A MEMS Thermopile with Al Decorated Nanoforests Capable of Broadband UV Detection

This work presents a MEMS thermopile integrated with Al nanoparticle-decorated nanoforests (Al@NFs), fabricated using a CMOS compatible process. Due to the light trapping effect and the localized surface plasmon resonance effect introduced by the Al@NFs, ultraviolet (UV) optical energy can be effectively absorbed and converted into heat energy. As a result, a broad UV detection range of the device is achieved. Compared with the pristine thermopile without such Al@NFs, the voltage response of the device is improved by 2.0 to 16.2 times within a wavelength range of 240–400 nm. With such a superiority, the as-prepared device is capable of UV detection for practical applications, including the quality discrimination of different sunscreens under UV radiation.