Modelling of a Novel Micro Scaled THz Detector
Examensarbete för masterexamen
In order to extend technology into THz part of electromagnetic wave spectrum THz detectors are required. So far THz detectors have been used in astronomical observations with state of the art sensitivity requirements. To achieve the required sensitivity super conducting technology are used (temperatures below 5K). These detectors require the cryogenic temperature and lack portability and ease of operation. Since interest of more conventional applications, such as THz robotic vision, THz security scanners, etc., has grown over the years and the rapid progress in micro-machining and micro scaling technology, it is now possible to build THz detectors, which operate at room temperature and are small enough. The motivation for this thesis is to model and design a new micro-scaled THz detector. The detector dimensions are first to be estimated theoretically and then the various physics involved is to be investigated with RF and multi-physics simulations. The task is to design a detector, which is able to detect terahertz radiation at frequencies between 0.5-5 THz; this is a very broad banded detector which will impose certain restrictions on the system. In this thesis innovative designs were developed in order to overcome critical issues, such as maximizing absorption over a broadband and at the same time minimize the volume. The designs were successfully simulated with professional programs at room temperature for a frequency range of 0.5-5 THz. The design were optimized and robust design parameter values were suggested, which give a relative output signal difference of 13.5% ± 1% over the whole frequency range at 2 μW. Furthermore, the relationship between the relative capacitance difference and input power clearly displays power function behavior. Further study also show that the change in output signal with respect to input power exhibit linearity at input powers higher than 10 μW and input powers less than 2 μW. The detector should therefore be biased with in of 2-8 μW for high sensitivity.
Numerisk analys , Matematisk statistik , Optik , Halvledarfysik , Struktur- och vibrationsfysik , Statistisk fysik , Övrig elektroteknik, elektronik och fotonik , Övrig teknisk fysik , Numerical analysis , Mathematical statistics , Optics , Semiconductor physics , Structural and vibration physics , Statistical physics , Other electrical engineering, electronics and photonics , Other engineering physics