摘要
重掺杂多晶硅纳米薄膜具有良好的压阻温度特性,用它制作高温压阻式传感器灵敏度高、成本低,具有广阔的应用前景.为优化多晶硅纳米薄膜的压阻温度特性,本文采用低压化学气相淀积(LPCVD)技术制作了不同膜厚(30～250 nm)的多晶硅薄膜,分别测试了应变系数、薄膜电阻率与工作温度的关系.利用扫描电镜(SEM)和X射线衍射实验(XRD)对薄膜进行了表征,在此基础上结合隧道压阻模型分析了膜厚对多晶硅薄膜压阻温度特性的影响,结果表明,对于淀积温度620℃、掺杂浓度2.3×1020 cm-3的多晶硅纳米薄膜,膜厚的最佳值在80 nm厚左右.
Heavy doped polysilicon nanofilms have good piezoresistive temperature properties,and high temperature piezoresistive sensors made of them,which have high sensitivity,low costs enjoy a broad application prospect. To optimize the piezoresistive temperature properties,low pressure chemical vapor deposited(LPCVD) polysilicon films of different thickness(30~250 nm)were made,and the relationship between gauge factor,resistance of films and testing temperature were tested.The microstructure of films was observed by the means of scanning electron microscope(SEM) and X-ray diffraction(XRD).Based on the tunneling piezoresistive model,the influence of thickness on piezoresistive temperature properties of polysilicon nanofilms was analyzed.The results indicate that for polysilicon nanofilms deposited at 620℃,with doping concentration of 2.3×1020 cm-3,the best value of thickness should be around 80 nm.
出处
《传感技术学报》
CAS
CSCD
北大核心
2007年第11期2421-2425,共5页
Chinese Journal of Sensors and Actuators
