Quasi-Physical Zone Division (QPZD) Model for Wide- bandgap Semiconductor Technology

1. MMT 微波毫米波集成电路与系统实验室 Microwave and Millimeter-wave Technology(MMT) Lab Quasi-Physical Zone Division (QPZD) Model for Wide-bandgap Semiconductor Technology YuehangXuEmail:yuehangxu@uestc.edu.cn

2. Outline Background Theory of QPZD model QPZD Diamond FET model Summary

3. Ⅰ. Background Trends of RF transistors

4. Ⅰ. Background

5. Ⅰ. Background Compact model coalition(CMC) UESTC model since 2005 Empirical model (Angelov) Physical compact model

6. Ⅰ. Background Physical compact models Pao-SahI-VCurrent equation IEEE Trans. Electron Devices, 52(8),1868-1873, 2005. • Surface potential model (i.e. ASM-HEMT) • Charge based model ( i.e. MVSG) • Advantages • More intuitive in physics; • Less fitting parameters; • Naturally scalable; Is there any model with less fitting parameters, high convergence for microwave application? • Problems • Increasing fitting parameters when considering self-heating, ambient temperature, and trapping effects; • Easily not convergence in microwave high power amplifiers (HPAs) ;

7. Outline Background Theory of QPZD model QPZD Diamond FET model Summary

8. Theory of QPZD model Zone Division Saturation operation Triode operation Intrinsic FET Zone(IFZ) Space-charge Limited Zone(SLZ) Charge Deficit Zone(CDZ)

9. Theory of QPZD model Drain current model D. Hou, G. L. Bilbro, and R. J. Trew, IEEE TED , 2013. • Zhang wen, YuehangXu* , et al.，IEEE T-MTT, 2017,65(12):5113-5122

10. Theory of QPZD model Capacitance models Gate channel capacitance Cgc in ON state Inner fringing capacitance Cif in OFF state Bias-dependent The depletion regions • YonghaoJia , YuehangXu*,etc. IEEE T-ED, 2019,66(1):357-362

11. Theory of QPZD model Analytical capacitance equations Ward–Dutton charge partition (IEEE JSSCC,1980)

12. Theory of QPZD model Includes self-heating, ambient temperature, trapping effects

13. Theory of QPZD model Does it work for GaN HEMTs and MMICs? （a）2×125μm （b）6×100μm （c）8×125μm 0.25um GaN HEMT, 4*125um, Vgs=-3V, Vds=25V

14. Theory of QPZD model Does it work for GaN HEMTs and MMICs? X-band MMIC

15. Theory of QPZD model Is it physical enough for statistical model ? Statistical property of physical parameters: d, vmax, nsmax, µsat DC-IV Measurement for batches of devices Statistical Model Automatic Parameter Extraction Parameter Data Set ns µ a0, a1, b0, b1, b2 d vmax nsmax, α1, α2, α3, βn Factor Analysis Statistical Model • Zhang Wen , Shuman Mao, YuehangXu*,etc. IEEE IMS, 2019

16. Theory of QPZD model Factor Analysis (FA) Factor Calculation Load Matrix Correlation Coefficient Common Factor Standardization

17. Theory of QPZD model vmax d µsat nsmax

18. Theory of QPZD model Statistical Property of the Physical Parameters Simulation Measured

19. Theory of QPZD model Power Sweep Characteristics

20. Theory of QPZD model Sensitive Analysis in Power Sweep vmax ns

21. Theory of QPZD model Sensitive Analysis in Impedance Chart

22. Outline Background Theory of QPZD model QPZD Diamond FET model Summary

23. Diamond FET model Michale W. Geis, Phys. Status Solidi A.2018

24. Diamond FET model Power Electronics Application RF Electronics Application • High-Temperature • High-Power • High-Frequency Application • Lower Energy Consumption • Higher Output Power

25. Diamond FET model Univ of Bristol: Martin Kuball Univ of Glasgow: David Moran Univ of Ulm: E.Kohn Institute Neel:Pham Waseda University Hiroshi Kawarada Saga University Makoto Kasu Univ of Rome Tor Vergata: Pasciuto World-scale Diamond Device Research Distribution

26. Diamond FET model Developments of TCAD Simulation Models for C-H Diamond FETs 2001 • 0.2 nm p-type doping in diamond surface • H atoms of the C-H bonds act as surface acceptors 2017 • Negative fixed charge sheet induces a 2DHG channel • transfer doping mechanism due to C-H dipoles and surface adsorbates is not clear 2017 • Negative charge sheet (source to drain) induces a 2DHG channel, and positive charge sheet (under gate) calibrates the model • Not explain the physical meaning of the positive charge sheet and the role of surface adsorbate layer in the transfer doping

27. Diamond FET model C-H Diamond FET Operation Mechanism and TCAD Model C-H dipole effect induced transfer doping mechanism I-V characteristics Transfer characteristics • Drift-Diffusion transport equation • Wachutka’s thermodynamically rigorous model • Shockley-Read-Hall (SRH) Recombination Model Yu Fu, RuiminXu, …, YuehangXu* IEEE EDL, 2018

28. Diamond FET model Zone division for diamond FET TCAD simulation

29. Diamond FET model Linear-mode I-V Model Parameter Extraction and Modeling Basic assumption

30. Diamond FET model COMSOL VS 38.73 C/W 33.81 C/W C-H Diamond FET

31. Diamond FET model I-V Model Verification Saturated-mode I-V model LG= 0.5 m, WG = 2* 500 m Modeling Flowchart

32. Diamond FET model Small signal S-Parameter Extraction and Verification

33. Diamond FET model Large-signal Modeling and Verification 1 GHz Power Sweep Electrothermal large signal model topology Yu Fu, RuiminXu, …, YuehangXu*,IEEE Access, 2019 2 GHz Power Sweep

34. Outline Background Theory of QPZD model QPZD Diamond FET model Summary

35. Summary • QPZD model is validated by GaN HEMT transistors and further validated by a X-band GaNHigh power amplifier • QPZD statistical model is used for MMIC yield analysis • QPZD model is used for microwave diamond FETs

36. Acknowledgement