Infrared Photothermal Properties Of Metal Nanostructure And Its Application

In recent years, metallic nano-structure has aroused attention in various fields. Metal nanowires as typical metal nano-structures have been applied in the field of biomedical and photoelectric devices. At present, the study of metal nanowires mainly concentrate in visible and near infrared wave band, but in the far infrared wave band, especially 8 ~ 14 mm systematic studies have not been found.This paper studies the optical and thermal properties of metal nanowires at infrared wavelengths, especially 8 ~ 14 mm. Prototype thermal detectors based on metal nanowires are designed and manufactured, which provides the theoretical and experimental basis for performance optimization and process improvement of further device.The main contents include:(1) Photothermal characteristics of nanowire are simulated and analyzed by using the field finite element software COMSOL Multiphysics. The relationship between the geometry size of nanowires and their photothermal characteristics are studied. Absorption peak position of nanowire is mainly decided by the antenna resonance effect, and absorption cross section is relative to the aspect ratio of nanowire. At the same time, materials of nanowire, ambient media, Si O2 thermal insulation layer and ground reflector also have obvious influence on the characteristics of metal nanowire.(2) The performance of thermal detector based on metal nanowire is studied and prototype devices are manufactured. Process flow and process parameters of device are explored. Parameters of lithography and coating process are optimized and some problems encountered in the process are solved.(3) The performances of the devices are tested. The results are consistent with the simulations and very excellent. At last, the current existing problems are analysed and some improvement solutions are put forward.