多晶锗硅室温微测辐射热计线性阵列的研制

采用超高真空气相淀积系统 ( UHVCVD)制备了多晶锗硅薄膜 ( poly-Si0 .7Ge0 .3) ,研究了它的退火特性和电阻温度特性。将多晶锗硅薄膜电阻作为微测辐射热计的敏感元件 ,采用体硅微机械加工技术制作了 8× 1桥式微测辐射热计线性阵列 ,优化设计的微桥由两臂支撑 ,支撑臂的长和宽分别为 2 2 0 μm和 8μm,桥面面积为 80μm× 80μm。测试结果表明 ,在 773 K黑体源 8～ 1 4μm红外辐射下 ,调制频率为 3 0 Hz时 ,阵列中各单元的电压响应率为 6.2 3 k V/W～ 6.40 k V/W,探测率为 2 .2 4× 1 0 8cm Hz1 /2 W- 1～ 2 .3 3× 1 0 8cm Hz1 /2 W- 1 ,热响应时间为2 1 .2 ms～ 2 2 .1 ms,表明了器件具有较高的性能及较好的一致性。

Development of Linear Uncooled Microbolometer Array Made of Poly-SiGe Film

Poly-Si 0.7Ge 0.3 film is prepared by ultra high vacuum chemical vapor deposition (UHVCVD) system. The dependences of the poly-Si 0.7Ge 0.3 resistance on operation temperature and annealing temperature are investigated. Optimized structure of two-leg supported microbridge for microbolometer is designed, with a surface area of 80 μm×80 μm, a leg length of 220 μm and a leg width of 8 μm. With bulk silicon micromachining technique, an 8×1 linerar mircobolometer array based on poly-Si 0.7Ge 0.3 resistor as thermosensitive element is fabricated. The characteristics of the linear array are investigated under infrared radiation in the spectral region of 8～14 μm, with a black body temperature of 773 K. Measurements show that for pixels of the linear array, a responsivity of 6.23 kV/W～6.40 kV/W, a detectivity of 2.24×10 8 cmHz 1/2W -1～2.33×10 8 cmHz 1/2W -1 and a thermal response time of 21.2 ms～22.2 ms are achieved at a chopper frequency of 30 Hz.