abstract |
A semiconductor sensor system, in particular a bolometer, includes a substrate, an electrode supported by the substrate, an absorber spaced apart from the substrate, a voltage source, and a current source. The electrode can include a mirror, or the system may include a mirror separate from the electrode. Radiation absorption efficiency of the absorber is based on a minimum gap distance between the absorber and mirror. The current source applies a DC current across the absorber structure to produce a signal indicative of radiation absorbed by the absorber structure. The voltage source powers the electrode to produce a modulated electrostatic field acting on the absorber to modulate the minimum gap distance. The electrostatic field includes a DC component to adjust the absorption efficiency, and an AC component that cyclically drives the absorber to negatively interfere with noise in the signal. |