Conduction Cooling Limits for Power Semiconductor Nanostructures (NJTT)

Sponsors: 
DARPA NJTT Program (4 separate contracts), as well as separate contracts with Raytheon, Northrop Grumman, and BAE Systems

A variety of modern high-power electronic devices are based on high electron mobility transistors (HEMT) and generate enormous heat fluxes that can approach tens of kW/cm2. The overall power conversion capabilities are strongly limited by nanoscale heat transfer within and near active regions in the functional materials such as GaN and AlGaN. We are working with collaborators to develop novel composite substrates to dramatically reduce temperatures in these devices, including novel composites based on CVD diamond, which has the highest room temperature thermal conductivity. Stanford has a history of work on composite silicon-diamond substrates dating back 20 years, in particular focussing on the interface resistance at diamond boundaries.

For the resurgent interest in diamond composites for HEMT technology, we have developed a comprehensive optical and electrical measurement strategy to capture the thermal transport properties within the complex nanoscale multilayers in exploratory HEMT devices. Breakthrough measurement results include the anisotropic thermal conductivities in GaN functional layers, thermal resistances at diamond interfaces in novel HEMT composite substrates, as well as process-dependent properties of buffer layers. Measurement approaches include picosecond and nanosecond thermoreflectance, in which differing timescales are used to extract properties at varying depths within complex multilayers. We are also using narrow electrical heaters and thermometers, patterned using e-beam lithography down to widths as low as 50 nm, to extract the anisotropic conduction properties. Transmission electron microscopy yields details about interface and material quality, which serve as the basis for simulations of phonon transport. Simulations are also used to show the impact of the properties on HEMT device temperatures.

PROJECT PUBLICATIONS

Park, W., Sood, A., Park, J., Asheghi, M., Sinclair, R., and Goodson, K.E., "Enhanced Thermal Conduction through Nanostructured Interfaces," 2017, Nanoscale and Microscale Thermophysical Engineering, Nanoscale and Microscale Thermophysical Engineering, pp. 1-11.

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Cho, J., Francis, D., Altman, D.H., Asheghi, M., and Goodson, K.E., 2017, "Phonon Conduction in GaN-Diamond Composite Substrates," Journal of Applied Physics, Vol. 121, 055105.

 

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Sood, A., Cho, J., Hobart, K.D., Feygelson, T.I., Pate, B.B., Asheghi, M., Cahill, D.G., and Goodson, K.E., 2016, "Anisotropic and Inhomogeneous Thermal Conduction in Suspended Thin-Film Polycrystalline Diamond," Journal of Applied Physics, Vol. 119, 175103.

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Cho, J., and Goodson, K.E., 2015, "Thermal Transport: Cool Electronics," Nature Materials, Vol. 14, pp. 136-137.

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Cho, J.Sood, A., Hayee, F., Asheghi, M., Goodson, K.E., "Thermal Characterization of Nanocrystalline Diamond Films on Silicon", ASME International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems (InterPACK) 2015, July 6 - July 9, San Francisco, CA.

 

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Cho, J., Won, Y., Francis, D., Asheghi, M., and Goodson, K.E., "Thermal Interface Resistance Measurements for GaN-on-Diamond Composite Substrates," IEEE Compound Semiconductor Integrated Circuit Symposium (CSICS) 2014, Oct. 19-22, La Jolla, CA, USA.

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Tyhach, M., Altman, D., Bernstein, S., Korenstein, R., Cho, J., Goodson, K.E., Francis, D., Faili, F., Ejeckam, F., Kim, S., and Graham, S., "S2-T3: Next generation gallium nitride HEMTs enabled by diamond substrates," IEEE Lester Eastman Conference on High Performance Devices (LEC) 2014, Aug. 5-7, Ithaca, NY, USA.

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Cho, J., Li, Y., Hoke, W., Altman, D.A., Asheghi, M., and Goodson, K.E., 2014, "Phonon scattering in strained transition layers for GaN heteroepitaxy," Physical Review B, Vol. 89, 115301.

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Cho, J., Francis, D., Chao, P.C., Asheghi, M., and Goodson, K.E., 2015, "Cross-Plane Phonon Conduction in Polycrystalline Silicon Films," Journal of Heat Transfer, Vol. 137, 071303.

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Aly, M.M.S., Gao, M., Hills, G., Lee., C.-S., Pitner, G., Shulaker, M.M., Wu, T.F., Asheghi, M., Bokor, J., Franchetti., F., Goodson, K.E., Kozyrakis, C., Markov, I., Olukotin, K., Pileggi, L., Pop, E., Rabaey, J., Re, C., Wong, H.-S., Mitra, S., 2015, "Energy-Efficient Abundant-Data Computing:  The N3XT 1,000X," IEEE Computer, Vol. 48, pp. 24-33.

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Won, Y., Cho, J., Agonafer, D., Asheghi, M., Goodson, K.E., 2015, "Fundamental Cooling Limits for High Power Density GaN Electronics," IEEE Transactions on Components, Packaging and Manufacturing Technology, Vol. 5, pp. 737-744.

 

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Cho, J., Chu, K.K., Chao, P.C., McGray, C., Asheghi, M., and Goodson, K.E., "Thermal Conduction Normal to Thin Silicon Nitride Films on Diamond and GaN", IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITHERM) 2014, May 27 - 30, Orlando, FL, USA.

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Cho, J., Chao, P.C., Asheghi, M., and Goodson, K.E., "Phonon Conduction Normal to Polysilicon Films on Diamond," ASME 4th Micro/Nanoscale Heat & Mass Transfer (MNHMT) International Conference 2013, Dec. 11-14, Hong Kong, China.

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Won, Y.*, Cho, J.*, Agonafer, D., Asheghi, M., and Goodson, K.E., "Cooling Limits to GaN HEMT Technology," IEEE Compound Semiconductor Integrated Circuit Symposium (CSICS) 2013, Oct. 13-16, Monterey, CA, USA.

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Cho, J., Li, Z., Asheghi, M., and Goodson, K.E., "Phonon-Defect Scattering and the Thermal Resistance of the Transition Layers for GaN Heteroepitaxy", Materials Research Society (MRS) Spring Meeting, April 1-5, San Francisco, CA

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Cho, J., Li, Z., Asheghi, M., and Goodson, K. E., 2014, "Near-Junction Thermal Management: Thermal Conduction in Gallium Nitride Composite Substrates," Annual Review of Heat Transfer, Vol. 18, 2016.

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Bozorg-Grayeli, E., Sood, A., Asheghi, M., Gambin, V., Sandhu, R., Feygelson, T.I., Pate, B.B., Hobart, K., and Goodson, K.E., 2013, "Thermal Conduction Inhomogeneity of Nanocrystalline Diamond Films by Dual-Side Thermoreflectance," Applied Physics Letters, Vol. 102, 111907.

Erratum: http://scitation.aip.org/content/aip/journal/apl/108/17/10.1063/1.4948382

 

 

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Cho., J., Li, Z., Bozorg-Gayeli, E., Kodama, T., Francis, D., Ejeckam, F., Faili, F., Asheghi, M., and Goodson, K.E., 2013,"Improved Thermal Interfaces of GaN-Diamond Composute Substrates for HEMT Applications," IEEE Transactions on Components, Packaging, and Manufacturing Technology, Vol. 3, pp. 79-84.

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Cho, J., Li, Z., Bozorg-Grayeli, E., Kodama, T., Francis, D., Ejeckam, F., Faili, F., Asheghi, M., Goodson, K.E., “Thermal Characterization of GaN-on-Diamond Substrates for HEMT Applications,” IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITHERM) 2012, May 30 - June 1, San Dego, CA

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Cho, J., Li, Z., Bozorg-Grayeli, E., Kodama, T., Francis, D., Altman, D., Ejeckam, F., Faili, F., Asheghi, M., Goodson, K.E., “Thermal Characterization of Composite GaN Substrates for HEMT Applications,” Government Microcircuit Applications & Ctritical Technology (GomacTech) Conferfence 2012, March 18-20, Las Vegas, Nevada 

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Aminfar, A., Bozorg-Grayeli, E., Asheghi, M., and Goodson, K.E., "Analysis of HEMT Multilayered Structures Using a 2D Finite Volume Model", IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITHERM) 2012, May 30 - June 1, San Diego, CA

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Bozorg-Grayeli, E., Li, Z., Gambin, V., Asheghi, M., and Goodson, K.E., "Thermal Conductivity, Anisotropy, and Interface Resistances of Diamond on Poly-AlN", IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITHERM) 2012, May i30 - June 1, San Dego, CA

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Cho, J., Bozorg-Grayeli, E., Altman, D.H., Asheghi, M., and Goodson, K.E., 2012, "Low Thermal Resistances at GaN-SiC Interfaces for HEMT Technology," IEEE Electron Device Letters, Vol. 33, pp. 378-380.

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Touzelbaev, M.N., and Goodson K.E., 1997, "Impact of Nucleation Density on Thermal Resistance Near Diamond-Substrate Boundaries," AIAA Journal of Thermophysics and Heat Transfer, Vol. 11, pp. 506-512.

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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.

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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.

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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.

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Goodson, K.E., 1996, "Thermal Conduction in Nonhomogeneous CVD Diamond Layers in Electronic Microstructures," ASME Journal of Heat Transfer, Vol. 118, pp. 279-286.

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Goodson, K.E., Kading, O.W., Rosler, M. and Zachai, R., 1995, "Thermal Conduction normal to Diamond-Silicon Boundaries," Applied Physics Letters, Vol. 66, pp. 3134-3136.

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Goodson, K.E., Kading, O.W., Rosler, M. and Zachai, R., 1995, "Experimental Investigation of Thermal Conduction normal to Diamond-Silicon Boundaries," Journal of Applied Physics, Vol. 77, pp. 1385-1392.

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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.

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Goodson, K.E., and Flik, M.I., 1994, "Solid-Layer Thermal-Conductivity Measurement Techniques," Applied Mechanics Reviews, Vol. 47, pp. 101-112.

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