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81.
A fully integrated CMOS limiting amplifier (LA) is presented. Its novel implementation of the offset compensation circuit completely removes bulky off-chip RC components. The LA is designed using a 0.18 mum CMOS technology and it obtains a 40 dB gain with a bandwidth of 1.8 GHz. The total power consumption is only 18.39 mW under a 1.8 V voltage supply. 相似文献
82.
Xin Peng Wang Eu-Jin Lim A. Hong Yu Yu Ming-Fu Li Chi Ren Wei-Yip Loh Chun Xiang Zhu Chin A. Trigg A.D. Yee-Chia Yeo Biesemans S. Guo-Qiang Lo Dim-Lee Kwong 《Electron Devices, IEEE Transactions on》2007,54(11):2871-2877
A lanthanum (La)-doped HfN is investigated as an n-type metal gate electrode on SiO2 with tunable work function. The variation of La concentration in (HfinfinLa1-x)Ny modulates the gate work function from 4.6 to 3.9 eV and remains stable after high-temperature annealing (900degC to 1000degC), which makes it suitable for n-channel MOSFET application. An ultrathin high-fc dielectric layer was formed at the metal/SiO2 interface due to the (HfinfinLa1-x)Ny and SiO2 interaction during annealing. This causes a slight reduction in the effective oxide thickness and improves the tunneling current of the gate dielectric by two to three orders. We also report the tunability of TaN with Al doping, which is suitable for a p-type metal gate work function. Based on our results, several dual-gate integration processes by incorporating lanthanum or aluminum into a refractory metal nitride for CMOS technology are proposed. 相似文献
83.
Kah-Wee Ang Chih-Hang Tung Balasubramanian N. Samudra G.S. Yee-Chia Yeo 《Electron Device Letters, IEEE》2007,28(7):609-612
We report the demonstration of 55 nm gate length strained n-channel field-effect transistors (n-FETs) having an embedded Si1-xGex structure that is beneath the Si channel region and which acts as a strain-transfer structure (STS). The Si1-xGex STS has lattice interactions with both the silicon source and drain regions and with the overlying Si channel region. This effectively results in a transfer of lateral tensile strain to the Si channel region for electron mobility enhancement. The mechanism of strain transfer is explained. Significant drive current Ion enhancement of 18% at a fixed off-state leakage Ioff of 100 nA/mum is achieved, which is attributed to the strain-induced mobility enhancement. Furthermore, continuous downsizing of transistors leads to higher Ion enhancement in the strained n-FETs, which is consistent with the increasing transconductance Gm improvement when the gate length is reduced. 相似文献
84.
Tantra J.W. Teck Meng Lim Bu-Sung Lee Chai Kiat Yeo 《Communications Letters, IEEE》2007,11(8):659-661
In this letter, we evaluate the effectiveness of a multi-stage contention scheme for wireless local area networks (WLANs) medium access control (MAC). Multi-stage contention schemes basically divide the stations into smaller groups to resolve the contention more efficiently. Previous researchers have proposed virtual grouping schemes for WLANs MAC. Here we quantitatively analyze what can be achieved with a simple grouping scheme, i.e. through multi-stage contention. Our analysis shows that the multi-stage scheme is efficient in resolving contention, making it a good alternative to the commonly used exponential backoff mechanism. 相似文献
85.
Kenry Joo Chuan Yeo Jiahao Yu Menglin Shang Kian Ping Loh Chwee Teck Lim 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(12):1593-1604
A novel graphene oxide (GO) nanosuspension liquid‐based microfluidic tactile sensor is developed. It comprises a UV ozone‐bonded Ecoflex–polydimethylsiloxane microfluidic assembly filled with GO nanosuspension, which serves as the working fluid of the tactile sensor. This device is highly flexible and able to withstand numerous modes of deformation as well as distinguish various user‐applied mechanical forces it is subjected to, including pressing, stretching, and bending. This tactile sensor is also highly deformable and wearable, and capable of recognizing and differentiating distinct hand muscle‐induced motions, such as finger flexing and fist clenching. Moreover, subtle differences in the handgrip strength derived from the first clenching gesture can be identified based on the electrical response of our device. This work highlights the potential application of the GO nanosuspension liquid‐based flexible microfluidic tactile sensing platform as a wearable diagnostic and prognostic device for real‐time health monitoring. Also importantly, this work can further facilitate the exploration and potential realization of a functional liquid‐state device technology with superior mechanical flexibility and conformability. 相似文献
86.
With the advent of the ubiquitous era, multimedia emotion/mood could be used as an important clue in multimedia understanding, retrieval, recommendation, and some other multimedia applications. Many issues for multimedia emotion recognition have been addressed by different disciplines such as physiology, psychology, cognitive science, and musicology. Recently, many researchers have tried to uncover the relationship between multimedia contents such as image or music and emotion in many applications. In this paper, we introduce the existing emotion models and acoustic features. We also present a comparison of different emotion/mood recognition methods. 相似文献
87.
A cross-layer framework for privacy enhancement in RFID systems 总被引:1,自引:0,他引:1
In this paper, we introduce a cross-layer framework for enhancing privacy in RFID systems. The framework relies on mechanisms in the physical (PHY) layer, as well as the medium access control (MAC) layer, to provide flexible protection over the unique identifiers of low-cost RFID tags. Such a framework prevents adversaries and malicious parties from tracking RFID tags through the monitoring of their unique identifiers. More specifically, our framework relies on masking of the identifier at the PHY layer, whereby bit-collisions are induced between the backscattered tag identifier and a protective mask, such that a legitimate reader can be allowed to recover the tag identifier but an illegitimate party would not be able to do so. To strengthen the level of protection provided by the bit-collision masking method, we present the randomized bit encoding scheme that is used in our framework. In addition, we also incorporate mechanisms in the MAC layer, and make use of cross-layer interactions between the MAC and the PHY layers to provide flexible privacy protection. This allows tags that do not require privacy protection to be read conveniently while allowing tags that need to be protected to stay protected. 相似文献
88.
Wen-Yan Yin Le-Wei Li Tat-Soon Yeo Mook-Seng Leong 《Electromagnetic Compatibility, IEEE Transactions on》2000,42(4):330-338
A generalized mathematical procedure is developed for investigating a TEz-polarized plane wave penetration through two-dimensional (2-D) multilayered cylindrical cavity-backed apertures. The mathematical treatment is based on the direct integral equation technique combined with the Galerkin's procedure. Both the near- and far-zone field solutions to such a multiple coupling system are obtained in an analytical form. By taking the aperture edge effects into account, the magnetic currents on the surrounded multiple apertures are expanded in terms of a series of Chebyshev polynomials of the first kind. Furthermore, parametric studies are performed to show the variation of the penetrated near-zone magnetic field in various cylindrical cavity-backed apertures with the aperture number and geometrical sizes 相似文献
89.
Polishchuk I. Yee-Chia Yeo Qiang Lu Tsu-Jae King Chenming Hu 《Device and Materials Reliability, IEEE Transactions on》2001,1(3):158-162
The degradation of 100-nm effective channel length pMOS transistors with 14 Å equivalent oxide thickness Jet Vapor Deposition (JVD) Si3N4 gate dielectric under hot-carrier stress is studied. Interface-state generation is identified as the dominant degradation mechanism. Hot-carrier-induced gate leakage may become a new reliability concern. Hot-carrier reliability of 14 Å Si3N4 transistors is compared to reliability of 16 Å SiO2 transistors 相似文献
90.
Joo-Hyoung Park Sang Jun Park Hee Ah Ahn In-Sik Nam Gwon Koo Yeo Jeong Ki Kil Young Kee Youn 《Microporous and mesoporous materials》2009,117(1-2):178-184
Libraries consisting of more than 100 zeolite samples were prepared and examined for developing a promising HC trap catalyst. Parallel adsorptions of toluene onto the catalyst samples were conducted over a 10 × 10 array reactor under dry and wet conditions with or without a heating process three knowledge-based conditions for developing an automotive catalyst during the cold-start period. FAU and BEA type zeolites revealed a high performance of toluene adsorption under the dry condition. However, FAU type zeolite significantly decreased the amount of toluene adsorbed in the presence of water in the feed gas stream, mainly due to the hydrophobicity of the catalyst surface. Over Beta type zeolites, the toluene adsorbed was found to be considerably preserved, even after forced desorption temperature-ramping to the warm-up condition of an automotive engine. Li, K, or Ag ion-exchanged Beta zeolites seem to be particularly promising as an HC trap catalyst. 相似文献