Ultra-High Responsivity Bridge Uncooled Infrared Microbolometers Based on Thin-Film Mn-Co-Ni-O

This paper introduces a novel bridge-structure process for infrared microbolometers based on thin film Mn-CoNi-O (MCN). The MCN annealing process (750 °C) after releasing polyimide (PI) is adopted to achieve process compatibility. MCN with 43-fold lower resistivity is used for reduced thermal noise. At 293 K, the temperature coefficient of resistance (TCR) of the MCN thin film is measured to be approximately -3.3 %/K. A bridge-structure design is employed to optimize the thermal conductivity to $1.3\mathrm{e}^{-4}\ \mathrm{W}/\mathrm{K}$, resulting in an enhanced responsivity of 234.7 V/W. It features ultra-high responsivity, low resistivity, high stability and large dynamic range. The findings demonstrate the significant potential of MCN for widespread application in microbolometers.