Effect of Substrate Contact Shape and Placement on RF Characteristics of 45 nm Low Power CMOS Devices

The substrate resistance of 45 nm CMOS devices shows a strong dependence on the distance between the device edge and the substrate ring; as well as on the number of sides that the device is surrounded by the contact ring. We find that the unilateral gain is impacted by the substrate resistance (R[su...

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Bibliographic Details
Main Authors: Jagannathan, Basanth (Author), Wang, Jing (Author), Sweeney, Susan (Author), Li, Hongmei (Author), Gogineni, Usha (Contributor), del Alamo, Jesus A. (Contributor)
Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science (Contributor)
Format: Article
Language:English
Published: Institute of Electrical and Electronics Engineers, 2010-10-14T19:29:36Z.
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Summary:The substrate resistance of 45 nm CMOS devices shows a strong dependence on the distance between the device edge and the substrate ring; as well as on the number of sides that the device is surrounded by the contact ring. We find that the unilateral gain is impacted by the substrate resistance (R[subscript sx]) through the gate-body capacitance feedback path at low to medium frequencies (< 20 GHz). At mm wave frequencies, the unilateral gain is affected by the R[subscript sx] through the drain-body capacitance pole, and deviates from the ideal -20 dB/dec slope. The impact of substrate resistance on f[subscript T], maximum available gain, high frequency noise and power characteristics of the devices is minimal.