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61.
[110]-surface strained-SOI CMOS devices 总被引:1,自引:0,他引:1
Mizuno T. Sugiyama N. Tezuka T. Moriyama Y. Nakaharai S. Takagi S. 《Electron Devices, IEEE Transactions on》2005,52(3):367-374
We have newly developed [110]-surface strained-silicon-on-insulator (SOI) n- and p-MOSFETs on [110]-surface relaxed-SiGe-on-insulator substrates with the Ge content of 25%, fabricated by applying the Ge condensation technique to SiGe layers grown on [110]-surface SOI wafers. We have demonstrated that the electron and the hole mobility enhancement of [110]-surface strained-SOI devices amounts to 23% and 50%, respectively, against the mobilities of [110]-surface unstrained MOSFETs. As a result, the electron and the hole mobility ratios of [110]-surface strained-SOI MOSFETs to the universal mobility of (100)-surface bulk-MOSFETs increase up to 81% and 203%, respectively. Therefore, the current drive imbalance between n- and p-MOS can be reduced. Moreover, both the electron and the hole mobilities of the [110]-surface strained-SOIs strongly depend on the drain current flow direction, which is qualitatively explained by the anisotropic effective mass characteristics of the carriers on a [110]-surface Si. As a result, the [110]-surface strained-SOI technology with optimization of the current flow directions of n- and p-MOS is promising for realizing higher speed scaled CMOS. 相似文献
62.
Tetsuya Suemitsu Yoshino K. Fukai Hiroki Sugiyama Kazuo Watanabe Haruki Yokoyama 《Microelectronics Reliability》2002,42(1):47-52
The reliability of InP-based HEMTs is studied, focussing on how it is affected by the doped layer material and gate recess structure. Bias-and-temperature stress tests reveal that fluorine-induced donor passivation in the recess region, formed adjacent to the gate electrode, causes the source resistance (Rs) to increase at large drain bias voltages. The increase in Rs can be prevented by using InP or InAlP as the carrier supply layer material instead of InAlAs. On the other hand, the increase in the drain resistance (Rd) does not depend on the material of the carrier supply layer, which suggests that a mechanism different from that in the case of Rs should be considered. It is also found that a deep gate recess suppresses the increase in Rd after long-term stressing. 相似文献
63.
Wong E. H. Koh S. W. Lee K. H. Lim K.-M. Lim T. B. Mai Y.-W. 《Advanced Packaging, IEEE Transactions on》2006,29(4):751-759
Two advanced techniques have been developed for modeling vapor pressure within the plastic IC packages during solder reflow. The first involves the extension of the "wetness" technique to delamination along multimaterial interface and during dynamic solder reflow. Despite its simplicity, this technique is capable of offering reliable and accurate prediction for packages with high flexural rigidity. For packages with low flexural rigidity, the new "decoupling" technique that integrates thermodynamics, moisture diffusion, and structural analysis into a unified procedure has been shown to be more useful. The rigorous technique has been validated on both leadframe-based as well as laminate-based packages. With high accuracy and computational efficiency, these dynamic modeling tools will be valuable for optimization of package construction, materials, and solder reflow profile against popcorn cracking for both SnPb and Pb-free solders 相似文献
64.
Energy Storage: Novel Polygonal Vanadium Oxide Nanoscrolls as Stable Cathode for Lithium Storage (Adv. Funct. Mater. 12/2015) 下载免费PDF全文
65.
The Internet is a set of interconnected domains in which different QoS technologies can be deployed. The dynamic provision of end-to-end QoS over heterogeneousip networks assumes the negotiation of mutually acceptablesla. This paper presents the concept of intra-, inter- and multiple-domain service level negotiation using thecops-sls protocol. The negotiation process gives different parties in the negotiation the ability to agree upon the service level that a data stream can obtain, along with the permissible pricing of the service. 相似文献
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68.
Computer recognition of unconstrained handwritten numerals 总被引:13,自引:0,他引:13
Suen C.Y. Nadal C. Legault R. Mai T.A. Lam L. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1992,80(7):1162-1180
Four independently, developed expert algorithms for recognizing unconstrained handwritten numerals are presented. All have high recognition rates. Different experimental approaches for incorporating these recognition methods into a more powerful system are also presented. The resulting multiple-expert system proves that the consensus of these methods tends to compensate for individual weaknesses, while preserving individual strengths. It is shown that it is possible to reduce the substitution rate to a desired level while maintaining a fairly high recognition rate in the classification of totally unconstrained handwritten ZIP code numerals. If reliability is of the utmost importance, substitutions can be avoided completely (reliability=100%) while retaining a recognition rate above 90%. Results are compared with those for some of the most effective numeral recognition systems found in the literature 相似文献
69.
Wei-Hsun Lin Chi-Che Tseng Kuang-Ping Chao Shu-Cheng Mai Shih-Yen Lin Meng-Chyi Wu 《Photonics Technology Letters, IEEE》2009,21(18):1332-1334
A ten-period InAs-GaAs quantum-dot infrared photodetector (QDIP) with 8-nm In0.15Ga0.85 As capping layer grown after quantum-dot (QD) deposition is investigated. With reduced InAs QD coverage down to 2.0 mono-layers, responses at 10.4 and 8.4 mum are observed for the device under positive and negative biases, respectively. The phenomenon is attributed to the large Stark effect resulted from the asymmetric band diagrams of the device under different voltage polarities. The demonstration of long-wavelength infrared detections with the simple structures of the InGaAs-capped QDIP is advantageous for the development of multicolor QDIP focal-plane arrays. 相似文献
70.
早始新世极热气候(IETM)事件严重影响了海洋和湖泊的水体性质和生物活动。依据钻井岩心、元素分析、有机碳同位素与有机碳含量等实验结果,研究了东营断陷湖盆早始新世时期的湖泊水体氧化还原变化和古生产力条件,发现湖盆早期出现了较强的还原性,之后逐步恢复其氧化性。极热气候事件引起的湖水氧化还原界面的波动变化改变了其氧化还原格局,造成氧化还原环境与湖水深度变化的“不协调性”。湖盆早期具有较高的生产力,随后迅速降低之后逐渐增高,生产力的最低时期与极热气候(IETM)事件发生时期比较一致。由此证实了湖泊的时空波动演化经历了古新世-始新世时期的极热气候(IETM)事件,该事件具有明显的沉积记录和生物地球化学响应,决定了原始湖盆的水体氧化还原性质和生命活动过程,改变了整个湖盆的氧化还原结构。极热气候引起的湖水缺氧咸化造成了湖泊生产力的短暂降低,而随着恢复期的增氧作用的加强,生产力得到了极大的恢复,尤其是沙河街组四段有机碳含量较高,具有较高的生产力,成为主要的生油层和致密油气产层。 相似文献