Grid‐Shaped, Vertically Aligned Carbon Nanotube Architectures for Electrical, Optical, and Mechanical Bolometers

ABSTRACT Grid‐shaped, vertically aligned carbon nanotube (VACNT) architectures demonstrate excellent broadband photothermal conversion of 1°C at 0.17 W cm − 2 , small thermal mass for response time of less than 0.1 ms, and a high mechanical bending capacity. This expands the range of applications for traditional membrane‐ and cantilever‐based microelectromechanical systems. Their small geometries, down to 3 × 3 µm 2 , and cost‐effective fabrication make them ideal for the reliable, large‐scale integration of sensor arrays, even for single‐use biomedical, industrial and security applications. We present three proof‐of‐concept experiments for innovative room‐temperature bolometer pixels with integrated thermoresistive, thermochromic, and thermomechanical transducers. These allow the efficient conversion of ultraviolet (UV) to the terahertz (THz) spectrum into thermal, and subsequently into electrical or optical output signals. The optical and mechanical bolometers contain thermochromic or thermomechanical microspheres within the VACNT grid, enabling the creation of bias‐free, contactless thermal detectors with the potential to achieve thermal phonon‐limited performance. These architectures feature simple, integrated electrical and optical readout technologies and will also deliver high performance in response to other physical or biological stimuli in the near future. They will open up a broader range of applications in areas such as mid‐IR spectroscopy and miniaturized, cantilever‐like bioanalytical devices.