A compact transport and charge model for GaN-based high electron mobility transistors for RF applications

Gallium Nitride (GaN)-based high electron mobility transistors (HEMTs) are rapidly emerging as front-runners in high-power mm-wave circuit applications. For circuit design with current devices and to allow sensible future performance projections from device engineering in such a rapidly evolving technology, compact device models are essential. In this thesis, a physics-based compact model is developed for short channel GaN HEMTs. The model is based on the concept of virtual source (VS) transport originally developed for scaled silicon field effect transistors. Self-consistent current and charge expressions in the model require very few parameters. The parameters have straightforward physical meanings and can be extracted through independant measurements. The model is implemented in Verilog-A and is compatible with state of the art circuit simulators. The new model is calibrated and validated with experimental DC I-V and S-parameter measurements of fabricated devices. Using the model, a projection of cut-off frequency (fT ) of GaN-based HEMTs with scaling is performed to highlight performance bottlenecks. Thesis Supervisor: Dimitri A. Antoniadis Title: Ray and Maria Stata Professor of Electrical Engineering

[1]  U. Mishra,et al.  The impact of surface states on the DC and RF characteristics of AlGaN/GaN HFETs , 2001 .

[2]  Debdeep Jena,et al.  Effect of Optical Phonon Scattering on the Performance of GaN Transistors , 2010, IEEE Electron Device Letters.

[3]  Xiang Gao,et al.  InAlN/GaN HEMTs With AlGaN Back Barriers , 2011, IEEE Electron Device Letters.

[4]  R. E. Thomas,et al.  Carrier mobilities in silicon empirically related to doping and field , 1967 .

[5]  J. J. Tietjen,et al.  THE PREPARATION AND PROPERTIES OF VAPOR‐DEPOSITED SINGLE‐CRYSTAL‐LINE GaN , 1969 .

[6]  G. T. Wright,et al.  Threshold modelling of MOSFETs for CAD of CMOS-VLSI , 1985 .

[7]  M. Shur,et al.  Monte Carlo simulation of electron transport in gallium nitride , 1993 .

[8]  H. Kondoh,et al.  An Accurate FET Modelling from Measured S-Parameters , 1986, 1986 IEEE MTT-S International Microwave Symposium Digest.

[9]  Jasprit Singh,et al.  Design of high electron mobility devices with composite nitride channels , 2003 .

[10]  Robert A. York,et al.  A scalable EE_HEMT based large signal model for multi-finger AlGaN/GaN HEMTs for linear and non-linear circuit design , 2010 .

[11]  S. Keller,et al.  Influence of the dynamic access resistance in the g/sub m/ and f/sub T/ linearity of AlGaN/GaN HEMTs , 2005, IEEE Transactions on Electron Devices.

[12]  A. Khakifirooz,et al.  A Simple Semiempirical Short-Channel MOSFET Current–Voltage Model Continuous Across All Regions of Operation and Employing Only Physical Parameters , 2009, IEEE Transactions on Electron Devices.

[13]  Y. Tsividis.  Operation and modeling of the MOS transistor , 1987 .

[14]  A. Schmitz,et al.  Deeply-scaled self-aligned-gate GaN DH-HEMTs with ultrahigh cutoff frequency , 2011, 2011 International Electron Devices Meeting.

[15]  K. Y. Tong,et al.  A thermal model for static current characteristics of AlGaN∕GaN high electron mobility transistors including self-heating effect , 2006 .

[16]  D. Antoniadis,et al.  Physics-based GaN HEMT transport and charge model: Experimental verification and performance projection , 2012, 2012 International Electron Devices Meeting.

[17]  Patrick Fay,et al.  245-GHz InAlN/GaN HEMTs With Oxygen Plasma Treatment , 2011, IEEE Electron Device Letters.

[18]  T. Mimura,et al.  A New Field-Effect Transistor with Selectively Doped GaAs/n-AlxGa1-xAs Heterojunctions , 1980 .

[19]  D. Antoniadis,et al.  Extraction of virtual-source injection velocity in sub-100 nm III–V HFETs , 2009, 2009 IEEE International Electron Devices Meeting (IEDM).

[20]  Walter Kruppa,et al.  Trapping effects and microwave power performance in AlGaN/GaN HEMTs , 2001 .

[21]  Isamu Akasaki,et al.  Nitride semiconductors—impact on the future world , 2002 .

[22]  Mark S. Lundstrom,et al.  Essential physics of carrier transport in nanoscale MOSFETs , 2000, 2000 International Conference on Simulation Semiconductor Processes and Devices (Cat. No.00TH8502).

[23]  R.W. Dutton,et al.  A charge-oriented model for MOS transistor capacitances , 1978, IEEE Journal of Solid-State Circuits.

[24]  L Dunleavy,et al.  Modeling GaN: Powerful but Challenging , 2010, IEEE Microwave Magazine.

[25]  U. Mishra,et al.  AlGaN/GaN HEMTs-an overview of device operation and applications , 2002, Proc. IEEE.

[26]  M. Asif Khan,et al.  High electron mobility transistor based on a GaN‐AlxGa1−xN heterojunction , 1993 .

[27]  W. Curtice,et al.  A Nonlinear GaAs FET Model for Use in the Design of Output Circuits for Power Amplifiers , 1985 .

[28]  Arvydas Matulionis,et al.  Ultrafast Removal of LO-Mode Heat From a GaN-Based Two-Dimensional Channel , 2010, Proceedings of the IEEE.

[29]  Jin-Wook Chung,et al.  Millimeter-wave GaN high electron mobility transistors and their integration with silicon electronics , 2011 .

[30]  Hideki Hasegawa,et al.  Mechanisms of current collapse and gate leakage currents in AlGaN/GaN heterostructure field effect transistors , 2003 .

[31]  G. Meneghesso,et al.  Current Collapse and High-Electric-Field Reliability of Unpassivated GaN/AlGaN/GaN HEMTs , 2006, IEEE Transactions on Electron Devices.

[32]  R. van Langevelde,et al.  Effect of gate-field dependent mobility degradation on distortion analysis in MOSFETs , 1997 .

[33]  H. Zirath,et al.  A new empirical nonlinear model for HEMT and MESFET devices , 1992 .

[34]  Lan Wei,et al.  Virtual-Source-Based Self-Consistent Current and Charge FET Models: From Ballistic to Drift-Diffusion Velocity-Saturation Operation , 2012, IEEE Transactions on Electron Devices.

[35]  Michael S. Shur,et al.  Induced strain mechanism of current collapse in AlGaN/GaN heterostructure field-effect transistors , 2001 .

[36]  MILTON FENG,et al.  Device technologies for RF front-end circuits in next-generation wireless communications , 2004, Proceedings of the IEEE.