| Popis: |
Thermal detectors have been gaining a lot of attention because their operation is independent of wavelength and bandgap limitations. Thermal detectors are seen as viable candidates capable of long wavelength detection specifically where conventional semiconductor photodetectors fail to provide room-temperature high responsivities in the field of optical astronomy, space exploration study, satellite imaging, 3D sensing, and LiDAR based automobile safety systems. Previously, metallic films such as Nickel, Bismuth, Platinum, and Nickel-Chromium, have been studied as possible radiation sensing materials for bolometer thermal detectors. So far, the metallic film bolometer thermal detectors have been struggling with thermal mass and heat dissipation.The objective of this dissertation is to establish room temperature thin film linear array bolometer devices as thermal detectors. A large % TCR near room-temperature is achieved for both Nickel and Bismuth thin films. The large % TCR is responsible for achieving room-temperature high responsivity of 0.11 V/W for Bismuth thin film linear array bolometer thermal detectors. This dissertation reports the first demonstration of an enhancement in room temperature responsivities of thin film linear array bolometer devices achieved by a novel heterostructure radiation sensing layer of Carbon Nitride thin films over the Nickel and Bismuth thin films. A higher responsivity of 0.14 V/W is achieved at room temperature operation with a much-reduced thermal time constant of 142 ms for the heterostructure radiation sensing layer of Carbon Nitride films over the Nickel thin film for the thin film linear array bolometer devices.Thus, through this dissertation, it is demonstrated that Carbon Nitride thin film linear array bolometer devices as thermal detectors can achieve higher room temperature responsivities by overcoming the current limitations of thermal noise, thermal mass, and heat dissipation. These results also establish that thin film linear array bolometer thermal detectors are compatible with the modern MEMS fabrication processing for optical astronomy, 3D sensing, and LiDAR based applications. |
