Released Resonant Body Transistor with MIT Virtual Source (RBT-MVS) Model 1.0.0

By Bichoy W. Bahr1, Dana Weinstein1, Luca Daniel1

Massachusetts Institute of Technology (MIT)

An RBT is a micro-electromechanical (MEM) resonator with a transistor (FET) incorporated into the resonator structure to sense the mechanical vibrations. This is a fully-featured spice-compatible compact model for fast analysis of RBTs.

Listed in Compact Models | publication by group NEEDS: New Era Electronic Devices and Systems

Additional materials available

Version 1.0.0 - published on 30 Aug 2015 doi:10.4231/D3VH5CK04 - cite this

Licensed under NEEDS Modified CMC License according to these terms



See more compact models using the MIT Virtual Source (MVS) Model

An RBT is a micro-electromechanical (MEM) resonator with a transistor (FET) incorporated into the resonator structure to sense the mechanical vibrations.
The electrostatic drive of RBTs using internal dielectric transduction, along with the FET sensing, enable these devices to easily scale to multi-GHz frequencies.
Together with the potential for monolithic CMOS integration, they represent a potential candidate for uncountable timing and RF applications that continuously drive the technology towards miniaturization, and aggressive reduction of power consumption.
This compact model is developed with the aim to capture the diverse and highly coupled physics intrinsic to the original RBT.
The model is aimed at presenting a deep insight into the physics of the RBT while emphasizing the effect of the different parameters on the device performance.
It is also intended to grant circuit designers and system architects the ability to quickly assess the performance of prospective RBTs, while minimizing the need for computationally intensive coupled-multiphysics finite element method (FEM) simulations.
The model relies on on a modified version of the MIT Virtual Source (MVS) model to implement both the electrostatic driving (as a MOSCAP) and the piezoresistive FET sensing.

Model Release Components ( Show bundle contents ) Bundle

Key References

  1. [1]  D. Weinstein and S. A. Bhave, “The Resonant Body Transistor,” Nano Letters, vol. 10, no. 4, pp. 1234–1237, 2010.

  2. [2]  B. Bahr, R. Marathe, and D. Weinstein, “Theory and design of phononic crystals for unreleased cmos-mems resonant body transistors,” Microelectromechanical Systems, Journal of, vol. PP, no. 99, pp. 1–1, 2015.

  3. [3]  D. Weinstein and S. Bhave, “Internal dielectric transduction in bulk-mode resonators,” Microelectromechanical Systems, Journal of, vol. 18, no. 6, pp. 1401– 1408, Dec 2009.

  4. [4]  B. Auld, Acoustic Fields and Waves in Solids: vol. 1, ser. Acoustic Fields and Waves in Solids. Krieger Publishing Company, 1990.

  5. [5]  R. Tabrizian, M. Rais-Zadeh, and F. Ayazi, “Effect of phonon interactions on limiting the f.q product of micromechanical resonators,” in Solid-State Sensors, Actuators and Microsystems Conference, 2009. TRANSDUCERS 2009. In- ternational, June 2009, pp. 2131–2134.

  6. [6]  T. Gabrielson, “Mechanical-thermal noise in micromachined acoustic and vibration sensors,” Electron Devices, IEEE Transactions on, vol. 40, no. 5, pp. 903– 909, May 1993.

  7. [7]  S. Senturia, Microsystem Design. Springer US, 2005.

  8. [8]  BSIM models. [Online]. Available:

  9. [9]  S. Rakheja and D. Antoniadis. (2015, Aug) MVS nanotransistor model (silicon). [Online]. Available:

  10. [10]  R.Marathe,B.Bahr,W.Wang,Z.Mahmood,L.Daniel,andD.Weinstein,“Resonant Body Transistors in IBM’s 32 nm SOI CMOS Technology,” J. Microelectromech. Syst., no. 99, pp. 1–1, 2013.

  11. [11]  Y. Kanda and Y. Kanda, “A graphical representation of the piezoresistance coefficients in silicon,” Electron Devices, IEEE Transactions on, vol. 29, no. 1, pp. 64–70, 1982. 

           [12] H. Baltes, O. Brand, G. Fedder, C. Hierold, J. Korvink, and O. Tabata, CMOS- MEMS: Advanced Micro and Nanosystems, ser. Advanced Micro and Nanosystems. Wiley, 2008.

  1. [13]  D. Hodgesand H. Shichman,“Large-signal insulated-gate field-effect transistor model for computer circuit simulation,” in Solid-State Circuits Conference. Digest of Technical Papers. 1968 IEEE International, vol. XI, Feb 1968, pp. 70– 71.

  2. [14]  Cadence design systems, inc. [Online]. Available: en/default.aspx 

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RBT-MVS version 1.0.0

Model Files:

  • Top level module, the main model interface
  •  rbtConst.vams: Model constants
  • Resonant body module
  • Modified MVS model to model the sensing FET
  • Modified MVS model to model MOS Cap driving
  • Electrostatic transducer module [not used by default]
  • Parasitics modeling module
  • Thermal model module
  • Definition for the strain Verilog-A nature
  •  memsquantities.scs: More reasonable tolerances for the MEMS quantities

Top Module:
The file includes the definition for the model top module.
This module should be used in circuit netlists (using an "ahdl_include" 
    statement for Spectre) as it represent the complete model.
The file memsquantities.scs should also be included in spectre netlists.

Testing the model:
A sample netlist is provided in the directory ../testing along with a GNU make file.
To run the model, it is sufficient to have the user's $PATH environment variable properly 
pointing to Cadence Spectre and issuing the command:

    make sim

If Cadence Custom IC design tools is also included in the user's $PATH environment
variable, the following command can be used to view the simulation results:

    make view

This command starts Cadence Visualization tool.
An Ocean script (plot.ocn) is also provided for plotting relevant results. To use it,
in Cadence Visulation tool issue the command:

    load "plot.ocn"