Novel infrared detector based on a tunneling displacement transducer

The pneumatic infrared detector [M. J. E. Golay, Rev. Sci. Instrum. 18, 347 (1947)] uses thermal expansion of a gas to detect infrared radiation. We have designed a detector based on this principle, but which is constructed entirely from micromachined silicon, and uses an electron tunneling displacement transducer to detect the expansion of the gas. The design, fabrication, and characterization of the first prototype sensor are described. Its sensitivity is competitive with the best available uncooled infrared detectors.