Improving the reliability of carbon nanotube based infrared sensors

In this paper, a reliable and stable carbon nanotube based infrared photodetector was proposed. It was not only for the fundamental understanding of CNT photoresponse induced processes, but also for the development of a new infrared sensitive material with unique optical and conductivity features. The temperature and humidity changes would dominate sensor response in nanoscale materials. In the proposed design, the sandwich-structured sensor was fabricated within two polymer layers. The substrate polyimide provided sensor with high bending stiffness, and top parylene packing blocked humidity environmental issues. At the same time, the fabrication process was optimized by real time electrical detection dielectrophoresis and multiple annealing to improving fabrication yield and sensor performance. In order to make measurements under same condition, a digital microscope and precise linear stage based measurement system was introduced. The experimental results showed that the photodetectors had more uniformities and stable photoresponse.