Study on Electric Field Modulation and Avalanche Enhancement of SiC/GaN IMPATT Diode

This paper proposes a 6H-materials silicon carbide (SiC)/gallium nitride (GaN) heterogeneous p-n structure to replace the GaN homogenous p-n junction to manufacture an impact-ionization-avalanche-transit-time (IMPATT) diode, and the performance of this 6H-SiC/GaN heterojunction single-drift-region (SDR) IMPATT diode is simulated at frequencies above 100 GHz. The performance parameters of the studied device were simulated and compared with the conventional GaN p-n IMPATT diode. The results show that the p-SiC/n-GaN IMPATT performance is significantly improved, and this is reflected in the enhanced characteristics in terms of operating frequency, rf power, and dc-rf conversion efficiency by the two mechanisms. One such characteristic that the new structure has an excessive avalanche injection of electrons in the p-type SiC region owing to the ionization characteristics of the SiC material, while another is a lower electric field distribution in the drift region, which can induce a higher electron velocity and larger current in the structure. The work provides a reference to obtain a deeper understanding of the mechanism and design of IMPATT devices based on wide-bandgap semiconductor materials.

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Study of p-SiC/n-GaN Hetero-Structural Double-Drift Region IMPATT Diode

Micromachines ◽

10.3390/mi12080919 ◽

2021 ◽

Vol 12 (8) ◽

pp. 919

Author(s):

Yang Dai ◽

Qingsong Ye ◽

Jiangtao Dang ◽

Zhaoyang Lu ◽

Weiwei Zhang ◽

...

Keyword(s):

Impact Ionization ◽

Wide Bandgap ◽

Drift Region ◽

Rf Power ◽

Large Signal ◽

Impatt Diode ◽

Signal Characteristics ◽

Design And Manufacture ◽

First Time ◽

Ddr Impatt

Nowadays, the immature p-GaN processes cannot meet the manufacturing requirements of GaN impact ionization avalanche transit time (IMPATT) diodes. Against this backdrop, the performance of wide-bandgap p-SiC/n-GaN heterojunction double-drift region (DDR) IMPATT diode is investigated in this paper for the first time. The direct-current (DC) steady-state, small-signal and large-signal characteristics are numerically simulated. The results show that compared with the conventional GaN single-drift region (SDR) IMPATT diode, the performance of the p-SiC/n-GaN DDR IMPATT proposed in this design, such as breakdown voltage, negative conductance, voltage modulation factor, radio frequency (RF) power and DC-RF conversion efficiency have been significantly improved. At the same time, the structure proposed in this design has a larger frequency bandwidth. Due to its greater potential in the RF power density, which is 1.97 MW/cm2 in this study, indicates that the p-SiC/n-GaN heterojunction provides new possibilities for the design and manufacture of IMPATT diode.

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A SiC LDMOS with electric field modulation by a step compound drift region

Superlattices and Microstructures ◽

10.1016/j.spmi.2018.04.046 ◽

2018 ◽

Vol 119 ◽

pp. 94-102 ◽

Cited By ~ 3

Author(s):

Meng-tian Bao ◽

Ying Wang ◽

Cheng-hao Yu ◽

Fei Cao

Keyword(s):

Electric Field ◽

Drift Region ◽

Field Modulation

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Ion-Induced Anomalous Charge Collection Mechanisms in SiC Schottky Barrier Diodes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.821-823.575 ◽

2015 ◽

Vol 821-823 ◽

pp. 575-578 ◽

Cited By ~ 1

Author(s):

Takahiro Makino ◽

Manato Deki ◽

Shinobu Onoda ◽

Norihiro Hoshino ◽

Hidekazu Tsuchida ◽

...

Keyword(s):

Electric Field ◽

Schottky Barrier ◽

Layer Thickness ◽

Epitaxial Layer ◽

Impact Ionization ◽

Heavy Ion ◽

Charge Collection ◽

Static Electric Field ◽

The Impact ◽

Lower Electric Field

The charge induced in SiC-SBDs with different epi-layer thicknesses by ion incidence was measured to understand the mechanism of heavy-ion-induced anomalous charge collection in SiC-SBDs. SiC SBD of which epitaxial-layer thicknesses is close to ion range show larger anomalous charge collection than SBD with thicker epi-layer although the former one has lower electric field than the later one. The gains of collected charge from the SBDs suggest that the impact ionization under 0.16 - 0.18 MV/cm of the static electric field in depletion layer is not dominant mechanisms for the anomalous charge collection. It is suggested that the epitaxial-layer thickness and ion-induced transient high electric field are key to understand the anomalous charge collection mechanisms in SBDs.

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Comparison of drift–diffusion model and hydrodynamic carrier transport model for simulation of GaN-based IMPATT diodes

Modern Physics Letters B ◽

10.1142/s0217984919501562 ◽

2019 ◽

Vol 33 (13) ◽

pp. 1950156 ◽

Cited By ~ 1

Author(s):

Xiusheng Li ◽

Lin’an Yang ◽

Xiaohua Ma

Keyword(s):

Electric Field ◽

Diffusion Model ◽

Carrier Transport ◽

Impact Ionization ◽

Transport Model ◽

Relaxation Effect ◽

Drift Diffusion Model ◽

Drift Diffusion ◽

Impatt Diode ◽

The Impact

This paper presents a numerical simulation of a Wurtzite-GaN-based IMPATT diode operating at the low-end frequency of terahertz range. Conventional classical drift–diffusion model is independent of the energy relaxation effect at high electric field. However, in this paper, a hydrodynamic carrier transport model including a new energy-based impact ionization model is used to investigate the dc and high-frequency characteristics of an IMPATT diode with a traditional drift–diffusion model as comparison. Simulation results show that the maximum rf power density and the dc-to-rf conversion efficiency are larger for conventional drift–diffusion model because it overestimates the impact ionization rate. Through hydrodynamic simulation we revealed that the impact ionization rates are seriously affected by the high and rapidly varied electric field and the electron energy relaxation effect, which lead to the rf output power density and the dc-to-rf conversion efficiency falls gradually, and a wider operation frequency band is obtained compared with the drift–diffusion model simulation at frequencies over 310 GHz.

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Improving Linearity and Robustness of RF LDMOS by Mitigating Quasi-Saturation Effect

Active and Passive Electronic Components ◽

10.1155/2019/8425198 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7

Author(s):

Haifeng Mo ◽

Yaohui Zhang ◽

Helun Song

Keyword(s):

Electric Field ◽

Electron Velocity ◽

Drift Region ◽

Electron Hole ◽

Velocity Saturation ◽

Root Cause ◽

Turn On ◽

Saturation Region ◽

First Time ◽

Peak Electric Field

This paper discusses linearity and robustness together for the first time, disclosing a way to improve them. It reveals that the nonlinear transconductance with device working at quasi-saturation region is significant factor of device linearity. The peak electric field is the root cause of electron velocity saturation. The high electric field at the drift region near the drain will cause more electron-hole pairs generated to trigger the parasitic NPN transistor turn-on, which may cause failure of device. Devices with different drift region doping are simulated with TCAD and measured. With LDD4 doping, the peak electric field in the drift region is reduced; the linear region of the transconductance is broadened. The adjacent channel power ratio is decreased by 2 dBc; 12% more power can be discharged before the NPN transistor turn-on, indicating a better linearity and robustness.

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Prospects of 4H-SiC Double Drift Region IMPATT Device as a Photo-Sensitive High-Power Source at 0.7 Terahertz Frequency Regime

Active and Passive Electronic Components ◽

10.1155/2008/275357 ◽

2008 ◽

Vol 2008 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

Moumita Mukherjee ◽

Nilratan Mazumder ◽

Sitesh Kumar Roy

Keyword(s):

High Power ◽

Dynamic Performance ◽

Negative Resistance ◽

Wide Bandgap ◽

Drift Region ◽

Terahertz Frequency ◽

Impatt Diode ◽

Terahertz Region ◽

Frequency Regime ◽

First Time

The dynamic performance of wide-bandgap 4H-SiC based double drift region (p++ p n n++) IMPATT diode is simulated for the first time at terahertz frequency (0.7 Terahertz) region. The simulation experiment establishes the potential of SiC based IMPATT diode as a high power (2.5×1011 Wm−2) terahertz source. The parasitic series resistance in the device is found to reduce the RF power output by 10.7%. The effects of external radiation on the simulated diode are also studied. It is found that (i) the negative conductance and (ii) the negative resistance of the diode decrease, while, the frequency of operation and the quality factor shift upward under photoillumination. Holes in 4H-SiC based IMPATT are found to dominate the modulation activities. The inequality in the magnitude of electron and hole ionization rates in the semiconductors may be correlated with these findings.

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