离子束增强沉积VO_2多晶薄膜的温度系数

Temperature coefficient of resistance of VO_2 polycrystalline film formed by ion beam enhanced deposition

用改进的离子束增强沉积方法和恰当的退火从V2 O5粉末直接制备了VO2 多晶薄膜 .实验测试表明 ,薄膜的取向单一、相变特性显著、结构致密、界面结合牢固、工艺性能良好 ,薄膜的电阻温度系数 (TCR)最高可达 4 2 3% K .从成膜机理出发 ,较详细地讨论了离子束增强沉积VO2 多晶薄膜的TCR高于VOx 薄膜的TCR的原因 .分析认为 ,单一取向的VO2 结构使薄膜晶粒具有较高的电导激活能 ,致密的薄膜结构减少了氧空位和晶界宽度 ,使离子束增强沉积VO2 多晶薄膜结构比其他方法制备的VOx 薄膜更接近于单晶VO2

The polycrystalline VO 2 film was directly prepared from V 2O 5 powder using the modified ion beam enhanced deposition (IBED) method and a suitable annealing. Testing results show that the IBED polycrystalline VO 2 film has a single orientation, an obvious phase transition, a compact structure, and favorable processing properties. The temperature coefficient of resistance (TCR) of the film was up to more 4% and adhered hard to the substrate. The mechanism of the IBED film with higher TCR was discussed in detail. The reason why the film has a high TCR could be as follows: the oxygen vacancy and crystalline boundary in the film was decreased due to the IBED technology; with single oriented and dense texture the activation energy of electrical conduction of the IBED polycrystalline VO 2 film was closer to the activation energy of VO 2 crystalline in semiconductor phase which is higher than that of the VO x films prepared by other methods.