[papers] Compact/SPICE Modeling

[1] Wang, Jie; Chen, Zhanfei; You, Shuzhen; Bakeroot, Benoit; Liu, Jun; Decoutere, Stefaan; "Surface-Potential-Based Compact Modeling of p-GaN Gate HEMTs" Micromachines (2021) 12, no. 2: 199; https://doi.org/10.3390/mi12020199

Abstract: We propose a surface potential (SP)-based compact model of p-GaN gate high electron mobility transistors (HEMTs) which solves the Poisson equation. The model includes all possible charges in the GaN channel layer, including the unintended Mg doping density caused by out-diffusion. The SP equation and its analytical approximate solution provide a high degree of accuracy for the SP calculation, from which the closed-form I–V equations are derived. The proposed model uses physical parameters only and is implemented in Verilog-A code.

Fig: The equivalent circuit of the capacitance of field plates (FPs) of a p-GaN gate HEMT.

[2] Chen, H. and He, L.,  The spatial and energy distribution of oxide trap responsible for 1/f noise in 4H-SiC MOSFETs. Journal of Physics Communications, JPCO-101816.R1 (2021)

Abstract: Low-frequency noise is one of the important characteristics of 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) that is susceptible to oxide traps. Drain-source voltage noise models of 4H-SiC MOSFETs under low–drain-voltage and inverse condition were proposed by considering the spatial and energy non-uniform distribution of the oxide trap, based on the McWhoter model for uniform trap distribution. This study performed noise experiments on commercial 4H-SiC MOSFETs, and revealed that the non-uniform spatial and non-uniform energy distribution caused new 1/f noise phenomenon, different from that under uniform spatial and energy distribution. By combining experimental data and theoretical models, the spatial and energy distribution of oxide traps of these samples were determined.

Fig: Adaptive circuit for 4H-SiC MOSFET noise measurement

in the frequency 1 Hz-10kHz ranged

[paper] Ultra-High Voltage SiC IGBT

Wide-Range Prediction of Ultra-High Voltage SiC IGBT Static Performance

Using Calibrated TCAD Model

Daniel Johannesson^1,2, Keijo Jacobs¹, Staffan Norrga¹, Anders Hallén³, 

Muhammad Nawaz² and Hans-Peter Nee^1,2

Materials Science Forum Submitted: 2019-09-19

ISSN: 1662-9752, Vol. 1004, pp 911-916  

DOI:10.4028/www.scientific.net/MSF.1004.911

¹Division of Electric Power and Energy Systems, KTH , Sweden
²ABB Corporate Research, Västerås, Sweden
³Division of Electronics, KTH, Sweden

Abstract: In this paper, a technology computer-aided design (TCAD) model of a silicon carbide (SiC) insulated-gate bipolar transistor (IGBT) has been calibrated against previously reported experimental data. The calibrated TCAD model has been used to predict the static performance of theoretical SiC IGBTs with ultra-high blocking voltage capabilities in the range of 20-50 kV. The simulation results of transfer characteristics, IC-VGE, forward characteristics, IC-VCE, and blocking voltage characteristics are studied. The threshold voltage is approximately 5 V, and the forward voltage drop is ranging from VF = 4.2-10.0 V at IC = 20 A, using a charge carrier lifetime of τA = 20 μs. Furthermore, the forward voltage drop impact for different process dependent parameters (i.e., carrier lifetimes, mobility/scattering and trap related defects) and junction temperature are investigated in a parametric sensitivity analysis. The wide-range simulation results may be used as an input to facilitate high power converter design and evaluation. In this case, the TCAD simulated static characteristics of SiC IGBTs is compared to silicon (Si) IGBTs in a modular multilevel converter in a general highpower application. The results indicate several benefits and lower conduction energy losses using ultra-high voltage SiC IGBTs compared to Si IGBTs.

Fig: 4H-SiC IGBT structure implemented in 2D TCAD simulator

Acknowledgment This work was funded through SweGRIDS, by the Swedish Energy Agency and ABB.

[paper] Graphene/4H-SiC/Graphene MSM UV-photodetector

An optimized Graphene/4H-SiC/Graphene MSM UV-photodetector operating
in a wide range of temperature 

H. Bencherif ¹, L. Dehimi1 ², G. Messina ³, P. Vincent ⁴, F. Pezzimenti ³, F. G. Della Corte ^{3 1}Laboratory of Metallic and Semiconductor Materials, University of Biskra, Biskra, DZ

²Faculty of Science, University of Batna 1, DZ

³DIIES, Mediterranea University of Reggio Calabria, Reggio Calabria, IT

⁴School of Electronics Engineering, KNU, 80 Daehakro, Buk-gu, Daegu, 702-701, KP

Abstract: In this paper, .an accurate analytical model has been developed to optimize the performance of an Interdigitated Graphene Electrode/p-silicon carbide (IGE/p-4H-SiC) Metal semiconductor Metal (MSM) photodetector operating in a wide range of temperatures. The proposed model considers different carrier loss mechanisms and can reproduce the experimental results well. An overall assessment of the electrodes geometrical parameters’ influence on the device sensitivity and speed performances was executed. Our results confirm the excellent ability of the suggested Graphene electrode system to decrease the unwanted shadowing effect. A responsivity of 238 μA/W was obtained under 325-nm illumination compared to the 16.7 μA/W for the conventional Cr-Pd/p-SiC PD. A photocurrent to- dark-current ratio (PDCR) of 5.75 × 105 at 300K and 270 at 500K was distinguished. The response time was found to be around 14 μs at 300K and 54.5 μs at 500K. Furthermore, the developed model serves as a fitness function for the multi objective optimization (MOGA) approach. The optimized IGE/p-4H-SiC MSM-PD design not only exhibits higher performance in terms of PDCR (7.2×105), responsivity (430A/cm2) and detectivity (1.3×1014 Jones) but also balances the compromise between ultrasensitive and high-speed figures of merit with a response time of 4.7 μs. Therefore, the proposed methodology permits to realize ultra-sensitive, high-speed SiC optoelectronic devices for extremely high temperature applications. 

FIG: a) Energy band diagram of Graphene/p-SiC/Graphene structure, b) Cross-sectional view of the suggested IGE/4H-SiC MSM UV-PD with interdigitated electrodes

Acknowledgments: This work was supported by DGRSDT Of Ministry of Higher education of Algeria. The work was done in the unit of research of materials and renewable energies (URMER).