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Since the invention of transistors and integrated circuits, the development of semiconductor processes has advanced rapidly. Current microchips contain hundreds of millions of transistors. The remarkable development of semiconductors thus far has also led to difficulties in designing tightly packed lithography patterns without unwanted defects called hotspots in the manufacturing process. Therefore, research areas focusing on these problems have received much attention. In particular, predicting hotspots during the design stage is essential for high productivity in the semiconductor industry. In this study, we developed a deep learning-based SEM image generation model to predict hotspots from layout patterns at the design stage. Our model combines a segmentation network and an image-to-image translation network based on a conditional generative adversarial network in parallel. Our proposed model can predict and display potential hotspots in scanning electron microscopy images generated from given layouts. Additionally, the model leverages prior knowledge of the optical diameter to predict patterns that are prone to hotspots. Our model shows improved performance over baseline models when evaluated on real-world industrial data. [ABSTRACT FROM AUTHOR]

In this article, a modular output series-parallel series resonant converter (SRC) differential buck converter is analyzed for high-power, ultra-wide-voltage applications such as battery formation systems and bench-type power supplies where a zero voltage discharging function is required. An independent control method in one module is proposed to increase the efficiency of the converter compared to the conventional complementary control method. In the modular output-series connection, higher efficiency can be achieved by shedding needless modules in the low voltage range. Module shedding and activating techniques are proposed to eliminate current and voltage transients during a mode change under any load condition without the use of additional bypass switches. In addition, when a fault occurs in one module, its effect on the other module is analyzed. A practical solution involving turn-off processes for fail-safe operation is proposed, which reduces current stress and voltage spikes on devices and effect among modules without depending on the external signal from the central controller and the communication delay. A prototype of a modular series-parallel SRC- differential buck converter is implemented to verify the proposed concept. [ABSTRACT FROM AUTHOR]

Detecting defects in the inspection stage of semiconductor manufacturing process is a crucial task to improve yield and productivity as well as wafer quality. Recent Advances in semiconductor process technology have greatly increased the transistor density. As a result, an increasingly high number of defects inevitably emerge and we need a more accurate and efficient detection method to manage them. In this paper, we propose a deep-learning-based defect detection model to expedite the process. It adopts an adversarial network architecture of conditional GAN. The discriminator of an adversarial network architecture helps the detection model learn to detect and classify defects accurately. The high performance is achieved by using Focal Loss, PixelGAN and multi-scale level features, which is shown to be better than the baseline model, CenterNet, when tested for a real industrial dataset. [ABSTRACT FROM AUTHOR]

This article introduces an augmented adaptive unscented Kalman filter (KF). The proposed novel technique is suitable to simultaneously estimate both the diagonal process noise covariance matrix and the unknown inputs, thus combining previously reported KF estimators for unknown inputs (dual or joint KF) and for covariance matrices (adaptive KF). A selective scaling method is also introduced to improve the convergence property of the suggested KF. The development of the novel KF is also motivated by a specific estimation problem related to crane systems. Cranes represent a special class of weight handling equipment as they are underactuated and described by nonlinear dynamics such that the load present oscillatory behavior. In addition to the increasing need for their automation in various industrial fields, these features also make them a benchmark system in control engineering with numerous control laws reported in the literature for sway elimination and trajectory tracking. A common issue to realize most of the advanced control laws on real, eventually industrial size cranes is the necessity to know the sway angle and frictions on the configuration variables. It is shown in simulation and also with real experiments on a reduced size overhead crane system that the suggested KF is suitable to estimate both the sway angles and the frictions. [ABSTRACT FROM AUTHOR]

This letter presents a novel reconfigurable microstrip antenna with a frequency of 28 GHz and an embedded liquid crystal (LC). First, a novel fabrication process that employs a heat press machine is developed. This allows for the successful creation of thin substrates with thicknesses ranging between 0.13 and 0.25 mm. It is validated that the proposed stacked topology achieves a wide tunable range of resonant frequency. In addition, a simple bias configuration is achieved by connecting the bias position to the middle of the patch, where radio frequency (RF) potential is zero. The proposed antenna adopts a three-layer stacked printed circuit board (PCB) structure to render a cavity in which the LC is injected. The bottom patch of the top substrate is designed to contact the LC, and thus, it simultaneously functions as a dc bias electrode and a radiating element. In addition, unlike conventional stacked patch antennas, the additional patch on the top of the PCB structure is tuned to enhance gain. Compared with the simulated performance of a prior LC-based antenna, the tunable range of the resonant frequency of the proposed antenna is improved by more than three times at a center frequency of 28 GHz and the peak radiation efficiency is improved by up to 17%. Furthermore, the area (252 mm2) of the proposed LC-based antenna is 40% of the area of the prior LC-based antenna (625 mm2). [ABSTRACT FROM AUTHOR]

The intercarrier interference (ICI) resulting from the loss of orthogonality caused by the time-varying property of the propagation channels degrades the data detection performance of orthogonal frequency-division multiplexing (OFDM)-based wireless communication systems. Further, the severity of the problem increases when the mobile speed is relatively higher than the number of subcarriers. In this paper, a time-varying filtering method is proposed that reduces ICI by obtaining an approximation of linear system solutions such as zero-forcing (ZF) and minimum mean square error (MMSE). The update rates of the time-varying filter coefficients, which are actually the minimum phase versions of the channel impulse responses, are also minimized to reduce the computational complexity. The simulation results show that the proposed method with lower complexity effectively reduces ICI such that practical application is deemed feasible for OFDM systems with a large number of subcarriers. [ABSTRACT FROM PUBLISHER]

With the increasing amount of new motion-sensing hardware, improving the usability of gesture interfaces is becoming more important. However, people don't accept gesture interfaces as comfortably as traditional interfaces because they lack the tactile or haptic feedback of traditional input methods, such as mice or keyboards. However, having tactile feedback in gesture interfaces isn't possible unless users are wearing a device with actuators. Therefore, auditory feedback is an appropriate and unique alternative for assisting visual feedback in gesture interfaces. The authors propose various types of novel auditory feedback methods and explore their effects as secondary feedback on complementing visual feedback. They performed a user study for a menu selection task, and experimental results show that the proposed auditory feedback is significantly more efficient and effective than visual-only feedback or conventional auditory feedback in terms of time and accuracy. [ABSTRACT FROM PUBLISHER]

Content-centric networking (CCN) is considered promising for the efficient support of ever-increasing streaming multimedia services. Inter-chunk popularity-based caching is one of the key requirements in CCN multimedia services because some chunks of a content file tend to be requested more frequently than others. For multimedia contents, forepart chunks often have higher popularity than others as users may interrupt and abort before finishing its service. This paper presents a novel cache replication scheme, which places more popular chunks ahead on the edge router, and establishes a cache pipelining on the relaying routers along the path to reduce user-perceived delay. Simulation results show that the proposed scheme incurs less delay and reduces the overall redundant network traffic while guaranteeing a higher cache hit ratio. [ABSTRACT FROM PUBLISHER]

Antennas implanted in a human body are largely applicable to hyperthermia and biotelemetry. To make practical use of antennas inside a human body, resonance characteristics of the implanted antennas and their radiation signature outside the body must be evaluated through numerical analysis and measurement setup. Most importantly, the antenna must be designed with an in-depth consideration given to its surrounding environment. In this paper, the spherical dyadic Green's function (DGF) expansions and finite-difference time-domain (FDTD) code are applied to analyze the electromagnetic characteristics of dipole antennas and low-profile patch antennas implanted in the human head and body. All studies to characterize and design the implanted antennas are performed at the biomedical frequency band of 402-405 MHz. By comparing the results from two numerical methodologies, the accuracy of the spherical DGF application for a dipole antenna at the center of the head is evaluated. We also consider how much impact a shoulder has on the performance of the dipole inside the head using FDTD. For the ease of the design of implanted low-pro- file antennas, simplified planar geometries based on a real human body are proposed. Two types of low-profile antennas, i.e., a spiral microstrip antenna and a planar inverted-F antenna, with superstrate dielectric layers are initially designed for medical devices implanted in the chest of the human body using FDTD simulations. The radiation performances of the designed low-profile antennas are estimated in terms of radiation patterns, radiation efficiency, and specific absorption rate. Maximum available power calculated to characterize the performance of a communication link between the designed antennas and an exterior antenna show how sensitive receivers are required to build a reliable telemetry link. [ABSTRACT FROM AUTHOR]