衬底温度对SnO_2薄膜中激光感生电压效应的影响  

Influence of Substrate Temperature on the Laser-Induced Voltage Effect in SnO_2 Thin Films

作　　者：周小芳[1] 张辉[2] 张鹏翔[2] 

机构地区：[1]长治学院电子信息与物理系,山西长治046011 [2]昆明理工大学光电子新材料研究所,云南昆明650051

出　　处：《激光与光电子学进展》2012年第1期156-160,共5页Laser & Optoelectronics Progress

基　　金：山西省高校科技研究开发项目(20111027)资助课题

摘　　要：采用固相反应法制备了四方相结构的SnO2靶材,选用蓝宝石衬底,利用脉冲激光沉积法在不同温度下生长了一系列SnO2薄膜。X射线衍射测试结果表明,SnO2薄膜具有四方金红石结构,并且沿a轴近外延生长。另外,在倾斜衬底上生长的SnO2薄膜上观察到了激光感生电压(LIV)效应,并研究了衬底温度对SnO2薄膜中LIV效应的影响。结果表明,随着生长温度从500℃增加到800℃,SnO2薄膜中的LIV信号的峰值电压先增加后减小,响应时间随衬底温度的升高先降低后增加,此外,存在一个最佳的衬底温度,使得SnO2薄膜的LIV信号的峰值电压达到最大,响应时间达到最小。在生长温度为750℃的SnO2薄膜中探测到响应最快的LIV信号,在紫外脉冲激光辐照下,峰值电压约为4V,响应时间为98ns,信号的上升沿为28ns,与激光的脉宽相当。SnO2 polycrystalline target with pure tetragonal phase is synthesized by solid-state reaction, and is employed to fabricate SnO2 thin films on sapphire substrates by pulsed laser deposition technique. X-ray diffraction （XRD） analysis shows that all the films are a-oriented and present good crystalline quality. Laser-induced voltage （LIV） effect is found in those films grown on the vicinal-cut substrates, and the influence of the substrate temperature on the LIV effect in Sn02 thin films is studied. With the temperature increasing from 500 ℃ to 800 ℃, the peak voltage of LIV signals in SnO2 thin films firstly increases, and then decreases. At the same time, the response time firstly decreases, and then increases. Meanwhile, the optimal temperature is found, at which the peak voltage of LIV signals reaches the maximum. The response time and the rise time reach 98 and 28 ns, respectively, which is comparable to the duration of the applied laser pulse.

关 键 词：薄膜 激光感生电压 各向异性Seebeck系数 温度 

分 类 号：TB303[一般工业技术—材料科学与工程]