Effective high-frequency spectrum usage requires high-performance filters to have a sharp cutoff frequency and high stopband attenuation. Stepped-impedance low-pass designs achieve this function best with large ratios of high-to-low-impedance values. In high-index materials, such as Si (11.7) and GaAs (12.9), however, these high-to-low-impedance ratios are around five, thereby significantly limiting optimum filter performance. This paper characterizes the use of Si micromachining for the development of synthesized substrates, which, when utilized appropriately, can further reduce the low-impedance value or increase the high-impedance value. Both designs have demonstrated high-to-low-impedance ratios that are 1.5-2 times larger than conventional techniques.
|Number of pages||7|
|Journal||IEEE Transactions on Microwave Theory and Techniques|
|Publication status||Published - 2001 Feb|
Bibliographical noteFunding Information:
Manuscript received August 18, 1999; revised August 21, 2000. This work was supported by the Multidisciplinary University Research Initiative/Army Research Office Low Power Electronics Program under Grant DAAH04-96-1-0001 and by the National Science Foundation under Grant NSF/ECS-9996207.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Electrical and Electronic Engineering