A novel slow-wave structure for millimeter-wave filter application on bulk CMOS

Abstract

A novel slow-wave structure for microstrip lines is proposed. Unlike conventional slow-wave structures such as photonic bandgap (PBG) and ladder microstrip lines, which only deal with the substrate, ground plane or the signal line of a microstrip separately, the periodic patterns of this new slow-wave structure are etched in both the conductive metal strip and the ground plane of the proposed microstrip line. No extra drilling through the substrate is required. The designed slow-wave structure exhibits that size reduction and minimal loss increase can be achieved simultaneously. 2ndorder rectangular open-loop filters with and without implementing the proposed slow-wave structure have been designed and fabricated in the millimeter-wave (mm-wave) range on 65-nm bulk CMOS. Both simulations and measurements demonstrate the new design has a 52.7% size reduction with only 0.5 dB penalty in transmission loss. To author's best knowledge this compact filter is the first reported mm-wave filter using slow-wave structure on bulk CMOS. Index Terms -CMOS, filter, microstrip, millimeter wave, (photonic bandgap) PBG, slow-wave, 60 GHz. 1. The passband was measured with 1-dB bandwidth. 2. The passband was measured when the return loss is better than 15 dB. 3. The passband was measured with 3-dB bandwidth. 4. The passband was measured with 5-dB bandwidth.

Slow-wave microstrip line on nanowire-based alumina membrane

“…It is possible, though, to increase Gre ff and create the slow-wave effect by different approaches, such as performing geometrical modifications on microstrip lines [4], or adding a shielding plane to CPW (S-CPW) [5]. In this context, to our knowledge, the S-CPWs show the highest Gre ff presented so far.…”

Holistic design strategy for high‐selectivity low‐loss integrated millimetre‐wave image‐reject filters

“…Waveguide-type filters typically have low insertion loss and high selectivity but they are bulky. On the other hand, on-chip planar filters [7][8][9][10][11][12][13][14][15][16][17][18][19][20] offer more compact solution but they are lossy particularly when realised in low-resistivity substrate technology. For example, in [21], a third-order band-pass filter designed at 9.45 GHz and realised in 130 nm complementary metal-oxide semiconductor (CMOS) technology exhibited a rather high insertion loss of 15.6 dB.…”

Modeling and Characterization of Slow-Wave Microstrip Lines on Metallic-Nanowire- Filled-Membrane Substrate

“…Considerable effort has being invested on the development of high-performance slow-wave (SW) structures in different technologies in order to reduce the area of the lambda-based devices. In CMOS, slow-wave transmission lines (SWTLs) using the metallic interconnections of the back-end-of-line have been successfully demonstrated in [1]- [4] based on coplanar waveguide (CPW) technology, or in [5], based on microstrip transmission lines. An electrical model of slow-wave coplanar waveguide (S-CPW) was proposed A.-L. Franc in [6].…”