A Highly Sensitive Bolometer Structure With an Electrostatic-Actuated Signal Bridge

A novel bolometer structure has been proposed to achieve high detectivity. The detectivity is inversely proportional to the thermal conductance of a bolometer, and most of the thermal conductance is due to a metal wire, the placement of which is necessary for the reading of a signal. However, the thermal conductance of the proposed bolometer was unaffected by the thermal conductance of a metal wire. This is because a movable signal bridge was employed to lower the thermal conductance, thereby yielding a thermal conductance of
$hbox4.13 times hbox10^-8 hboxW/K$
. A measured detectivity of up to
$hbox4.23 times hbox10^9 hboxcm cdot hboxHz^1/2/hboxW$
was attained at room temperature.