Fabrication and preliminary test results of BICEP (Background Imaging of Cosmic Extragalactic Polarization) bolometer

We report the results of fabrication and testing for the world's most sensitive MEMS bolometer. Our bolometer is designed to map temperature gradients within the cosmic microwave background (CMB). The bolometer is capable of differentiating temperature differences in the CMB that are less than 10 parts per million. The key to this ultrahigh sensitivity is the "spider web" architecture fabricated from a suspended, metallized silicon nitride film. We report the results of fabrication and characterization of a novel spider web bolometer, the so-called BICEP (Background Imaging of Cosmic Extragalactic Polarization), capable of detecting the polarization as well as the intensity of the incident microwave radiation. The bolometer was characterized over a range of sub-Kelvin ambient temperatures. We report the results of the voltage response, time constant, and the "leakage" in the bolometer's responsivity to incident microwave polarizations. Finally, from our experimental results we have determined that the bolometer has a low noise equivalent power of 2-10/sup -17/W/Hz/sup - 1/2 /.