The development status of the micro-cantilever array based un-cooled IR detectors

Almost two years after the investors in Sarcon Microsystems pulled the plug, the micro-cantilever array based un-cooled IR detector technology is again attracting more and more attention because of its low cost and high credibility. Recently a sort of IR imaging system consisting of micro-cantilever array and optical-readout device is presented. The basic approach is the same: Coat the micro-cantilevers with a bi-material. The absorption of infrared radiation causes a rise in temperature at each pixel which causes the bi-material to bend the cantilever. The resulting change in capacitance is measured by a readout IC. The main advantage of the micro-cantilever approach is that the temperature responsivity (as measured by the percent change in signal per degree) is approximately ten times as large as for VOx micro-bolometers (i.e. 20-50%/°C compared to 2-4%/°C). In this paper, we will discuss the following questions detailed: The imaging principle of the system, the optical-readout principle of the imaging system, the design and produce progress of the FPA and some influence factors and performance parameters of the system. Finally, the trends of this kind of devices will follow..