Department of Mechanical Engineering

Stanford University

Principal Investigator

Kenneth E. Goodson

Sponsors:

SRC, ONR, NSF, Intel, AMD As the silicon transistor is scaled to deep submicrometer gate lengths, the microprocessor thermal management challenge has been extended to nanoscale thermal conduction and coupled electron-phonon transport within and near the active regions of devices. The electron temperatures in modern silicon devices can exceed several thousand Kelvin, which results in severe nonequilibrium between generated phonons and those responsible for conduction cooling of devices. These problems are amplified in novel transistor geometries (including silicon-on-insulator, FINFET, and related nanopillar devices) which impair heat conduction between active regions and the substrate.

Stanford has been at the forefront of electrothermal transport modeling and experiments for silicon nanotransistors for nearly two decades. Early work focused on thermal property measurements for silicon devices, including SOI silicon nanolayer and oxide layer conductivities. A variety of device thermometry techniques were developed, including gate electrical-resistance techniques (for DC temperature rise) and laser-reflectance thermometry (for 10 ns temporal resolution). More recently, our work has focused on the sub-continuum and nonequilibrium electron and phonon transport within active regions. This included solutions to the phonon Boltzmann transport equation both in SOI transistors and in traditional bulk devices, followed by coupled Monte Carlo/BTE simulations of both the electron and phonon systems in parallel. The goals of this research have been predictions of the impact on channel mobility, interconnect MTF, and device leakage currents.

**Panzer, M.A.,** Shandalov, M.,** Rowlette, J.A.,** Oshima, Y., Chen, Y.W., McIntyre, P.C., and Goodson, K.E., 2009, "Thermal Properties of Ultrathin Hafnium Oxide Gate Dielectric Films," *IEEE Electron Device Letters*, Vol. 30, pp. 1269-1271.

**Rowlette, J.A.**, and Goodson, K.E., 2008, "Fully-Coupled, Nonequilibrium, Electron-Phonon Transport in Nanometer-Scale Silicon FETs," *IEEE Transactions on Electronic Devices*, Vol. 55, pp. 220-232.

**Pop, E., Sinha, S.**, and Goodson, K.E., 2006, "Heat Generation and Transport in Nanometer Scale Transistors," *Proceedings of the IEEE*, Vol. 94, pp. 1587-1601.

**Sinha, S., Pop, E**., Dutton R.W., and Goodson, K.E., 2006, "Non-Equilibrium Phonon Distributions in Sub-100 nm Silicon Transistors," *ASME Journal of Heat Transfer*, Vol. 128, pp. 638-647.

**Sinha, S**., and Goodson, K.E., 2006, "Thermal Conduction in Sub-100nm Transistors," *Microelectronics Journal*, Vol. 37, pp. 1148-1157.

**Pop, E.**, and Goodson, K.E., 2006, "Thermal Phenomena in Nanoscale Transistors," *Journal of Electronic Packaging*, Vol. 128, pp. 102-108.

**Sinha S**., and Goodson, K.E., 2005, "Review: Multiscale Thermal Modeling in Nanoelectronics," *International Journal for Multiscale Computational Engineering*, Vol. 3, pp. 107-133.

**Sinha, S**., Shelling, P.K., Phillpot, S.R., Goodson, K.E., 2005, "Scattering of g-Process Longitudinal Phonons at Hotspots in Silicon," *Journal of Applied Physic*s, Vol. 97, no.2, pp. 023702-1-023702-9.

**Pop, E.**, Dutton, R.W., and Goodson, K.E., 2005, "Monte Carlo simulation of Joule Heating in Bulk and Strained Silicon," *Applied Physics Letters*, Vol. 86, pp. 082101-082103.

**Pop, E.**, Dutton, R.W., and Goodson, K.E., 2004, "Analytic Band Monte Carlo Model for Electron Transport Modeling in Si Including Acoustic and Optical Phonon Dispersion," *Journal of Applied Physics*, Vol. 96, pp. 4998-5005.

**Asheghi, M.**, **Kurabayashi, K.**, Kasnavi, K., and Goodson, K.E., 2002, "Thermal Conduction in Doped Single-Crystal Silicon Films," *Journal of Applied Physics*, Vol. 91, pp. 5079-5088.

**Sverdrup, P.G., Sinha, S., Uma, S., Asheghi, M.**, and Goodson, K.E., 2001, "Measurement of Ballistic Phonon Conduction Near Hotspots in Silicon," *Applied Physics Letters*, Vol. 78, pp. 3331-3333.

**Sverdrup, P.G., Ju, Y.S.,**and Goodson, K.E., 2001, "Sub-Continuum Simulations of Heat Conduction in Silicon-on-Insulator Transistors," *ASME Journal of Heat Transfer*, Vol. 123, pp. 30-37.

**Ju, Y.S.**, and Goodson, K.E., 1999, "Phonon Scattering in Silicon Films of Thickness Below 100 nm," *Applied Physics Letters*, Vol. 74, pp. 3005-3007.

**Asheghi, M., Touzelbaev, M.N.,** Goodson, K.E., Leung, Y.K., and Wong, S.S., 1998, "Temperature-Dependent Thermal Conductivity of Single-Crystal Silicon Layers in SOI Substrates," *ASME Journal of Heat Transfer*, Vol. 120, pp. 31-36.

**Ju, Y.S.,** and Goodson, K.E., 1998, "Short-Time-Scale Thermal Mapping of Microdevices using a Scanning Thermoreflectance Technique," *ASME Journal of Heat Transfer*, Vol. 120, pp. 306-313.

**Asheghi, M.**, Leung, Y.K., Wong, S.S., and Goodson, K.E., 1997, "Phonon-Boundary Scattering in Thin Silicon Layers," *Applied Physics Letters*, Vol. 71, pp. 1798-1800.

**Ju, Y.S., Kading, O.W.,** Leung, Y.K., Wong, S.S., and Goodson, K. E., 1997, "Short-Timescale Thermal Mapping of Semiconductor Devices," *IEEE Electron Device Letters*, Vol. 18, pp. 169-171.

Leung, Y.-K., Paul, A.K., Goodson, K.E., Plummer, J.D., and Wong, S.S., 1997, "Heating Mechanisms of LDMOS and LIGBT in Ultrathin SOI," *IEEE Electron Device Letters*, Vol. 18, pp. 414-416.

**Ju, Y.S.**, and Goodson, K.E., 1997, "Size Effect on the Thermal Conductivity of Silicon-on-Insulator Devices under Electrostatic Discharge (ESD) Conditions," *Japanese Journal of Applied Physics*, Part 2, Vol. 36, pp. L798-L800.

Goodson, K.E., Flik, M.I., Su, L.T., and Antoniadis, D.A., 1995, "Prediction and Measurement of Temperature Fields in Silicon-on-Insulator Electronic Circuits," *ASME Journal of Heat Transfer*, Vol. 117, pp. 574-581.

**Kading, O.W.**, Skurk, H., and Goodson, K.E., 1994, "Thermal Conduction in Metallized Silicon-Dioxide Layers on Silicon," *Applied Physics Letters*, Vol. 65, pp. 1629-1631.

Su, L.T., Chung, J.E., Antoniadis, D.A., Goodson, K.E., and Flik, M.I., 1994, "Measurement and Modeling of Self-Heating in SOI nMOSFETS," *IEEE Transactions on Electron Devices*, Vol. 41, pp. 69-75.

Goodson, K.E., Flik, M.I., Su, L.T., and Antoniadis, D.A., 1994, "Prediction and Measurement of the Thermal Conductivity of Amorphous Dielectric Layers," *ASME Journal of Heat Transfer*, Vol. 116, pp. 317-324.

Goodson, K.E., Flik, M.I., Su, L.T., and Antoniadis, D.A., 1993, "Annealing-Temperature Dependence of the Thermal Conductivity of LPCVD Silicon-Dioxide Layers," *IEEE Electron Device Letters*, Vol. 14, pp. 490-492.

Goodson, K.E., and Flik, M.I., 1992, "Effect of Microscale Thermal Conduction on the Packing Limit of Silicon-on-Insulator Electronic Devices," *IEEE Transactions on Components, Hybrids, and Manufacturing Technology*, Vol. 15, pp. 715-722.

Flik, M.I., Choi, B.I., and Goodson, K.E., 1992, "Heat Transfer Regimes in Microstructures," *ASME Journal of Heat Transfer*, Vol. 114, pp. 666-674.