具熱致變特性之V1-x-yWxSiyO2複合薄膜因有較高的電阻溫度係數,所以是應用在非冷卻型輻射熱感測器元件的重要熱敏電阻材料之一。在本論文中,以溶膠凝膠法及旋轉塗佈法製備V1-x-yWxSiyO2複合薄膜,經由還原氣氛爐在500℃~600℃條件下煅燒成V1-x-yWxSiyO2 複合薄膜。除此之外,V1-x-yWxSiyO2 複合薄膜再利用黃光製程製備成非冷卻型輻射熱感測器元件。 將所製備 V1-x-yWxSiyO2複合薄膜分別藉由四點探針量測儀檢測在不同溫度條件下其電性性質的改變及原子力顯微鏡檢測其表面分佈型態與晶粒大小。除此之外,利用半導體製程將高電阻溫度係數的薄膜做成非冷卻型輻射熱感測器元件;提供其元件直流電源且並聯一個電阻,在500K的黑體模擬器輻射下利用鎖像放大器及截波器檢測在不同頻率條件下元件應答及雜訊。 研究結果顯示V1-x-yWxSiyO2複合薄膜相轉變溫度可由70℃改質到20℃,且在室溫,電阻溫度係數可達11%/K。當複合薄膜摻雜莫耳比(Wx+/V4+)0.02,可得到一對線性的遲滯迴圈;摻雜莫耳比(Siy+/V4+)0.15可得一對窄頻寬的遲滯迴圈。除此之外,在不同的摻雜量與操作條件下,都可得到高再現性的熱電性質。在非冷卻型輻射熱感測器元件優質係數檢測方面,其研究結果顯示,電壓響應在截波頻率60Hz達到最大值2600V/W;感應度最大值為9*106 cm Hz1/2 /W。
TheV1-x-yWxSiyO2 composite thin films are thermochromic materials for the uncooled microbolometer due to their high temperature coefficient of resistance (TCR) at room temperature. In this study, V1-x-yWxSiyO2 thin films were prepared by sol-gel method followed by spin coating process, and then calcined at 500℃~600℃ under a reducing gas flow in an atmospheric control furnace. The bolometers are patterned by photolithography process followed by wet etching. The electrical properties of the thin films were measured by a 4-point probe meter. The surface morphology was obtained by AFM. In addition, the ohmic contact V1-x-yWxSiyO2 composite thin films were fabricated as bolometers by sputtering process; the bolometer is connected with a DC source and loaded a resistance equal to the resistance of bolometer, and the bolometer is exposed to a filtered radiation of a 500K black body to measure its responsivity and noise. The open circuit voltage is measured using a lock-in amplifier modulated by a chopper and the incident radiation. The V1-x-yWxSiyO2 composite thin films characterized a switching temperature ranging from 20℃ to 70℃, accompanied with a temperature coefficient of resistance (TCR) 11%/K at room temperature. The composite films doped with tungsten at mixing ratio (Wx+/V4+) of 0.02 show a sharp hysteresis loop, whereas the composite films doped with silicon at mixing ratio (Siy+/V4+) of 0.15 has a tight bandwidth of hysteresis loop. A variety of thermal-optical characteristics can be achieved with various dopant concentrations and process conditions. Figures of merit for composite thin films were further evaluated on the one-element bolometers without air-gap suspending structure. Results show that the detectors exhibit a responsivity over 2600 V/W and detectivity 9*106 cm Hz1/2 /W at 60Hz chopper frequency measured at room temperature.