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The continued miniaturization of chips demands highly thermally conductive materials and effective thermal management strategies. Particularly, the high‐field transport of the devices built with 2D materials is limited by self‐heating. Here a systematic control of heat flow in single‐side fluorinated graphene (FG) with varying degrees of fluorination is reported, revealing a superior room‐temperature thermal conductivity as high as 128 W m−1 K−1. Monolayer graphene/FG lateral heterostructures with seamless junctions are approached for device fabrication. Efficient in‐plane heat removal paths from graphene channel to side FG are created, contributing significant reduction of the channel peak temperature and improvement in the current‐carrying capability and power density. Molecular dynamics simulations indicate that the interfacial thermal conductance of the heterostructure is facilitated by the high degree of overlap in the phonon vibrational spectra. The findings offer novel design insights for efficient heat dissipation in micro‐ and nanoelectronic devices. [ABSTRACT FROM AUTHOR]

A new kind of perylene‐based 2D covalent organic framework (COF) is designed and synthesized based on the C2 + C2 topological diagram. The perylene‐based COF is constructed via the condensation reaction using 2,5,8,11‐tetrakis((4‐formylphenyl) perylene (TFPPer) and 2,5,8,11‐tetrakis(4‐aminophenyl) perylene (TAPPer) as building blocks. The resulting TFPPer‐TAPPer‐COF features high crystallinity, excellent stability, intrinsic porosity, and an electron‐rich skeleton. Significantly, the electrical performance of the COF can be enhanced through the encapsulation of fullerene (C60) into the 1D channels via donor–acceptor interaction. Compared to the pristine COF, the electrical conductivity of C60@TFPPer‐TAPPer‐COF can be greatly increased from 8.98 × 10−8 to 1.59 × 10−5 S cm−1, meanwhile the carrier mobility rises from 1.04 × 10−3 to 4.23 × 10−2 cm2 V−1 s−1. The improvement in electrical performance stems from the strong donor–acceptor interaction between perylene and C60. These results provide insights into the rational construction of conductive COFs through donor–acceptor interaction and demonstrate their great potential in related application fields. [ABSTRACT FROM AUTHOR]

Multichip silicon carbide (SiC) power modules with Kelvin-source connections are commonly used in applications requiring large capacity. As a result of the parasitic effect induced by the interconnections in module packaging, the dynamic current mismatch among paralleled dies limits the available capacity of power modules. This article presents a general analysis on the mechanism of layout-dominated dynamic current balancing in multichip SiC power modules, utilizing a coupled parasitic network model. Focusing on the interrelation of parasitic parameters in the power module, a coupled parasitic network model is developed specially for switching transients, and the dynamic current balancing equations are derived. For the multichip power modules with two different layouts, the parasitic parameters pertaining to the proposed model are extracted by the finite-element analysis (FEA). The acquired parasitic parameters considering magnetic coupling are utilized to calculate and verify the dynamic current balancing equations. Moreover, based on these parasitic parameters, the electromagnetic coupling simulation is performed to evaluate the dynamic current sharing. Furthermore, for the validation of the proposed model and equations, experiments are conducted with the fabricated power module prototypes. [ABSTRACT FROM AUTHOR]

This article presents quick analytical prediction methods of switching loss, turn-on/off overvoltage, di/dt, and dv/dt for SiC metal–oxide–semiconductor field-effect transistor based on device datasheet. First, the switching process is analyzed and the simplification principles are discussed based on charge conservation and flux conservation. Second, the analytical equations of switching loss, turn-on/off overvoltage, di/dt, and dv/dt are derived. Third, experimental results under different operating conditions are presented to validate the proposed methods. It is found that the average prediction error is 10.11%. Finally, relationships between switching performance and different parameters, such as parasitic capacitance, parasitic inductance, dc-voltage, and load current, are analyzed and summarized based on the proposed prediction methods. [ABSTRACT FROM AUTHOR]

Inorganic metal halide (IMH) perovskites have recently emerged as highly promising optoelectronic materials due to their excellent material properties, including tunable direct bandgap, long carrier diffusion length, high carrier mobility and outstanding environmental stabilities. However, the performance of photodetectors fabricated from IMH perovskites so far is limited as compared to their counterparts based on organic–inorganic hybrid perovskites. In this work, we demonstrate a high performance ultraviolet–visible (UV–Vis) dual-band photodetector based on a Cs2SnI6/ZnO heterojunction structure. By adjusting the polarity of the applied bias voltage, the photodetector can switch between two operation modes: (1) UV–Vis dual-band detection mode and (2) visible-blind UV detection mode. High detectivity in both the UV (1.39 × 1012 Jones) and visible (5.88 × 1011 Jones) regions is achieved. In addition, this photodetector demonstrated a fast response speed with a rise and fall time on the order of milliseconds and a large linear dynamic range of 119 dB. The excellent performance of this photodetector originates from efficient charge separation at the heterojunction interfaces, which will be discussed in detail in terms of the energy band diagrams and carrier dynamics of the device. Our study demonstrates the great application potential of inorganic vacancy-ordered perovskites in high-performance heterojunction photodetectors. [ABSTRACT FROM AUTHOR]