14Ox的結構為Co3O4結構。驗證出Co0.86W0.14Ox的蒸鍍薄膜為一相當具有潛力的光吸收媒介。
本研究亦依據Co0.86W0.14Ox蒸鍍薄膜成分比例，製作出鈷鎢氧化物濺鍍靶材，其未經退火之濺鍍薄膜電阻率 = 2.25 (Ω·cm)，濺鍍薄膜之電阻率會隨著退火溫度上升而增加，在退火溫度400 °C下，電阻率 = 103 (Ω·cm)。利用紫外光光譜分析亦得知未經退火濺鍍薄膜，其費米能階為4.72 eV ~ 4.92 eV，價帶位置為5.37 eV ~ 5.79 eV，且費米能階在mid-gap附近。最後本研究亦製備出以鈷鎢氧化物為吸收層之P-I-N太陽能電池，從J-V curve可以發現，元件照光之後有光電流的產生，顯示鈷鎢氧化物薄膜是具有潛力應用於太陽能電池之氧化物吸收層材料。

In this work, the novel cobalt tungsten oxide sputter target was fabricated by solid state sintering, and its thin film depoisted by E-beam deposition and RF-sputtering.
Green pellets as source for E-beam deposition will be fabricated by mixing the different molar ratio of WO3 and Co3O4 oxide powder, and thin film was deposited on the glass substrate. The annealing conditions for thin film deposited by E-beam was designed from Taguchi method. The resuls from four point probe measurement showed that the resistivity of thin films ranged from 100 ~102 (·cm) when the Co atomic ratio in thin films measured by EDX (energy dispersive spectrometer) were in the range of 0.79≤Co atomic ratio<0.90. The optical properties were characterized by UV-Vis spectrum, the results showed that the absorption coefficient for Co0.86W0.14Ox thin film was up to 105 cm-1; moreover, the direct band-gaps were 1.47~1.49 eV and 2.38 eV. The crystal structure detected by X-ray diffraction also revealed that the possible structure of Co0.86W0.14Ox thin film was Co3O4. According to the above analysis, it suggested that Co0.86W0.14Ox thin film deposited by E-beam could serve as a light harvesting agent.
Thus, the novel cobalt tungsten oxide sputter target based on the composition of Co0.86W0.14Ox thin film was fabricated. The resistivity of as-deposited sputtered thin film was 2.25 (Ω·cm), and the resistivity increased with higher annealing temperature. Under 400 °C annealing temperature, the resistivity of thin film was up to 103 (Ω·cm). Fermi level and the conduction band of as-deposited sputtered thin films were characterized by UPS, the results showed that the fermi level and conduction band were at 4.72 eV ~ 4.92 eV and 5.37 eV ~ 5.79 eVrespectively, meaning that fermi level was nearby the midgap. Finally, the cobalt tungsten oxide thin film depoisted by RF-sputter as absorption layer in P-I-N solar cell was fabricated. From J-V curve measruemt, there was photocurrent ocurred under illumination, strongly suggesting that the cobalt tungsten oxide thin film would be the promising absorption material for futuer photovoltaic applications.

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