http://ieeexplore.ieee.org/iel5/5610941/5624686/05624745.pdf

Power electronics

A marigold-like SiC@MoS2 nanoflower with a unique Z-scheme structure efficiently achieves the overall conversion of gas phase CO2 with H2O (CO2 (g) + 2H2O (g) = CH4 + 2O2) without any sacrificial reagents under visible light (λ ≥ 420 nm) irradiation. The CH4 and O2 evolution are 323 and 621 μL·g-1·h-1, and stable throughout 5 cycle reactions of total 40 h. This work demonstrates a breakthrough in artificial photosynthesis with the Z-scheme 1D heterojunction constructed by combining 2D semiconductor and 3D semiconductor based on the transfer balance of photogenerated electron and hole.

Visible-Light Driven Overall Conversion of CO2 and H2O to CH4 and O2 on 3D-SiC@2D-MoS2 Heterostructure.

The need for power semiconductor devices with high-voltage, high- frequency, and high-temperature operation capability is growing, especially for advanced power conversion and military applications, and hence the size and weight of the power electronic system are reduced. Development of 15-kV SiC IGBTs and their impact on utility applications is discussed.

Smart grid technologies

Simple analytical approximation has been obtained to describe the temperature and concentration dependencies of the low-field mobility in gallium nitride (GaN) in wide temperature (50⩽ T ⩽1000 K) and concentration (10 14 ⩽ N ⩽10 19 cm −3 ) ranges. The dependence of the temperature T m at which the mobility μ is at a maximum on the doping level is also obtained. Results obtained can be directly used for computer simulation of GaN-based devices.

Carrier mobility model for GaN

This paper presents a comprehensive short-circuit ruggedness evaluation and numerical investigation of up-to-date commercial silicon carbide (SiC) MOSFETs. The short-circuit capability of three types of commercial 1200-V SiC MOSFETs is tested under various conditions, with case temperatures from 25 to 200 °C and dc bus voltages from 400 to 750 V. It is found that the commercial SiC MOSFETs can withstand short-circuit current for only several microseconds with a dc bus voltage of 750 V and case temperature of 200 °C. The experimental short-circuit behaviors are compared, and analyzed through numerical thermal dynamic simulation. Specifically, an electrothermal model is built to estimate the device internal temperature distribution, considering the temperature-dependent thermal properties of SiC material. Based on the temperature information, a leakage current model is derived to calculate the main leakage current components (i.e., thermal, diffusion, and avalanche generation currents). Numerical results show that the short-circuit failure mechanisms of SiC MOSFETs can be thermal generation current induced thermal runaway or high-temperature-related gate oxide damage.

Temperature-Dependent Short-Circuit Capability of Silicon Carbide Power MOSFETs

The impact of non-1D effects caused by the spread of the gate current in the base layer on the gate switch-on current in 4H-SiC thyristors is considered. It is shown that a new switching mechanism implemented in 4H-SiC thyristors results in the dependence of the gate switch-on current on the thyristor parameters, with this dependence being fundamentally different from that in conventional silicon thyristors.

Analysis of the Impact of Non-1D Effects on the Gate Switch-On Current in 4H-SiC Thyristors

It is shown that, in the base region of Schottky diodes, at current densities j higher than a certain value jst1, quasi-neutral drift-stimulated diffusion is implemented along with diffusion transport The effect of this newly discovered mode in the I–V characteristics of Schottky diodes at high current densities is investigated It is demonstrated that, when the ratio between the base width W and the ambipolar diffusion length L is higher than unity, a negative-differential-resistance portion appears in the I–V characteristics of Schottky diodes The results of the analytical study are checked and confirmed by numerical calculation

Tigran T. Mnatsakanov

Papers

Analysis of the Impact of Non-1D Effects on the Gate Switch-On Current in 4H-SiC Thyristors

High-Power Schottky Diodes with a Negative-Differential-Resistance Portion in the I – V Characteristic