Fifteen periods of Si/Si0.7Ge0.3 multilayers (MLs) with various SiGe thicknesses are grown on a 200 mm Si substrate using reduced pressure chemical vapor deposition (RPCVD). Several methods were utilized to characterize and analyze the ML structures. The high resolution transmission electron microscopy (HRTEM) results show that the ML structure with 20 nm Si0.7Ge0.3 features the best crystal quality and no defects are observed. Stacked Si0.7Ge0.3 ML structures etched by three different methods were carried out and compared, and the results show that they have different selectivities and morphologies. In this work, the fabrication process influences on Si/SiGe MLs are studied and there are no significant effects on the Si layers, which are the channels in lateral gate all around field effect transistor (L-GAAFET) devices. For vertically-stacked dynamic random access memory (VS-DRAM), it is necessary to consider the dislocation caused by strain accumulation and stress release after the number of stacked layers exceeds the critical thickness. These results pave the way for the manufacture of high-performance multivertical-stacked Si nanowires, nanosheet L-GAAFETs, and DRAM devices.
The development of new n-type semiconductors is crucial for the further advancement of electronic and optoelectronic devices. Steamed buns, anciently known as "man tou", mainly made of wheat flour and are one of the staple foods for Chinese people. After being subjected to high-temperature treatment, the steamed buns transformed into carbonized steamed buns (CSB) with porous nanostructures, which exhibit a Hall mobility of up to 1.62 cm2/(V·s), far greater than C60(1.5×10−3~2.5×10−2 cm2/(V·s)), PCBM (2.0×10−7 cm2/(V·s)) and many polymer semiconductors (~10−6~10−2 cm2/(V·s)). A CSB-based bulk heterojunction memristor with a configuration of ITO/the CSB: PVK blends/Al is successfully fabricated. The device shows outstanding history dependent memristive switching performance, with 35 distinguishable conductance states, at a small sweep voltage range of ±1V. An achieved production yield reaches up to 89%. Upon being subjected to consecutive positive or negative voltage sweeps, the current flowing through the device can be modulated continuously. When the 15 consecutive pulse voltages (pulse amplitude: 0.1 V; pulse width:10 μs, pulse period: 20 μs) were applied to the device, the observed total power consumption was about 7.63 nJ, suggesting a potential in low-energy neuromorphic computing applications. As expected, both the CSB and PVK do not exhibit any memristive effect under the same experimental condition. Utilizing the characteristic that the device can linearly adjust the weights, a simple convolutional neural network for traffic sign recognition was successfully constructed. After 300 rounds of training, the achieved recognition accuracy rate reached 88.77%. This work not only provides a new approach for developing low-cost and readily available organic semiconductors with high Hall mobility, but also offers a new idea for the subsequent development of high-performance artificial synapses and optoelectronic devices using carbonized steamed buns.
This work presents a novel radio frequency (RF) narrowband Si micro-electro-mechanical systems (MEMS) filter based on capacitively transduced slotted width extensional mode (WEM) resonators. The flexibility of the plate leads to multiple modes near the target frequency. The high Q-factor resonators of around 100 000 enable narrow bandwidth filters with small size and simplified design. The 1-wavelength and 2-wavelength WEMs were first developed as a pair of coupled modes to form a passband. To reduce bandwidth, two plates are coupled with a λ-length coupling beam. The 79.69 MHz coupled plate filter (CPF) achieved a narrow bandwidth of 8.8 kHz, corresponding to a tiny 0.011%. The CPF exhibits an impressive 34.84 dB stopband rejection and 7.82 dB insertion loss with near-zero passband ripple. In summary, the RF MEMS filter presented in this work shows promising potential for application in RF transceiver front-ends.
Robotic computing systems play an important role in enabling intelligent robotic tasks through intelligent algorithms and supporting hardware. In recent years, the evolution of robotic algorithms indicates a roadmap from traditional robotics to hierarchical and end-to-end models. This algorithmic advancement poses a critical challenge in achieving balanced system-wide performance. Therefore, algorithm-hardware co-design has emerged as the primary methodology, which analyzes algorithm behaviors on hardware to identify common computational properties. These properties can motivate algorithm optimization to reduce computational complexity and hardware innovation from architecture to circuit for high performance and high energy efficiency. We then reviewed recent works on robotic and embodied AI algorithms and computing hardware to demonstrate this algorithm-hardware co-design methodology. In the end, we discuss future research opportunities by answering two questions: (1) how to adapt the computing platforms to the rapid evolution of embodied AI algorithms, and (2) how to transform the potential of emerging hardware innovations into end-to-end inference improvements.
Artificial intelligence (AI) processes data-centric applications with minimal effort. However, it poses new challenges to system design in terms of computational speed and energy efficiency. The traditional von Neumann architecture cannot meet the requirements of heavily data-centric applications due to the separation of computation and storage. The emergence of computing in-memory (CIM) is significant in circumventing the von Neumann bottleneck. A commercialized memory architecture, static random-access memory (SRAM), is fast and robust, consumes less power, and is compatible with state-of-the-art technology. This study investigates the research progress of SRAM-based CIM technology in three levels: circuit, function, and application. It also outlines the problems, challenges, and prospects of SRAM-based CIM macros.
The optical properties of polypyrrole (Ppy) thin films upon 2 MeV electron beam irradiation changes with different doses. The induced changes in the optical properties for Ppy thin films were studied in the visible range 300 to 800 nm at room temperature. The optical band gap of the pristine Ppy was found to be 2.19 eV and it decreases up to 1.97 eV for a 50 kGy dose of 2 MeV electron beam. The refractive index dispersion of the samples obeys the single oscillator model. The obtained results suggest that electron beam irradiation changes the optical parameters of Ppy thin films.
Electrohydrodynamic (EHD) inkjet printing has emerged as a powerful micro-/nanofabrication technique for high-resolution perovskite quantum dot (PeQD) color-conversion layers, offering precise control over pixel morphology, dimensions, and composition. This review systematically examines the mechanisms of cone-jet and electrostatic-attraction modes in EHD printing, highlighting recent advances in PeQD ink design, solvent and ligand engineering, and printing parameter optimization. Perovskite precursor and colloidal inks are discussed in detail, emphasizing strategies to enhance droplet ejection stability, suppress coffee-ring effects, and achieve uniform, high-luminescence pixels. Ligand exchange, dual-ligand passivation, and core−shell or polymer encapsulation are shown to effectively mitigate ion migration, surface defects, and environmental degradation, thereby improving photoluminescence efficiency and stability. Multi-channel and multi-nozzle EHD printing systems enable dynamic halide composition control and parallel RGB pixel deposition, facilitating ultrahigh-resolution patterning down to submicron feature sizes. Finally, the review highlights future directions, including synergistic PeQD material synthesis, advanced ink formulation, scalable high-throughput printing, and integration of PeQD color-conversion pixels into full-color micro-LED displays with minimal crosstalk and robust operational stability. These developments collectively demonstrate the immense potential of EHD inkjet printing for next-generation high-performance display technologies.
Silicon carbide (SiC), as a third-generation semiconductor material, possesses exceptional material properties that significantly enhance the performance of power devices. The SiC lateral double-diffused metal–oxide–semiconductor (LDMOS) power devices have undergone continuous optimization, resulting in an increase in breakdown voltage (BV) and ultra-low specific on-resistance (Ron,sp). This paper has summarized the structural optimizations and experimental progress of SiC LDMOS power devices, including the trench-gate technology, reduced surface field (RESURF) technology, doping technology, junction termination techniques and so on. The paper is aimed at enhancing the understanding of the operational mechanisms and providing guidelines for the further development of SiC LDMOS power devices.
