Study of carbon nanotube based terahertz detectors

Terahertz (0.3∼10THz) technologies have been proven to be useful in many areas. There is significant push in miniaturization of THz systems and components especially detectors since they are the key components. However, low-cost large-area compatible detector fabrication is difficult to achieve.;In this thesis, a CNTs Schottky diode THz detector featured with low-cost large area compatibility is simulated and fabricated.;Simulations are carried out that considers critical parameters. To overcome huge impedance mismatch between antenna and CNT Schottky diode, multi-CNTs aligned devices were simulated and analyzed. The simulation results show that NEP of approximately 5.5pW/Hz0.5 or better can be achieved.;For realizing low-cost large area processing of such device, organic polymer substrates were studied and down selected. Furthermore, an effective novel nano-fabrication process was first developed to avoid using e-beam lithography. Device critical gap sizes of 1µm or smaller have been demonstrated using this process.;Measurements results showed strong non-linear rectifying behavior and NEP of 61.3 and 111pW/Hz0.5 at 18GHz and 1THz. Those can be decreased by using higher quality and optimized numbers of CNTs in a single device.