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In this article, the static, dynamic, and short-circuit properties of 1.2-kV commercial 4H-SiC planar and trench gate metal–oxide–semiconductor field-effect transistors (MOSFETs) are compared and analyzed in a wide temperature range from 90 to 493 K. The temperature-dependent specific ON-resistance (${R}_{\text {sp}- \mathrm{\scriptscriptstyle ON}}$) and threshold voltage (${V}_{\text {th}}$) are analyzed in relation to the density of the interface state. The turn-on rise and turn-off fall times (${T}_{r}$ and ${T}_{f}$) and the corresponding energy loss (${E}_{r}$ and ${E}_{f}$) are extracted from a double-pulse test from cryogenic to high temperature and analyzed. The short-circuit capability of the two structures is studied at low temperature for the first time. The comprehensive comparison and analysis of the planar and trench gate MOSFET versus temperature in this work show the importance to study applications with SiC MOSFETs in a wide temperature range, especially for the cryogenic temperatures. [ABSTRACT FROM AUTHOR]

Multimedia data with various modalities, such as image and text, are huge in quantity but have inconsistent distribution and representation. Many works have been done to break the boundary between image and text to measure their correlation. However, they focus on either the transformation to common subspace or the unidirectional generation from one to another individually, which cannot fully explore their interactions. It is noted that the bidirectional generation between image and text not only can provide complementary hints and mutually boost to learn cross-modal correlation but also cross-modal correlation learning can feed back to give comprehensive clues for promoting the cross-modal generation process. Therefore, we have the motivation that information transmission between image and text should be treated as a circular process, which aims to fully understand their latent correlation, and further realize cross-modal generation to produce both realistic images and text descriptions in a unified framework. In this paper, we propose the cross-modal circular correlation learning approach to perform both cross-modal correlation learning and generation simultaneously through an efficient circular learning training procedure. First, we propose the cross-modal circular learning model to perform an image-to-text caption and text-to-image synthesis circularly and learn common representation as a round-trip bridge, which can realize efficient interactions to fully exploit latent cross-modal correlations. Second, a unified bidirectional framework is proposed to conduct cross-modal mutual generation and is trained in an efficient circular process to enhance the generative ability of common representation, which can feed back circularly to further promote cross-modal correlation learning. In summary, we simultaneously perform cross-modal retrieval, image-to-text caption, and text-to-image synthesis in a unified framework with the circular learning process, which has high scalability and generality to realize universal cognition on the cross-modal data. We conduct extensive experiments to not only evaluate the correlation performance by cross-modal retrieval but also to show the generation effectiveness of both image caption and synthesis on the MS-COCO dataset. [ABSTRACT FROM AUTHOR]

In this paper, an improved 4H-SiC U-shaped trench-gate metal–oxide–semiconductor field-effect transistors (UMOSFETs) structure with low ON-resistance (${R}_{ \mathrm{\scriptscriptstyle ON}}$) and switching energy loss is proposed. The novel structure features an added n-type region, which reduces ON-resistance of the device significantly while maintaining the breakdown voltage (${V}_{\textsf {BR}}$). In addition, the gate of the improved structure is designed as a p-n junction to reduce the switching energy loss. Simulations by Sentaurus TCAD are carried out to reveal the working mechanism of this improved structure. For the static performance, the ON-resistance and the figure of merit (FOM $= {V}_{\textsf {BR}}^{\textsf {2}}/{R}_{ \mathrm{\scriptscriptstyle ON}}$) of the optimized structure are improved by 40% and 44%, respectively, as compared to a conventional trench MOSFET without the added n-type region and modified gate. For the dynamic performance, the turn-on time (${T}_{ \mathrm{\scriptscriptstyle ON}}$) and turn-off time (${T}_{ \mathrm{\scriptscriptstyle OFF}}$) of the proposed structure are both shorter than that of the conventional structure, bringing a 43% and 30% reduction in turn-on energy loss and total switching energy loss (${E}_{\mathbf {SW}}$). [ABSTRACT FROM AUTHOR]