Fabrication and Characteristics of Mesh Band-Pass Filters

Artikel i vetenskaplig tidskrift, 2009

Grid band-pass filters for 300-, 450-, 600-, and 750-GHz central frequencies are designed and fabricated. Copper and aluminum foil and foil-clad teflon filters were made by chemical and ion-beam etching, and an aluminum film evaporated on a kapton film was formed by the lift-off lithography. A gold layer was electrolytically applied on copper mesh filters. Characteristics of the filters were measured in the millimeter, submillimeter, and infrared (IR) ranges. Foil filters demonstrate better characteristics at lower frequencies, while filters with evaporated films have better characteristics at upper frequencies. The smallest transmission loss was 0.13 dB. For a stack consisting of four filters, this loss was 0.9 dB. The IR radiation attenuation in a 2.5- to 25-μm wavelength region was over 11 dB per filter.