X-ray microfabrication and measurement of a terahertz mode converter

T. H. Chang, B. Y. Shew, C. Y. Wu, N. C. Chen
2010 Review of Scientific Instruments  
Mode converters are critical for frequency-tunable terahertz gyrotrons. This study reports the development of a broadband TE 02 mode converter centered at 0.2 THz. An octafeed sidewall coupling structure was employed and the mode purity was analyzed. The converter was built using the technique of x-ray microfabrication. The x rays irradiated on the SU-8 resist and generated a template of very high thickness of 1.295 mm. Pulse electroplating technique was used to deposit copper on the structure
more » ... r on the structure along the template. The parts then went through precise machining and the residual resist was removed via high-flux radical etching. A computer-aided diagnostic system was introduced to measure the performance of the converter. Results suggest that the frequency response of resistivity should be taken into consideration for the devices in terahertz region.
doi:10.1063/1.3385685 pmid:20515160 fatcat:76gvz7b2avd65d6th3eax3z3nq