III–V Compound Semiconductors and Devices

A special issue of Micromachines (ISSN 2072-666X). This special issue belongs to the section "D1: Semiconductor Devices".

Deadline for manuscript submissions: closed (3 April 2023) | Viewed by 28398

Special Issue Editors


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Institute of Microelectronics, National Cheng Kung University, Tainan 70101, Taiwan
Interests: semiconductor devices and physics
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Department of Electronic Engineering, I-Shou University, Kaohsiung 84001, Taiwan
Interests: metal-oxide-semiconductor technology; high-speed semiconductor devices; semiconductor manufacturing technology
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Compared to silicon technology, III-V compound semiconductors and their applications have attracted considerable attention for use in many different circuits such as power amplifiers, low-noise amplifiers, mixers, frequency converters, phase shifters, and optoelectronics.

This Special Issue of Micromachines aims to present recent advantages in the fabrication, characterization, and modeling of electron devices based on III-V compound semiconductors and devices. The scope of this Special Issue covers, but is not limited to:

  • Characterization techniques for defects in high-k dielectrics/III-V semiconductors.
  • Novel methods or concepts for III-V devices (e.g., HBT, field-effect transistors, nanowires, or gate-all-around).
  • Electronic or optoelectronic applications for III-V devices (including physical, chemical, and electronic properties).
  • Advanced fabrication processes for III-V on insulator (e.g., GaN on silicon or III-V on silicon).
  • Advanced simulation or modeling of III-V devices.

Prof. Dr. Yeong-Her Wang
Prof. Dr. Kuan-Wei Lee
Guest Editors

Manuscript Submission Information

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Keywords

  • compound semiconductor
  • high-k dielectric
  • insulator
  • frequency
  • optoelectronic

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Published Papers (14 papers)

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Research

12 pages, 2812 KiB  
Communication
In Situ H-Radical Surface Treatment on Aluminum Gallium Nitride for High-Performance Aluminum Gallium Nitride/Gallium Nitride MIS-HEMTs Fabrication
by Yannan Yang, Rong Fan, Penghao Zhang, Luyu Wang, Maolin Pan, Qiang Wang, Xinling Xie, Saisheng Xu, Chen Wang, Chunlei Wu, Min Xu, Jian Jin and David Wei Zhang
Micromachines 2023, 14(7), 1278; https://doi.org/10.3390/mi14071278 - 21 Jun 2023
Cited by 1 | Viewed by 1432
Abstract
In this work, we demonstrated a low current collapse normally on Al2O3/AlGaN/GaN MIS-HEMT with in situ H-radical surface treatment on AlGaN. The in situ atomic pretreatment was performed in a specially designed chamber prior to the thermal ALD-Al2 [...] Read more.
In this work, we demonstrated a low current collapse normally on Al2O3/AlGaN/GaN MIS-HEMT with in situ H-radical surface treatment on AlGaN. The in situ atomic pretreatment was performed in a specially designed chamber prior to the thermal ALD-Al2O3 deposition, which improved the Al2O3/AlGaN interface with Dit of ~2 × 1012 cm−2 eV−1, and thus effectively reduced the current collapse and the dynamic Ron degradation. The devices showed good electrical performance with low Vth hysteresis and peak trans-conductance of 107 mS/mm. Additionally, when the devices operated under 25 °C pulse-mode stress measurement with VDS,Q = 40 V (period of 1 ms, pulse width of 1 μs), the dynamic Ron increase of ~14.1% was achieved. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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10 pages, 4010 KiB  
Article
Study on P-AlGaAs/Al/Au Ohmic Contact Characteristics for Improving Optoelectronic Response of Infrared Light-Emitting Device
by Hyung-Joo Lee, Jae-Sam Shim, Jin-Young Park, Lee-Ku Kwac and Chang-Ho Seo
Micromachines 2023, 14(5), 1053; https://doi.org/10.3390/mi14051053 - 16 May 2023
Viewed by 1900
Abstract
The Al/Au alloy was investigated to improve the ohmic characteristic and light efficiency of reflective infrared light-emitting diodes (IR-LEDs). The Al/Au alloy, which was fabricated by combining 10% aluminum and 90% gold, led to considerably improved conductivity on the top layer of p-AlGaAs [...] Read more.
The Al/Au alloy was investigated to improve the ohmic characteristic and light efficiency of reflective infrared light-emitting diodes (IR-LEDs). The Al/Au alloy, which was fabricated by combining 10% aluminum and 90% gold, led to considerably improved conductivity on the top layer of p-AlGaAs of the reflective IR-LEDs. In the wafer bond process required for fabricating the reflective IR-LED, the Al/Au alloy, which has filled the hole patterns in Si3N4 film, was used for improving the reflectivity of the Ag reflector and was bonded directly to the top layer of p-AlGaAs on the epitaxial wafer. Based on current-voltage measurements, it was found that the Al/Au alloyed material has a distinct ohmic characteristic pertaining to the p-AlGaAs layer compared with those of the Au/Be alloy material. Therefore, the Al/Au alloy may constitute one of the favored approaches for overcoming the insulative reflective structures of reflective IR-LEDs. For a current density of 200 mA, a lower forward voltage (1.56 V) was observed from the wafer bond IR-LED chip made with the Al/Au alloy; this voltage was remarkably lower in value than that of the conventional chip made with the Au/Be metal (2.29 V). A higher output power (182 mW) was observed from the reflective IR-LEDs made with the Al/Au alloy, thus displaying an increase of 64% compared with those made with the Au/Be alloy (111 mW). Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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12 pages, 2580 KiB  
Article
A New Analytical Large-Signal Model for Quasi-Ballistic Transport in InGaAs HEMTs Accommodating Dislocation Scattering
by Jinye Wang, Jun Liu, Jie Wang and Zhenxin Zhao
Micromachines 2023, 14(5), 1023; https://doi.org/10.3390/mi14051023 - 10 May 2023
Cited by 1 | Viewed by 1281
Abstract
A surface-potential-based analytical large-signal model, which is applicable to both ballistic and quasi-ballistic transport in InGaAs high electron mobility transistors, is developed. Based on the one-flux method and a new transmission coefficient, a new two-dimensional electron gas charge density is derived, while the [...] Read more.
A surface-potential-based analytical large-signal model, which is applicable to both ballistic and quasi-ballistic transport in InGaAs high electron mobility transistors, is developed. Based on the one-flux method and a new transmission coefficient, a new two-dimensional electron gas charge density is derived, while the dislocation scattering is novelly taken into account. Then, a unified expression for Ef valid in all the regions of gate voltages is determined, which is utilized to directly calculate the surface potential. The flux is used to derive the drain current model incorporating important physical effects. Moreover, the gate-source capacitance Cgs and gate-drain capacitance Cgd are obtained analytically. The model is extensively validated with the numerical simulations and measured data of the InGaAs HEMT device with the gate length of 100 nm. The model is in excellent agreement with the measurements under I-V, C-V, small-signal conditions, and large-signal conditions. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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9 pages, 3495 KiB  
Article
Near-Full Current Dynamic Range THz Quantum Cascade Laser Frequency Comb
by Yu Ma, Weijiang Li, Yuanyuan Li, Junqi Liu, Ning Zhuo, Ke Yang, Jinchuan Zhang, Shenqiang Zhai, Shuman Liu, Lijun Wang and Fengqi Liu
Micromachines 2023, 14(2), 473; https://doi.org/10.3390/mi14020473 - 18 Feb 2023
Cited by 1 | Viewed by 1470
Abstract
The present study proposes a terahertz quantum cascade laser frequency comb (THz QCL FC) with a semi-insulated surface plasma waveguide characterized by a low threshold current density, high power and a wide current dynamic range. The gain dispersion value and the nonlinear susceptibility [...] Read more.
The present study proposes a terahertz quantum cascade laser frequency comb (THz QCL FC) with a semi-insulated surface plasma waveguide characterized by a low threshold current density, high power and a wide current dynamic range. The gain dispersion value and the nonlinear susceptibility were optimized based on the combination of a hybrid bound-to-continuum active region with a semi-insulated surface plasmon waveguide. Without any extra dispersion compensator, stable frequency comb operation within a current dynamic range of more than 97% of the total was revealed by the intermode beat note map. Additionally, a total comb spectral emission of about 300 GHz centered around 4.6 THz was achieved for a 3 mm long and 150 µm wide device. At 10 K, a maximum output power of 22 mW was obtained with an ultra-low threshold current density of 64.4 A·cm−2. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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13 pages, 8565 KiB  
Article
A Simulation Optimization Factor of Si(111)-Based AlGaN/GaN Epitaxy for High Frequency and Low-Voltage-Control High Electron Mobility Transistor Application
by He Guan, Guiyu Shen, Shibin Liu, Chengyu Jiang and Jingbo Wu
Micromachines 2023, 14(1), 168; https://doi.org/10.3390/mi14010168 - 9 Jan 2023
Cited by 1 | Viewed by 1857
Abstract
The effects of barrier layer thickness, Al component of barrier layer, and passivation layer thickness of high-resistance Si (111)-based AlGaN/GaN heterojunction epitaxy on the knee-point voltage (Vknee), saturation current density (Id-sat), and cut-off frequency (ft [...] Read more.
The effects of barrier layer thickness, Al component of barrier layer, and passivation layer thickness of high-resistance Si (111)-based AlGaN/GaN heterojunction epitaxy on the knee-point voltage (Vknee), saturation current density (Id-sat), and cut-off frequency (ft) of its high electron mobility transistor (HEMT) are simulated and analyzed. A novel optimization factor OPTIM is proposed by considering the various performance parameters of the device to reduce the Vknee and improve the Id-sat on the premise of ensuring the ft. Based on this factor, the optimized AlGaN/GaN epitaxial structure was designed with a barrier layer thickness of 20 nm, an Al component in the barrier layer of 25%, and a SiN passivation layer of 6 nm. By simulation, when the gate voltage Vg is 0 V, the designed device with a gate length of 0.15 μm, gate-source spacing of 0.5 μm, and gate-drain spacing of 1 μm presents a high Id-sat of 750 mA/mm and a low Vknee of 2.0 V and presents ft and maximum frequency (fmax) as high as 110 GHz and 220 GHz, respectively. The designed device was fabricated and tested to verify the simulation results. We demonstrated the optimization factor OPTIM can provide an effective design method for follow-up high-frequency and low-voltage applications of GaN devices. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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13 pages, 3459 KiB  
Article
Design and Manufacture of Millimeter-Scale 3D Transformers for RF-IC
by Haiwang Li, Kaiyun Zhu, Tiantong Xu, Kaibo Lei and Jingchao Xia
Micromachines 2022, 13(12), 2162; https://doi.org/10.3390/mi13122162 - 7 Dec 2022
Cited by 3 | Viewed by 1983
Abstract
The development of radio-frequency integrated circuits (RF-IC) necessitates higher requirements for the size of microtransformers. This paper describes millimeter-scale 3D transformers in millimeter-scale, solenoidal, and toroidal transformers manufactured using Micro-electromechanical Systems (MEMS). Two through-silicon via (TSV) copper coils with a high aspect ratio [...] Read more.
The development of radio-frequency integrated circuits (RF-IC) necessitates higher requirements for the size of microtransformers. This paper describes millimeter-scale 3D transformers in millimeter-scale, solenoidal, and toroidal transformers manufactured using Micro-electromechanical Systems (MEMS). Two through-silicon via (TSV) copper coils with a high aspect ratio are precisely interleaved on a reserved air core (magnet core cavity) with a vertical height of over 1 mm because of the thickness of the substrate, which increases the performance while reducing the footprint. The effects of the wire width, coil turns, magnetic core, and substrate on the performance of the two transformers are discussed through numerical simulations. When an air core is present, solenoidal transformers are better than toroidal transformers in terms of performance and footprint; however, the gap decreases when the size is reduced. Additionally, the magnetic core significantly improves the performance of the toroidal transformer compared to that of the solenoid. Thus, the toroidal transformer has a higher potential for further size reduction. The two types of transformers were then manufactured completely using MEMS and electroplating. This paper discusses the influence of various parameters on millimeter-scale 3D transformers and realizes processing in silicon, which provides the foundation for integrating transformers in a chip. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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12 pages, 6759 KiB  
Article
C-Band 30 W High PAE Power Amplifier MMIC with Second Harmonic Suppression for Radar Network Application
by Fan Yang, Leijun Song and Yuehang Xu
Micromachines 2022, 13(12), 2079; https://doi.org/10.3390/mi13122079 - 26 Nov 2022
Cited by 8 | Viewed by 2424
Abstract
In order to meet the application requirements of radar networks for high efficiency and high second harmonic suppression (SHS) of power amplifiers, this paper proposes a C-band 30 W power amplifier (PA) microwave monolithic integrated circuit (MMIC) based on 0.25 μm gallium nitride [...] Read more.
In order to meet the application requirements of radar networks for high efficiency and high second harmonic suppression (SHS) of power amplifiers, this paper proposes a C-band 30 W power amplifier (PA) microwave monolithic integrated circuit (MMIC) based on 0.25 μm gallium nitride (GaN) high electron mobility transistor (HEMT) process. The proposed PA uses a two-stage amplifier structure to achieve high power gain. A topology with SHS is designed in the output-matching network. Besides, the large signal model load pull simulation and the harmonic control technology in the output stage are used to improve efficiency. The high-power additional efficiency (PAE) and high SHS of the PA MMIC are achieved simultaneously. In the 5–6 GHz frequency range, multiple indicator measurements of the proposed PA show that output power is over 45 dBm, the PAE is more than 57%, the SHS exceeds 45 dBc, the power gain is greater than 24 dB, which are conducted under the condition of 100 μs pulse width and 10% duty cycle. In addition, the size of the PA MMIC, including bonding pads, is 3.3 × 3.1 mm2. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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13 pages, 3290 KiB  
Article
Electrical Performance of 28 nm-Node Varying Channel-Width nMOSFETs under DPN Process Treatments
by Shou-Yen Chao, Wen-How Lan, Shou-Kong Fan, Zi-Wen Zhon and Mu-Chun Wang
Micromachines 2022, 13(11), 1861; https://doi.org/10.3390/mi13111861 - 29 Oct 2022
Cited by 4 | Viewed by 2181
Abstract
The decoupled-plasma nitridation treatment process is an effective recipe for repairing the trap issues when depositing high-k gate dielectric. Because of this effect, electrical performance is not only increased with the relative dielectric constant, but there is also a reduction in gate leakage. [...] Read more.
The decoupled-plasma nitridation treatment process is an effective recipe for repairing the trap issues when depositing high-k gate dielectric. Because of this effect, electrical performance is not only increased with the relative dielectric constant, but there is also a reduction in gate leakage. In the past, the effect of nitridation treatment on channel-length was revealed, but a channel-width effect with that treatment was not found. Sensing the different nano-node channel-width n-channel MOSFETs, the electrical characteristics of these test devices with nitridation treatments were studied and the relationship among them was analyzed. Based on measurement of the VT, SS, Gm, ION, and IOFF values of the tested devices, the electrical performance of them related to process treatment is improved, including the roll-off effect of channel-width devices. On the whole, the lower thermal budget in nitridation treatment shows better electrical performance for the tested channel-width devices. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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11 pages, 4509 KiB  
Article
High-Speed Shift Register with Dual-Gated Thin-Film Transistors for a 31-Inch 4K AMOLED Display
by Rong Song, Yonghe Wu, Chengkai Lin, Kai Liu, Zhenjun Qing, Yingxiang Li and Yan Xue
Micromachines 2022, 13(10), 1696; https://doi.org/10.3390/mi13101696 - 9 Oct 2022
Cited by 3 | Viewed by 1866
Abstract
In this work, a promising dual-gated thin film transistor (TFT) structure has been proposed and introduced in the shift register (SR)-integrated circuits to reduce the rising time. The threshold voltage can be simultaneously changed by the top gate and the bottom gate in [...] Read more.
In this work, a promising dual-gated thin film transistor (TFT) structure has been proposed and introduced in the shift register (SR)-integrated circuits to reduce the rising time. The threshold voltage can be simultaneously changed by the top gate and the bottom gate in the proposed dual-gated TFTs. When the SR circuits start to export the scan signals in the displays, the driving currents in the SR circuits are increased by switching the working station of driving TFTs from the enhancement characterization to the depletion characterization. Subsequently, the detailed smart spice simulation has been used to study the function of the proposed SR circuits. In the next step, the proposed SR circuits have been fabricated in a G4.5 active-matrix organic light-emitting diode manufacture factory. The simulated and experimental results indicate that the shift register pulses with the full swing amplitude can be obtained in the SR circuits. Moreover, in contrast to the conventional SR circuits employing with the single-gated TFTs, it has been found that the rising time of the output signals can be reduced from 3.75 μs to 1.23 μs in the proposed SR circuits with the dual-gated TFTs, thus exhibiting the significant improvement of the driving force in the proposed SR circuits. Finally, we demonstrated a 31-inch 4K AMOLED display with the proposed SR circuits. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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6 pages, 3076 KiB  
Article
Low Buffer Trapping Effects above 1200 V in Normally off GaN-on-Silicon Field Effect Transistors
by Idriss Abid, Youssef Hamdaoui, Jash Mehta, Joff Derluyn and Farid Medjdoub
Micromachines 2022, 13(9), 1519; https://doi.org/10.3390/mi13091519 - 14 Sep 2022
Cited by 1 | Viewed by 2038
Abstract
We report on the fabrication and electrical characterization of AlGaN/GaN normally off transistors on silicon designed for high-voltage operation. The normally off configuration was achieved with a p-gallium nitride (p-GaN) cap layer below the gate, enabling a positive threshold voltage higher than +1 [...] Read more.
We report on the fabrication and electrical characterization of AlGaN/GaN normally off transistors on silicon designed for high-voltage operation. The normally off configuration was achieved with a p-gallium nitride (p-GaN) cap layer below the gate, enabling a positive threshold voltage higher than +1 V. The buffer structure was based on AlN/GaN superlattices (SLs), delivering a vertical breakdown voltage close to 1.5 kV with a low leakage current all the way to 1200 V. With the grounded substrate, the hard breakdown voltage transistors at VGS = 0 V is 1.45 kV, corresponding to an outstanding average vertical breakdown field higher than 2.4 MV/cm. High-voltage characterizations revealed a state-of-the-art combination of breakdown voltage at VGS = 0 V together with low buffer electron trapping effects up to 1.4 kV, as assessed by means of substrate ramp measurements. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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11 pages, 3342 KiB  
Article
A Novel L-Gate InGaAs/GaAsSb TFET with Improved Performance and Suppressed Ambipolar Effect
by Boyang Ma, Shupeng Chen, Shulong Wang, Tao Han, Hao Zhang, Chenyu Yin, Yaolin Chen and Hongxia Liu
Micromachines 2022, 13(9), 1474; https://doi.org/10.3390/mi13091474 - 5 Sep 2022
Cited by 3 | Viewed by 1880
Abstract
A heterojunction tunneling field effect transistor with an L-shaped gate (HJ-LTFET), which is very applicable to operate at low voltage, is proposed and studied by TCAD tools in this paper. InGaAs/GaAsSb heterojunction is applied in HJ-LTFET to enhance the ON-state current (ION [...] Read more.
A heterojunction tunneling field effect transistor with an L-shaped gate (HJ-LTFET), which is very applicable to operate at low voltage, is proposed and studied by TCAD tools in this paper. InGaAs/GaAsSb heterojunction is applied in HJ-LTFET to enhance the ON-state current (ION). Owing to the quasi-broken gap energy band alignment of InGaAs/GaAsSb heterojunction, height and thickness of tunneling barrier are greatly reduced. However, the OFF-state leakage current (IOFF) also increases significantly due to the reduced barrier height and thickness and results in an obvious source-to-drain tunneling (SDT). In order to solve this problem, an HfO2 barrier layer is inserted between source and drain. Result shows that the insertion layer can greatly suppress the horizontal tunneling leakage appears at the source and drain interface. Other optimization studies such as work function modulation, doping concentration optimization, scaling capability, and analog/RF performance analysis are carried out, too. Finally, the HJ-LTFET with a large ION of 213 μA/μm, a steep average SS of 8.9 mV/dec, and a suppressed IOFF of 10−12 μA/μm can be obtained. Not only that, but the fT and GBP reached the maximum values of 68.3 GHz and 7.3 GHz under the condition of Vd = 0.5 V, respectively. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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13 pages, 3789 KiB  
Article
Study of High-Performance GaN-Based Trench CAVET with Stepped Doping Microstructure
by Yuan Li, Liang Xu, Zhiyou Guo and Huiqing Sun
Micromachines 2022, 13(8), 1273; https://doi.org/10.3390/mi13081273 - 7 Aug 2022
Cited by 2 | Viewed by 2121
Abstract
In this article, an innovative GaN-based trench current-aperture vertical electron transistor (CAVET) with a stepped doping microstructure is proposed and studied using Silvaco-ATLAS. According to the simulation and analyzed characteristics, the best performance renders a remarkable Baliga’s figure of merit (FOM) of 4.767 [...] Read more.
In this article, an innovative GaN-based trench current-aperture vertical electron transistor (CAVET) with a stepped doping microstructure is proposed and studied using Silvaco-ATLAS. According to the simulation and analyzed characteristics, the best performance renders a remarkable Baliga’s figure of merit (FOM) of 4.767 GW·cm2 owing to the modulation of the electric-field distribution. By adjusting the size of the stepped doping microstructure and doping concentration in the GaN drift, the maximum optimized result can achieve a relatively high breakdown voltage (BV) of 2523 V with a very low specific on-resistance (Ron,sp) of 1.34 mΩ·cm2, or the BV can be improved to 3024 V with a specific on-resistance (Ron,sp) of 2.08 mΩ·cm2. Compared with the conventional superjunction GaN-based trench CAVET, the newly demonstrated structure can achieve a 43% reduction in Ron,sp and increase by almost 20% the original BV. These results indicate the superiority of using the stepped doping microstructure in a trench CAVET to improve the BV and decrease Ron,sp, providing a reference for further development of GaN-based CAVETs. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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13 pages, 4037 KiB  
Article
Reduction in RF Loss Based on AlGaN Back-Barrier Structure Changes
by Yi Fang, Ling Chen, Yuqi Liu and Hong Wang
Micromachines 2022, 13(6), 830; https://doi.org/10.3390/mi13060830 - 26 May 2022
Cited by 3 | Viewed by 2265
Abstract
We designed a high electron mobility transistor (HEMT) epitaxial structure based on an AlGaN/GaN heterojunction, utilizing Silvaco TCAD, and selected AlGaN with an aluminum composition of 0.1 as the back-barrier of the AlGaN/GaN heterojunction. We enhanced the confinement of the two-dimensional electron gas [...] Read more.
We designed a high electron mobility transistor (HEMT) epitaxial structure based on an AlGaN/GaN heterojunction, utilizing Silvaco TCAD, and selected AlGaN with an aluminum composition of 0.1 as the back-barrier of the AlGaN/GaN heterojunction. We enhanced the confinement of the two-dimensional electron gas (2DEG) by optimizing the structural parameters of the back barrier, so that the leakage current of the buffer layer is reduced. Through these optimization methods, a lower drain leakage current and a good radio frequency performance were obtained. The device has a cut-off frequency of 48.9 GHz, a maximum oscillation frequency of 73.20 GHz, and a radio frequency loss of 0.239 dB/mm (at 6 GHz). This work provides a basis for the preparation of radio frequency devices with excellent frequency characteristics and low RF loss. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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8 pages, 3099 KiB  
Article
Off-State Performance Characterization of an AlGaN/GaN Device via Artificial Neural Networks
by Jing Chen, Yufeng Guo, Jun Zhang, Jianhua Liu, Qing Yao, Jiafei Yao, Maolin Zhang and Man Li
Micromachines 2022, 13(5), 737; https://doi.org/10.3390/mi13050737 - 5 May 2022
Viewed by 1882
Abstract
Due to the complexity of the 2D coupling effects in AlGaN/GaN HEMTs, the characterization of a device’s off-state performance remains the main obstacle to exploring the device’s breakdown characteristics. To predict the off-state performance of AlGaN/GaN HEMTs with efficiency and veracity, an artificial [...] Read more.
Due to the complexity of the 2D coupling effects in AlGaN/GaN HEMTs, the characterization of a device’s off-state performance remains the main obstacle to exploring the device’s breakdown characteristics. To predict the off-state performance of AlGaN/GaN HEMTs with efficiency and veracity, an artificial neural network-based methodology is proposed in this paper. Given the structure parameters, the off-state current–voltage (I–V) curve can therefore be obtained along with the essential performance index, such as breakdown voltage (BV) and saturation leakage current, without any physics domain requirement. The trained neural network is verified by the good agreement between predictions and simulated data. The proposed tool can achieve a low average error of the off-state I–V curve prediction (Ave. Error < 5%) and consumes less than 0.001‰ of average computing time than in TCAD simulation. Meanwhile, the convergence issue of TCAD simulation is avoided using the proposed method. Full article
(This article belongs to the Special Issue III–V Compound Semiconductors and Devices)
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