A technical paper titled “Substrate Embedded Power Electronics Packaging for Silicon Carbide MOSFETs” was published by researchers at University of Cambridge, University of Warwick, Chongqing University, and SpaceX.

Abstract:

“This paper proposes a new power electronic packaging for discrete dies, namely Standard Cell which consists of a step-etched active metal brazed (AMB) substrate and a flexible printed circuit board (flex-PCB). The standard cell exhibits high thermal conductivity, complete electrical insulation, and low stray inductance, thereby enhancing the performance of SiC MOSFET devices. The standard cell has a stray power loop inductance of less than 1 nH and a gate loop inductance of less than 1.5 nH . The standard cell has a flat body with surface-mounting electrical connections on one side and direct thermal connections on the other. The use of flex-PCB die interconnection enables maximum utilization of source pads while providing a flexible gate-source connection and the converter PCB. This paper presents the design concept of the standard cell and experimentally validates its effectiveness in a converter system.”

Find the technical paper here. Published May 2024.

A. Janabi et al., “Substrate Embedded Power Electronics Packaging for Silicon Carbide MOSFETs,” in IEEE Transactions on Power Electronics, doi: 10.1109/TPEL.2024.3396779.

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The post Power Electronic Packaging for Discrete Dies appeared first on Semiconductor Engineering.

A new technical paper titled “Vertical-Stack Nanowire Structure of MOS Inverter and TFET Inverter in Low-temperature Application” was published by researchers at National Tsing Hua University and National United University in Taiwan.

Abstract
“Tunneling field effect transistors (TFET) have emerged as promising candidates for integrated circuits beyond conventional metal oxide semiconductor field effect transistors (MOSFET) and could overcome the physical limit, which results in the subthreshold swing (SS) < 60mV/dec at room temperature. In this study, we compare the complementary TFET (CTFET) with complementary metal oxide semiconductor (CMOS) at low temperatures (70K) by using the Gate-All-Around (GAA) architecture. The experiment result clearly shows that the CTEFT inverter has better characteristics than the CMOS inverter in various temperatures. While operating at a fixed temperature, the CMOS inverter performs an excellent on/off ratio and SS, etc. However, when a CMOS inverter operates at varying temperatures, CMOS performs worse than CTFET. This is attributed to the influence of lattice scattering, leading to the instability of CMOS characteristics. Therefore, the CTFET inverter is suitable for operation in environments with varying temperatures, exhibiting high stability, which can be applied in space technology. The simulation tool TCAD has been used to investigate the characteristics of CMOS and CTFET at low temperatures.”

Find the technical paper here. Published June 2024.

C. -C. Tien and Y. -H. Lin, “Vertical-Stack Nanowire Structure of MOS Inverter and TFET Inverter in Low-temperature Application,” in IEEE Access, doi: 10.1109/ACCESS.2024.3410677.

The post Device Characteristics of GAA-Structured CMOS and CTFET Under Varying Temperatures appeared first on Semiconductor Engineering.

A technical paper titled “Low Power and Temperature-Resilient Compute-In-Memory Based on Subthreshold-FeFET” was published by researchers at Zhejiang University, University of Notre Dame, Technical University of Munich, Munich Institute of Robotics and Machine Intelligence, and the Laboratory of Collaborative Sensing and Autonomous Unmanned Systems of Zhejiang Province.

Abstract:

“Compute-in-memory (CiM) is a promising solution for addressing the challenges of artificial intelligence (AI) and the Internet of Things (IoT) hardware such as ‘memory wall’ issue. Specifically, CiM employing nonvolatile memory (NVM) devices in a crossbar structure can efficiently accelerate multiply-accumulation (MAC) computation, a crucial operator in neural networks among various AI models. Low power CiM designs are thus highly desired for further energy efficiency optimization on AI models. Ferroelectric FET (FeFET), an emerging device, is attractive for building ultra-low power CiM array due to CMOS compatibility, high ION /IOF  ratio, etc. Recent studies have explored FeFET based CiM designs that achieve low power consumption. Nevertheless, subthreshold-operated FeFETs, where the operating voltages are scaled down to the subthreshold region to reduce array power consumption, are particularly vulnerable to temperature drift, leading to accuracy degradation. To address this challenge, we propose a temperature-resilient 2T-1FeFET CiM design that performs MAC operations reliably at subthreahold region from 0 to 85 Celsius, while consuming ultra-low power. Benchmarked against the VGG neural network architecture running the CIFAR-10 dataset, the proposed 2T-1FeFET CiM design achieves 89.45% CIFAR-10 test accuracy. Compared to previous FeFET based CiM designs, it exhibits immunity to temperature drift at an 8-bit wordlength scale, and achieves better energy efficiency with 2866 TOPS/W.”

Find the technical paper here. Published January 2024 (preprint).

Zhou, Yifei, Xuchu Huang, Jianyi Yang, Kai Ni, Hussam Amrouch, Cheng Zhuo, and Xunxhao Yin. “Low Power and Temperature-Resilient Compute-In-Memory Based on Subthreshold-FeFET.” arXiv preprint arXiv:2312.17442 (2023).

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The post Ultra-Low Power CiM Design For Practical Edge Scenarios appeared first on Semiconductor Engineering.