Performance-Enhanced CMOS Polysilicon Microbolometer with Narrow Supporting Arms

The performance of a microbolometer can be significantly impacted by the structure of its supporting arms. In this study, we successfully enhanced the performance of a CMOS microbolometer by reducing the width of its supporting arms through a post-CMOS process. The microbolometer with
$3\ \mu \mathrm{m}$
L-type supporting arms demonstrates an ultra-low thermal conductance of
$1.26\times 10^{-7}\mathrm{W}/\mathrm{K}$
and a maximum responsivity (
$R_{\mathrm{v}}$
) of about
$3.96\times 10^{4}\mathrm{V}/\mathrm{W}$
at
$25\ \mu \mathrm{A}$
. The average responsivity of the microbolometer is improved by 66.2% from
$7 \mu\mathrm{m}$
to
$13\ \mu \mathrm{m}$
compared to the microbolometer with
$5\ \mu \mathrm{m}$
supporting arms. The demonstrated high-performance CMOS microbolometer with narrow supporting arms holds a simple structure and preparation process, which is promising for high-density array integration.