Uncooled bimaterial cantilever for infrared detection based on resonant frequency tracking

A novel method of detecting infrared (IR) radiation by tracking resonant frequency of bimaterial resonant sensors is presented. A capacitive bimaterial resonant sensor (BRS) array consisting of 6×6 cells is fabricated by surface sacrificial layer process. The BRSs are packaged and tested not only by optical but also by electrical method. The results indicate that the BRSs exhibit a monotonic frequency response, which is in correspondence with the theoretical prediction by finite element method. The resonant frequency responsivity of the BRS is better than 363×Hz×K by electrical measurement.