Nanoscale Bolometry: Pushing Sensitivity Limits of Uncooled Infrared Thermal Detectors

Resistive bolometers are devices that change resistance in response to a change in temperature. Often, they are used in the thermal detection of infrared radiation through the incorporation of an absorbing film that transduces absorbed light into a rise in temperature. The performance of these devices may be quantified by specific detectivity, which is fundamentally limited by how well the device is radiatively coupled to its environment. In this presentation, we discuss experimental efforts toward the realization of an uncooled bolometer with performance approaching the theoretical limit of detectivity. Among these efforts, we highlight advancements in the development of critical device elements including high-efficiency, ultra-thin absorber and thermometer films. In addition, we discuss a nanofabrication method to suppress thermal conductance due to conduction and enhance the radiant heat exchange of the system.