Low-loss CPW on low-resistivity Si substrates with a micromachined polyimide interface layer for RFIC interconnects
- 1 May 2001
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Microwave Theory and Techniques
- Vol. 49 (5) , 866-870
- https://doi.org/10.1109/22.920142
Abstract
The measured and calculated propagation constant of coplanar waveguide (CPW) on low-resistivity silicon (1 /spl Omega//spl middot/cm) with a micromachined polyimide interface layer is presented in this paper. With this new structure, the attenuation (decibels per centimeter) of narrow CPW lines on low-resistivity silicon is comparable to the attenuation of narrow CPW lines on high-resistivity silicon. To achieve these results, a 20-/spl mu/m-thick polyimide interface layer is used between the CPW and the Si substrate with the polyimide etched from the CPW slots. Only a single thin-film metal layer is used in this paper, but the technology supports multiple thick metal layers that will further lower the attenuation. These new micromachined CPW lines have a measured effective permittivity of 1.3. Design rules are presented from measured characteristics and finite-element method analysis to estimate the required polyimide thickness for a given CPW geometry.Keywords
This publication has 14 references indexed in Scilit:
- 50-GHz interconnect design in standard silicon technologyPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- A measurement-based design equation for the attenuation of MMIC-compatible coplanar waveguidesIEEE Transactions on Microwave Theory and Techniques, 1999
- Si-micromachined coplanar waveguides for use in high-frequency circuitsIEEE Transactions on Microwave Theory and Techniques, 1998
- Characterization of thin film microstrip lines on polyimideIEEE Transactions on Components, Packaging, and Manufacturing Technology: Part B, 1998
- Micromachined microwave transmission lines in CMOS technologyIEEE Transactions on Microwave Theory and Techniques, 1997
- Recent advances with SiGe heterojunction bipolar transistorsThin Solid Films, 1997
- L-band internally matched Si-MMIC front-endIEEE Transactions on Microwave Theory and Techniques, 1996
- High performance microshield line componentsIEEE Transactions on Microwave Theory and Techniques, 1995
- Comparison of On-Wafer CalibrationsPublished by Institute of Electrical and Electronics Engineers (IEEE) ,1991
- Precise Millimeter-Wave Measurements of Complex Refractive Index, Complex Dielectric Permittivity and Loss Tangent of GaAs, Si, SiO/sub 2/, A1/sub 2/O/sub 3/, BeO, Macor, and GlassIEEE Transactions on Microwave Theory and Techniques, 1983