WR-3 waveguide bandpass filters fabricated using high precision CNC machining and SU-8 photoresist technology

Yang, H., Dhayalan, Y., Shang, X., Lancaster, M. J., Liu, B. , Wang, H., Henry, M. and Huggard, P. G. (2018) WR-3 waveguide bandpass filters fabricated using high precision CNC machining and SU-8 photoresist technology. IEEE Transactions on Terahertz Science and Technology, 8(1), pp. 100-107. (doi: 10.1109/TTHZ.2017.2775441)

Abstract

This paper presents two WR-3 band (220-325 GHz) filters, one fabricated in metal using high precision computer numerically controlled milling and the other made with metallized SU-8 photoresist technology. Both are based on three coupled resonators, and are designed for a 287.3-295.9-GHz passband, and a 30-dB rejection between 317.7 and 325.9 GHz. The first filter is an extracted pole filter coupled by irises, and is precision milled using the split-block approach. The second filter is composed of three silver-coated SU-8 layers, each 432 μm thick. The filter structures are specially chosen to take advantage of the fabrication processes. When fabrication tolerances are accounted for, very good agreement between measurements and simulations are obtained, with median passband insertion losses of 0.41 and 0.45 dB for the metal and SU-8 devices, respectively. These two filters are potential replacements of frequency selective surface filters used in heterodyne radiometers for unwanted sideband rejection.

• Item Type: Articles
• Additional Information: This work was supported by the U.K. Engineering and Physical Science Research Council under Contract EP/M016269/1.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Liu, Dr Bo
• Authors: Yang, H., Dhayalan, Y., Shang, X., Lancaster, M. J., Liu, B., Wang, H., Henry, M., and Huggard, P. G.
• College/School: College of Science and Engineering > School of Engineering
• Journal Name: IEEE Transactions on Terahertz Science and Technology
• Publisher: IEEE
• ISSN: 2156-342X
• ISSN (Online): 2156-3446
• Published Online: 07 December 2017
• Copyright Holders: Copyright © 2017 IEEE
• First Published: First published in IEEE Transactions on Terahertz Science and Technology 8(1): 100-107
• Publisher Policy: Reproduced under a Creative Commons License