Research on the Micro-cantilever Thermal Infrared Detector with Carbon Nanotubes
In this essay, a novel uncooled thermal tri-layer Si/Al/CNTs micro-cantilever infrared(IR) detector is designed using integrated circuit(IC) and micro-mechanical processing technology. So far for the uncooled MEMS thermal IR detectors, the sensitive parts are built at the structure of the MEMS to improve the effect of the thermal insulation. The intensity of the infrared radiation is measured by the variation of the electrical parameter of the sensitive part. The IR detector studied in this essay is different from the general detectors. In this new detector, the micro-cantilever is used as the sensitive part and its mechanical response rather than the electrical response is responsible for the detection. The micro-cantilever bends in response to incident IR thermal radiation due to the bi-material effect caused by the different thermal expansion coefficient between Si and Al. By diffusing the Si-based semiconductor piezoresistance the bending of micro-cantilever is detected to measure infrared radiation. Simultaneously by use of the temperature sensitivity of semiconductor resistance and the semiconductor piezoresistance, the same oriented change will happen owing to the temperature variation and the piezoresistive effect with the proper diffusion type, diffusion concentration and the crystal direction. Therefore, the micro-cantilever detectors have the advantages of the bolometers. Meanwhile the carbon nanotubes (CNTs) thermal absorbing layer is coated in order to enhance the IR absorption. This micro-cantilever IR detector with CNTs film adopts the new nano-material, carbon nanotubes film, as the absorbing layer, which has the high absorbing ability for infrared radiation and good characteristics in mechanics and heat. The experiment verifies that the sensitivity in this resolution is increased by about 10％.
MEMS micro-cantilever thermalinfrared detector carbon nanontubes
LIANG Jintao ZHANG Hongbing WANG Wenjun WANG Yangli
Engineering College of Armed Police Force Xian, 710086, P. R. China
国际会议
北京
英文
2007-08-05（万方平台首次上网日期，不代表论文的发表时间）