Patterned Floating Dummy Fill for On-Chip Spiral Inductor Considering the Effect of Dummy Fill

This paper discusses the effect of dummy fills on the performance of spiral inductors. In Si-CMOS processes that use copper wire, metal dummy fills are required to prevent thickness fluctuation in the chemical mechanical polishing stage. Dummy fills have been thought to affect the wire capacitance; however, in high frequency, dummy fills also affect the wire resistance and the wire inductance due to the eddy current in dummy fills. This work evaluates the effect of the dummy fills by three-dimensional field solver and proposes a structure to suppress the effect of dummy fills. Experimental results show that the proposed method can decrease the effect of dummy fills on the Q-factor by 83% compared with the conventional dummy fill insertion.

[1]  C. Yue,et al.  On-chip Spiral Inductors With Patterned Ground Shields For Si-based RF IC's , 1997, Symposium 1997 on VLSI Circuits.

[2]  Koen Mouthaan,et al.  On-chip vertical tapered solenoid inductor with high self-resonance frequency , 2007 .

[3]  Keun-Ho Lee,et al.  Analyzing the effects of floating dummy-fills: from feature scale analysis to full-chip RC extraction , 2001, International Electron Devices Meeting. Technical Digest (Cat. No.01CH37224).

[4]  On-chip spiral inductors with patterned ground shields for Si-based RF ICs , 1998 .

[5]  R. Hoofman,et al.  The effect of copper design rules on inductor performance , 2003, ESSDERC '03. 33rd Conference on European Solid-State Device Research, 2003..

[6]  J.A. Yeh,et al.  Characterization of spiral inductors with patterned floating structures , 2004, IEEE Transactions on Microwave Theory and Techniques.

[7]  H. Onodera,et al.  Measurement of interconnect loss due to dummy fills , 2007, 2007 IEEE Workshop on Signal Propagation on Interconnects.

[8]  Bian Zhi-xin,et al.  Analyzing the Lithography Part of the International Technology Roadmap for Semiconductors (2005 Edition) , 2006 .

[9]  Yong-Zhong Xiong,et al.  Experimental Characterization of the Effect of Metal Dummy Fills on Spiral Inductors , 2007, 2007 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium.

[10]  H. Onodera,et al.  Analytical Estimation of Interconnect Loss Due to Dummy Fills , 2006, 2006 IEEE Electrical Performane of Electronic Packaging.

[11]  Peter R. Kinget,et al.  Voltage-controlled oscillator in the coil , 2005, Proceedings of the IEEE 2005 Custom Integrated Circuits Conference, 2005..

[12]  Hongrui Jiang,et al.  On-chip spiral inductors suspended over deep copper-lined cavities , 2000 .

[13]  Hyun-Kyu Yu,et al.  Effects of dummy patterns and substrate on spiral inductors for sub-micron RF ICs , 2002, 2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278).

[14]  Akira Tsuchiya,et al.  Dummy fill Insertion considering the effect on high-frequency characteristics of spiral inductors , 2008, 2008 IEEE MTT-S International Microwave Symposium Digest.

[15]  Atsushi Kurokawa,et al.  Dummy filling methods for reducing interconnect capacitance and number of fills , 2005, Sixth international symposium on quality electronic design (isqed'05).