Research Papers

Thermal Analysis of AlGaN/GaN HEMTs Using Angular Fourier-Series Expansion

[+] Author and Article Information
Dubravko I. Babić

Faculty of Electrical Engineering
and Computing,
University of Zagreb,
Zagreb, Croatia;
Group4 Labs, Inc.,
3485 Edison Way, Menlo Park, CA 94035
e-mail: dubravko.babic@group4labs.com

Contributed by the Heat Transfer Division of ASME for publication in the Journal of Heat Transfer. Manuscript received December 19, 2011; final manuscript received November 6, 2012; published online September 23, 2013. Assoc. Editor: Sujoy Kumar Saha.

J. Heat Transfer 135(11), 111001 (Sep 23, 2013) (9 pages) Paper No: HT-11-1580; doi: 10.1115/1.4024594 History: Received December 19, 2011; Revised November 06, 2012

Thermal analysis of planar and near-square semiconductor device chips employing angular Fourier-series (AFS) expansion is presented for the first time. The determination of the device peak temperature using AFS requires only a single two-dimensional computation, while full three-dimensional temperature distribution can be obtained, if desired, by successively adding higher-order Fourier terms, each of which requires a separate 2D computation. The AFS method is used to compare the heat spreading characteristics of AlGaN/GaN high-electron-mobility transistors (HEMTs) fabricated on silicon, silicon carbide, and synthetic diamond. We show that AlGaN/GaN HEMTs built using GaN/diamond technology can offer better than half the thermal resistance of GaN/SiC HEMTs under worst-case cooling conditions. Furthermore, we show that, if left unmanaged, an inherent and non-negligible thermal boundary resistance due to the integration of semiconductor epilayers with non-native substrates will dampen the benefits of highly conductive substrates such as SiC and diamond.

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Quay, R., 2008, Gallium Nitride Electronics, Springer-Verlag, New York.
Liu, W., and Balandin, A. A., 2005, “Thermal Conduction in AlxGa1-xN Alloys and Thin Films,” J. Appl. Phys., 97, p. 073710. [CrossRef]
Sarua, A., Ji, H., Hilton, K. P., Wallis, D. J., Uren, M. J., Martin, T., and Kuball, M., 2007, “Thermal Boundary Resistance Between GaN and Substrate in AlGaN/GaN Electronic Devices,” IEEE Trans. Electron. Devices, 54(12), pp. 3152–3157. [CrossRef]
Francis, D., Faili, F., Babić, D., Ejeckam, F., Nurmiko, A., Maris, H., 2010, “Formation and Characterization of 4-inch GaN-on-Diamond Substrates,” Diamond Relat. Mater., 19, pp. 229–233. [CrossRef]
Chabak, K. D., Gillespie, J. K., Miller, V., Crespo, A., Roussos, J., Trejo, M., Walker, D. E., Via, G. D., Jessen, G. H., Wasserbauer, J., Faili, F., Babić, D.I., Francis, D., and Ejeckam, F., 2010, “Full-Wafer Characterization of AlGaN/GaN HEMTs on Free-Standing CVD Diamond Substrates,” IEEE Electron Device Lett., 31(2), pp. 99–101. [CrossRef]
Kohn, E., Dipalo, M., Alomari, M., Mdjduob, F., Carlin, J.-F., Grandjean, N., and Delage, S., 2008, “A Concept for Diamond Overlayers on Nitride Heterostructures,” Development Research Conference, pp. 292–296.
Touzelbaev, M. N., and Goodson, K. E., 1998, “Application of Micron-Scale Passive Diamond Layers for the Integrated Circuits and Microelectromechanical Systems Industries,” Diamond Relat. Mater., 7, pp. 1–14. [CrossRef]
Ellison, G. N., 2003, “Maximum Thermal Spreading Resistance for Rectangular Sources and Plates With Nonunity Aspect Ratios,” IEEE Trans. Compon. Packag. Technol., 26(2), pp. 439–454. [CrossRef]
Zou, Y. S., Yang, Y., Chong, Y. M., Ye, Q., He, B., Yaho, Z. Q., Zhang, W. J., Lee, S. T., Cai, Y., and Chu, H. S., 2008, “Chemical Vapor Deposition of Diamond Films on Patterned GaN Substrates via a Thin Silicon Nitride Protective Layer,” Cryst. Growth Des., 8(5), pp. 1770–1773. [CrossRef]
May, P. W., Tsai, H. Y., Wang, W. N., and Smith, J. A., 2006, “Deposition of CVD Diamond on GaN,” Diamond Relat. Mater., 15 pp. 526–530. [CrossRef]
Oba, M., and Sugino, T., 2001, “Oriented Growth of Diamond on (0001) Surface of Hexagonal GaN,” Diamond Relat. Mater., 10, pp. 1343–1346. [CrossRef]
Seelmann-Eggbert, M., Meisen, P., Schaudel, F., Koidl, P., Vescan, A., and Leier, H., 2001, “Heat-Spreading Diamond Films for GaN-Based High-Power Transistors Devices,” Diamond Relat. Mater., 10, pp. 744–749. [CrossRef]
Piner, E. L., Zimmer, J. W., Roberts, J. C., Chandler, G., and Sadler, R. A., 2009, “Epi-Inverted N-Face GaN/Diamond for AlGaN/GaN/AlGaN FETs,” 2009 WOCSDICE Extended Abstracts, Session Mon4, p. 18.
Hageman, P. R., Schermer, J. J., and Larsen, P. K., 2009, “GaN Growth on Single-Crystal Diamond Substrates by Metalorganic Chemical Vapor Deposition and Hydride Vapor Deposition,” Thin Solid Films, 443, pp. 9–13. [CrossRef]
Alomari, M., Dussaigne, A., Martin, D., Grandjean, N., Gaquiere, C., and Kohn, E., 2010, “AlGaN/GaN HEMT on (111) Single-Crystalline Diamond,” Electronics Lett., 46(4), pp. 299–301. [CrossRef]
Diduck, Q., Felbinger, J., Eastman, L. F., Francis, D., Wasserbauer, J., Faili, F., Babić, D. I., and Ejeckam, F., 2009, “Frequency Performance Enhancement of AlGaN/GaN HEMTs on Diamond,” Electron. Lett.45, pp. 758–759. [CrossRef]
Babić, D. I., Diduck, Q., Yenigalla, P., Schreiber, A., Francis, D., Faili, F., Ejeckam, F., Felbinger, J. G., and Eastman, L. F., 2010, “GaN-on-Diamond Field-Effect Transistors: From Wafers to Amplifier Modules,” Proceedings of the Symposium on Microelectronics, Electronics, and Electronic Technologies (MEET), MIPRO, Opatija, Croatia, May 20–24.
Lee, S., Song, S., Au, V., and Moran, K. P., 1995, “Constriction/Spreading Resistance Model for Electronics Packaging,” ASME/JSME Thermal Engineering Conference, Vol. 4.
Cappelluti, F., Furno, M., Angelini, A., Bonani, F., Pirola, M., and Ghione, G., 2007, “On the Substrate Thermal Optimization in SiC-Based Backside-Mounted High Power GaN FETs,” IEEE Trans. Electron Devices, 54(7), pp. 1744–1752. [CrossRef]
Kuball, M., Killat, N., Manoi, A., and Pomeroy, J. W., 2010, “Benchmarking of Thermal Boundary Resistance of GaN-SiC Interfaces for AlGaN/GaN HEMTs: US, European and Japanese Suppliers,” CS MANTECH Conference Proceedings of May 17–20, Portland, OR.
Touzelbaev, M. N., and Goodson, K. E., 2007, “Impact of Nucleation Density on Thermal Resistance Near Diamond-Substrate Boundaries,” J. Thermophys. Heat Transfer, 11(4), pp. 506–511. [CrossRef]
Graebner, J. E., Jin, S., Kammlott, G. W., Wong, Y.-H., Herb, J. A., and Gardinier, C. F., 1993, “Thermal Conductivity and the Microstructure of the State-of-the-Art Chemical-Vapor-Deposited (CVD) Diamond,” Diamond Relat. Mater., 2, pp. 1059–1063. [CrossRef]
Philip, J., Hess, P., Feygelson, T., Butler, J. E., Chattopadhyay, S., Chen, K. H., and Chen, L. C., 2003, “Elastic, Mechanical, and Thermal Properties of Nanocrystalline Diamond Films,” J. Appl. Phys., 93(4), pp. 2164–2171. [CrossRef]
Darwish, A. M., Bayba, A. J., and Hung, H. A., 2004, “Thermal Resistance Calculation of AlGaN-GaN Devices,” IEEE Trans. Microwave Theory Tech., 52(11), pp. 2611–2620. [CrossRef]
Anholt, A., 1995, Electrical and Thermal Characterization of MESFETs, HEMTs, and HBTs, Artech House, Boston, MA.
Aaen, P. H., Plá, J. A., and Wood, J., 2007, Modeling and Characterization of RF and Microwave Power FETs, Cambridge University Press, Cambridge, UK.
Beck, J. V., Osman, A. M., and Lu, G., 1993, “Maximum Temperatures in Diamond Heat Spreaders Using the Surface Element Method,” J. Heat Transfer, 115, pp. 15–57. [CrossRef]
Negus, K. J., Yovanovich, M. M., and Beck, J. V., 1989, “On the Nondimensionalisation of Constricton Resistance for Semi-Infinite Heat Flux Tubes,” J. Heat Transfer, 111, pp. 804–807. [CrossRef]
Fushinobu, K., Majumdar, A., and Hijikata, K., 1995, “Heat Generation and Transport in Submicron Semiconductor Devices,” J. Heat Transfer, 117, pp. 25–31. [CrossRef]
Őzisik, M. N., 1985, Heat Transfer: A Basic Approach, McGraw-Hill, New York.
Clark, K., Ulrich, D. R., Gordon, D. M., and Leftwich, M., 1998, “Finite Element Thermal Model for High Power Transients in Microelectronics With CVD Diamond Heat Spreaders,” Electronic Components and Technology Conference, p. 1455.
Hui, P., and Tan, H. S., 1996, “Three-Dimensional Analysis of a Thermal Dissipation System With a Rectangular Heat Spreader on a Semi-Infinite Copper Heat Sink,” Jpn. J. Appl. Phys., Part 1, 35(9A), pp. 4852–4861. [CrossRef]
Singhal, S., Brown, J. D., Borges, R., Piner, E., Nagy, W., and Vescan, A., 2002, “Gallium Nitride on Silicon HEMTs for Wireless Infrastructure Applications, Thermal Design and Performance,” European Microwave Week, Milan, Italy.
Hui, P., and Tan, H. S., 1995, “A Rigorous Series Solution for a Thermal Dissipation System With a Diamond Heat Spreader on an Infinite Slab Heat Sink,” Jpn. J. Appl. Phys., Part 1, 34(9A), pp. 5056–5064. [CrossRef]
Rogacs, A., and Rhee, J., 2007, “Performance-Cost Optimization of a Diamond Heat Spreader,” IEEE Advanced Packaging Materials Symposium, p. 65.


Grahic Jump Location
Fig. 1

Epilayer designs of the HEMTs modeled in this work. The bold line indicates the location of the heat source (not the shape). Figure is not to scale; the chip width of practical transistors is many times larger than the chip thickness.

Grahic Jump Location
Fig. 2

Schematic of an electronic device chip with heat dissipation (the left dashed side indicates the symmetry). The temperature at the hottest spot in the structure is denoted with TP, the bottom center and edge of the chip TC and the bottom edge of the chip TB, respectively. The convection cooling below the chip is specified with the heat transfer coefficient h.

Grahic Jump Location
Fig. 3

Grid-point numbering: temperature is given at the grid points—the intersections between grid lines (i, j), heat fluxes are given at halfway distances between grid points, and the power generation and thermal conductivity is specified in the areas enclosed by adjacent grid lines—grid “elements” (i, j).

Grahic Jump Location
Fig. 4

Types of intersection between a circle and a square and the associated parameters

Grahic Jump Location
Fig. 5

Temperature and thermal conductivity profile at the origin of the coordinate system for device C

Grahic Jump Location
Fig. 6

Calculation times for a single-gate HEMT performed with AFS and conventional TDF thermal analysis (device A-II)

Grahic Jump Location
Fig. 7

Normalized thermal conductance for epi designs A, B, and C with heat source shape III

Grahic Jump Location
Fig. 8

Thermal resistance of structures A, B, and C′ as function of heat transfer coefficient (left axis). The solid symbols show TPTB, while the empty symbols show TC − TB. Right axis show the ratio of thermal resistance of GaN/SiC and GaN/Si devices divided by the thermal resistance of GaN/Diamond device.

Grahic Jump Location
Fig. 9

Thermal resistance under isoflux cooling versus diamond thermal conductivity for heat source III




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