Abstract:
Uncooled IR (infrared) microbolometer performance is greatly affected by the thermal
properties associated with the structural layout of each design. Equations are derived in this article
which make use of basic structural dimensions to predict the expected thermal conductance and
thermal capacitance of a microbolometer device. These equations enable a microbolometer designer
to determine the estimated thermal time constant of a design without performing complicated analytical
calculations for each layer in the design. Calculation results shown indicate the effect structural changes
have on the thermal time constant of microbolometer devices. These changes aid microbolometer
designers in adjusting the layout of the device to change the thermal time constant to the desired
value. Structural deviations that occur during manufacturing of microbolometers are calculated and
the possible causes are discussed.
