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991.
Ying-Hung So Stark E. J. Yongfu Li Kisting S. Achen A. Baranek K. Scheck D. Hetzner J. Folkenroth J. J. Tpper M. Baumgartner T. 《Advanced Packaging, IEEE Transactions on》2006,29(4):741-750
A positive-tone and aqueous-base-developable benzocyclobutene (BCB)-based dielectric material curable in air is described in this paper. The prepolymer is made from divinylsiloxane bisbenzocyclobutene (DVS-bisBCB) and BCB-acrylic acid. The formulation contains antioxidants that allow the prepolymer to cure in air and a diazonaphthaquinone to make it photosensitive. Patterned films have high resolution, and via openings are scum-free without a descum operation. Whether cured in nitrogen or in air, the prepolymer produces a film with optical, electrical, thermal, and mechanical properties desirable for many microelectronic applications, such as packaging applications and as a planarization or insulation layer in display applications 相似文献
992.
993.
994.
深入研究了亚30nm CMOS关键工艺技术,特别是提出了一种新的低成本的提高空穴迁移率的技术--Ge预非晶化S/D延伸区诱生沟道应变技术,它使栅长90nm pMOS空穴有效迁移率在0.6MV/cm电场下提高32%.而且空穴有效迁移率的改善,随器件特征尺寸缩小而增强.利用零阶劳厄线衍射的大角度会聚束电子衍射分析表明,在沟道区相应的压应变为-3.6%.在集成技术优化的基础上,研制成功了高性能栅长22nm应变沟道CMOS器件及栅长27nm CMOS 32分频器电路(其中分别嵌入了57级/201级环形振荡器),EOT为1.2nm,具有Ni自对准硅化物. 相似文献
995.
996.
Efficient encoding of quasi-cyclic low-density parity-check codes 总被引:10,自引:0,他引:10
Zongwang Li Lei Chen Lingqi Zeng Lin S. Fong W.H. 《Communications, IEEE Transactions on》2006,54(1):71-81
Quasi-cyclic (QC) low-density parity-check (LDPC) codes form an important subclass of LDPC codes. These codes have encoding advantage over other types of LDPC codes. This paper addresses the issue of efficient encoding of QC-LDPC codes. Two methods are presented to find the generator matrices of QC-LDPC codes in systematic-circulant (SC) form from their parity-check matrices, given in circulant form. Based on the SC form of the generator matrix of a QC-LDPC code, various types of encoding circuits using simple shift registers are devised. It is shown that the encoding complexity of a QC-LDPC code is linearly proportional to the number of parity bits of the code for serial encoding, and to the length of the code for high-speed parallel encoding. 相似文献
997.
A 2 /spl mu/m InGaP/GaAs heterojunction bipolar transistor (HBT) matrix amplifier with a new gain cell achieving 17.2 dB gain and 41 GHz bandwidth is reported. Using the gain-bandwidth products per transistor f/sub t/ and f/sub max/ as the figures of merit for measuring the effectiveness of amplifier design, it achieves 4.72 and 4.43, respectively, demonstrating among the best-reported bipolar broadband amplifiers 相似文献
998.
M.H. Hu Hong Ky Nguyen Kechang Song Yabo Li N.J. Visovsky Xingsheng Liu N. Nishiyama S. Coleman L.C. Hughes Jr. J. Gollier W. Miller R. Bhat Chung-En Zah 《Photonics Technology Letters, IEEE》2006,18(4):616-618
We report on the static and dynamic performance of high-power and high-modulation-speed 1060-nm distributed Bragg reflector (DBR) lasers for green-light emission by second-harmonic generation. Single-wavelength power of 387 mW at 1060-nm wavelength and green power as high as 99.5 mW were achieved. A thermally induced wavelength tuning of 2.4 nm and a carrier-induced wavelength tuning of -0.85 nm were obtained by injecting current into the DBR section. Measured rise-fall times of 0.2 ns for direct intensity modulation and 0.6 ns for wavelength modulation make the lasers suitable for >50-MHz green-light modulation applications. 相似文献
999.
A novel frequency offset estimation method for OFDM systems with large estimation range 总被引:4,自引:0,他引:4
Chunlin Yan Shaoqian Li Youxi Tang Xiao Luo Jiayi Fang 《Broadcasting, IEEE Transactions on》2006,52(1):58-61
In this paper, we proposed a novel frequency synchronization method which has larger estimation range than conventional method proposed by Tufvesson. A two steps frequency offset estimation method is performed in the new method. In the first step the received signal is correlated with local training sequence to eliminate the influence of training sequence which makes the estimation range of frequency offset is independent of period of the repeated data in the training sequence. The received signal is correlated with its delay in the second step to obtain the fine estimation of frequency offset. Precise estimation can be achieved in the proposed method than Tufvesson's method. The period of the repeated data in the training sequence determines the estimation range of the frequency offset in the conventional method, while in the new method they are irrelevant. Tens of subcarriers spacing can be estimated by the new method. The new method can be used in other cases as long as a known sequence is transmitted, which will introduce valuable flexibility in training sequence design. The validity of the algorithm is verified in AWGN channel and multipath fading channel. 相似文献
1000.
为解决光学加工CCOS模型固有的缺陷,将实例推理CBR引入到光学加工中.给出了CBR中光学加工实例的具体表达形式,并对CBR系统中的关键技术一一匹配算法,即相似度的求解进行详细的说明,在此基础上,建立了CBR原型系统.实践证明,该系统运行良好. 相似文献