A compact integrated band-pass filter on a low-dielectric constant polyimide dry film
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A new compact integrated tapped-line combline filter, with metal-insulator-metal (MIM)-type capacitive loads, is designed and fabricated using newly proposed micromachining techniques that employ a polyimide dry film as a dielectric layer. For increased uniformity of thickness, a dry-film fabrication process is developed. The presented filter is realized with a relatively small size, 3.68 by 4.53 mm, on a polyimide dry film and shows up to 50% size reduction as compared with a general quarter-wavelength filter.