• Journal of IKEEE
• /
• v.23 no.3
• /
• pp.832-838
• /
• 2019

In this paper, 4H-SiC MOSFET, the next generation power semiconductor device, was studied. In particular, Semi-SJ MOSFET structures with improved electrical characteristics than conventional DMOSFET structures were proposed in the class of 3300V, and static characteristics of conventional and proposed structures were compared and analyzed through TCAD simulations. Semi-SuperJunction MOSFET structure is partly structure that introduces SuperJunction, improves Electric field distribution through the two-dimensional depletion effect, and increases breakdown voltage. Benefit from the improvement of breakdown voltage, which can improve the on resistance as high doping is possible. The proposed structure has a slight reduction in breakdown voltage, but has an 80% decrease in on resistance compared to the conventional DMOSFET structure, and a 44% decrease in on resistance compared to the Current Spreading Layer(CSL) structure that improves the conventional DMOSFET structure.

• Proceedings of the KIPE Conference
• /
• 2014.11a
• /
• pp.85-86
• /
• 2014

The paper presents a power supply of atmospheric-pressure plasma reactor based on SiC (Silicon Carbide) MOSFET resonant inverter. Thanks to the capacitive characteristic of capacitive coupling plasma reactor type, the LC series resonant inverter had been applied to take advantages of this topology with the implementation of SiC MOSFET power modules as switching power devices. Designation of gate driver for SiC MOSFET had been introduced by this paper. The 5kVp, 5kW power supply had also been verified by experimental results.

• Journal of IKEEE
• /
• v.25 no.1
• /
• pp.15-24
• /
• 2021

In this paper, 1700 V EPDT (Extended P+ shielding floating gate Double Trench) MOSFET structure, which has a smaller switching time and loss than CDT (Conventional Double Trench) MOSFET, is proposed. The proposed EPDT MOSFET structure extended the P+ shielding area of the source trench in the CDT MOSFET structure and divided the gate into N+ and floating P- polysilicon gate. By comparing the two structures through Sentaurus TCAD simulation, the on-resistance was almost unchanged, but Crss (Gate-Drain Capacitance) decreased by 32.54 % and 65.5 %, when 0 V and 7 V was applied to the gate respectively. Therefore, the switching time and loss were reduced by 45 %, 32.6 % respectively, which shows that switching performance was greatly improved.

• Proceedings of the KIPE Conference
• /
• 2020.08a
• /
• pp.407-408
• /
• 2020

본 논문은 SiC-MOSFET 기반 전기차용 인버터의 DC-Link 캐패시터 전기용량을 선정하는 방법에 대해 연구하였다. 인버터 시스템에 주로 사용되는 DC-Link 캐패시터는 안정적인 전원 및 고주파 전류 공급 등의 중요한 역할을 한다. 그러나 인버터가 고용량일수록 캐패시터 사이즈가 커지고 무게가 늘어나는 문제가 발생한다. 따라서, 차세대 전력 반도체 소자로 각광 받는 SiC-MOSFET의 높은 동작 주파수의 특성을 활용하여 캐패시터 소형화를 실현시켰다. 또한, PSIM 시뮬레이션을 통해 제안하는 연구의 타당성을 검증하고 Si-IGBT 인버터와 비교하여 그 효과를 입증하였다.

• Journal of IKEEE
• /
• v.28 no.1
• /
• pp.46-52
• /
• 2024

In this study, we investigated the electrical characteristics of SiC MOSFETs by depositing Si and oxidizing it to form the gate oxide layer. A thin Si layer was deposited approximately 20 nm thick on top of the SiC epi layer, followed by oxidation to form a gate oxide layer of around 55 nm. We compared devices with gate oxide layers produced by oxidizing SiC in terms of interface trap density, on-resistance, and field-effect mobility. The fabricated devices achieved improved interface trap density (~8.18 × 10¹¹ eV^-1cm^-2), field-effect mobility (27.7 cm²/V·s), and on-resistance (12.9 mΩ·cm²).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.36 no.4
• /
• pp.385-390
• /
• 2023

In this paper, the 1,700 V level SiC-based power MOSFET device widely used in electric vehicles and new energy industries was designed, that is, a single trench gate power MOSFET structure and a double trench gate power MOSFET structure were proposed to analyze electrical characteristics while changing the design and process parameters. As a result of comparing and analyzing the two structures, it can be seen that the double trench gate structure shows quite excellent characteristics according to the concentration of the drift layer, and the breakdown voltage characteristics according to the depth of the drift layer also show excellent characteristics of 200 V or more. Among them, the trench gate power MOSFET device can be applied not only to the 1,700 V class but also to a voltage range above it, and it is believed that it can replace all Si devices currently applied to electric vehicles and new energy industries.

• Proceedings of the KIPE Conference
• /
• 2019.07a
• /
• pp.275-276
• /
• 2019

본 논문에서는 SiC MOSFET을 적용한 10kW급 배터리 충전장치용 3상 PWM 정류기를 개발한다. 개발한 정류기는 3상 Bridge에 IGBT를 대체할 수 있는 WBG 전력반도체 SiC MOSFET을 적용하여 스위칭 주파수 향상 및 고전력밀도를 달성하였다. 개발한 10kW급 3상 PWM 정류기의 효율 및 THD 성능을 실험을 통해 검증한다.

• Journal of Power Electronics
• /
• v.19 no.2
• /
• pp.591-601
• /
• 2019

With the development of renewable energy, grid-connected inverter technology has become an important research area. When compared with traditional silicon IGBT power devices, the silicon carbide (SiC) MOSFET shows obvious advantages in terms of its high-power density, low power loss and high-efficiency power supply system. It is suggested that this technology is highly suitable for three-phase AC motors, renewable energy vehicles, aerospace and military power supplies, etc. This paper focuses on the SiC MOSFET behaviors that concern the parasitic component influence throughout the whole working process, which is based on a three-phase grid-connected inverter. A high-speed model of power switch devices is built and theoretically analyzed. Then the power loss is determined through experimental validation.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.25 no.3
• /
• pp.204-212
• /
• 2020

In this study, device suitability analysis is performed by comparing the performance of SiC MOSFET and GaN Transistor, which are WBG power semiconductor devices in the induction heating (IH) system. WBG devices have the advantages of low conduction resistance, switching losses, and fast switching due to their excellent physical properties, which can achieve high output power and efficiency in IH systems. In this study, SiC and GaN are applied to a general half-bridge series resonant converter topology to compare the conduction loss, switching loss, reverse conduction loss, and thermal performance of the device in consideration of device characteristics and circuit conditions. On this basis, device suitability in the IH system is analyzed. A half-bridge series resonant converter prototype using the SiC and GaN of a 650-V rating is constructed to verify device suitability through performance comparison and verified through an experimental comparison of power loss and thermal performance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.16 no.7
• /
• pp.584-592
• /
• 2003

6H-SiC MOSFETs and digital ICs have been fabricated and characterized. PMOS devices are fabricated on an n-type epilayer while the NMOS devices are fabricated on implanted p-wells. NMOS and PMOS devices use a thermally grown gate oxide. SiC MOSFETs are fabricated using different impurity activation methods such as high temperature and newly proposed laser annealing methods. Several digital circuits, such as resistive road NMOS inverters, CMOS inverters, resistive road NMOS NANDs and NORs are fabricated and characterized.