磁控溅射结合快速热处理制备相变氧化钒薄膜

采用直流对靶磁控溅射结合快速热处理工艺制备了具有金属-半导体相变特性的氧化钒(VOx)薄膜。利用XRD,XPS和SEM对薄膜结晶结构、薄膜中V的价态与组分及表面微观形貌进行分析,利用四探针测试法及太赫兹时域频谱系统对薄膜的电学和光学特性进行测量。结果表明:新制备VOx薄膜以非晶态V2O5为主;350℃,30 s快速热处理后,薄膜中V的整体价态降低,表面颗粒分布更加致密;500℃,30 s快速热处理后,薄膜中VO2(002)向单斜结构的VO2(011)转变,VO2(011)占主要成分,薄膜显示出明显的金属-半导体相变特性,方块电阻下降达到3个数量级,太赫兹透过率下降接近70%,热致相变性能良好。

Preparation of Phase Transition Vanadium Oxide Thin Films by Magnetron Sputtering with Rapid Thermal Process

The VOx thin film with metal-semiconductor phase transition characteristic was prepared by reactive direct current facing targets magnetron sputtering with rapid thermal process.The film crystal structure,valence state and composition of vanadium and surface morphology were analyzed by XRD,XPS and SEM.The electrical and optical properties of the films were measured by the four-point probe method and terahertz time domain spectroscopy.The results show that the as-deposited VOx thin films are mainly composed of non-crystalline V2O5.After annealing 30 s at 350 ℃,the overall valence of vanadium decreases and the surface particle distribution are more compact.After annealing 30 s at 500 ℃,VO2(002) changes to VO2(011) which appears as monoclinic structure,and VO2(011) is the main component.The VOx films show a good metal-semiconductor phase transition characteristic,the sheet resistance decreases 3 magnitude orders,and the THz transmittance reduces about 70%,the thermal phase transition characteristic is perfect.