基于聚酰亚胺/石墨复合衬底的快速响应MEMS柔性温度传感器

Fast Response MEMS Flexible Temperature Sensor Based on Polyimide/Graphite Composite Substrate

针对现有柔性温度传感器衬底导热慢的问题,为快速监测轴承等曲面的温度,向聚酰亚胺(PI)中掺入3wt%石墨(GR),制备高导热复合材料,得到的GR/PI复合薄膜导热率达到0.777 W·m^(-1)·K^(-1),且具有良好的绝缘性。基于微加工技术,在GR/PI复合薄膜上制备了铂薄膜柔性温度传感器,改善了其动态响应特性,响应时间达到71 ms,优于纯PI衬底上的铂薄膜温度传感器。除此之外,所制备的柔性温度传感器的线性度、灵敏度和测量重复性等电学性能均较好。将制备的柔性温度传感器用于金属轴表面的温度测量,与商用红外摄像仪对比,两者测量值差别较小(±2℃以内)。

To solve the problem of the substrate’s slow thermal conduction for flexible temperature sensors to quickly monitor the temperature of bearings and other curved surfaces, high thermal conductivity composites were prepared by doping 3wt% graphite(GR) into polyimide(PI), which reached a thermal conductivity of 0.777 W·m^(-1)·K^(-1)and had good insulation properties. Based on the microfabrication technique, Pt film flexible temperature sensor was prepared on the GR/PI composite film, and its dynamic response characteristics are improved with the response time of 71 ms, which is better than that of the Pt film flexible temperature sensor on pure PI substrate. In addition, the electrical properties such as linearity, sensitivity and measurement repeatability are good. The prepared sensor was used for temperature measurement on metal shaft surfaces, and the difference between the measured values is small(within ±2 ℃) compared with a commercial infrared camera.