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991.
Saito M. Yoshitomi T. Hara H. Ono M. Akasaka Y. Nii H. Matsuda S. Momose H.S. Katsumata Y. Ushiku Y. Iwai H. 《Electron Devices, IEEE Transactions on》1993,40(12):2264-2272
A p-MOSFET structure with solid-phase diffused drain (SPDD) is proposed for future 0.1-μm and sub-0.1-μm devices. Highly doped ultrashallow p+ source and drain junctions have been obtained by solid-phase diffusion from a highly doped borosilicate glass (BSG) sidewall. The resulting shallow, high-concentration drain profile significantly improves short channel effects without increasing parasitic resistance. At the same time, an in situ highly-boron-doped LPCVD polysilicon gate is introduced to prevent the transconductance degradation which arises in ultrasmall p-MOSFETs with lower process temperature as a result of depletion formation in the p+-polysilicon gate. Excellent electrical characteristics and good hot-carrier reliability are achieved 相似文献
992.
Scaling theory for double-gate SOI MOSFET's 总被引:5,自引:0,他引:5
Suzuki K. Tanaka T. Tosaka Y. Horie H. Arimoto Y. 《Electron Devices, IEEE Transactions on》1993,40(12):2326-2329
A scaling theory for double-gate SOI MOSFETs, which gives guidance for device design (silicon thickness tsi; gate oxide thickness tox) that maintains a subthreshold factor for a given gate length is discussed. According to the theory, a device can be designed with a gate length of less than 0.1 μm while maintaining the ideal subthreshold factor. This is verified numerically with a two-dimensional device simulator 相似文献
993.
A vertical cavity surface emitting semiconductor laser is described which uses zinc diffusion and partial disordering of the epitaxial output mirror to provide waveguiding for lateral mode control. Mode suppression ratios against higher order transverse modes as high as 36 dB have been observed.<> 相似文献
994.
The authors report the development of a triple-channel HEMT with two undoped In/sub 0.53/Ga/sub 0.47/As layers and a spike-doped In/sub 0.52/Al/sub 0.48/As layer on InP, designed to have a strongly nonlinear transconductance. The effective electron velocity and the electron density in the InGaAs layers are higher than in the thick InAlAs layer resulting in a highly nonlinear transconductance device with the potential for improved performance in nonlinear microwave circuit applications, as compared with conventional MESFETs and HEMTs.<> 相似文献
995.
A 4*4 directional coupler switch matrix is developed which uses, for the first time, the quantum confined Stark effect of InGaAlAs/InAlAs multiquantum well structures. The rearrangeable nonblocking 4*4 network with six 2*2 switches is shown to be perfectly functional with switching voltages between 5 and 6 V and crosstalk below -17 dB in all the operation states.<> 相似文献
996.
Saitoh Y. Imai H. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1993,39(3):1014-1022
Codes are considered for correction and detection of unidirectional byte errors. A code construction based on the generalized concatenated code construction is proposed. This construction gives a large number of efficient codes. For example, from this construction, a 72-input-bit encoder of the triple unidirectional 8-bit-byte error-correcting and fourfold unidirectional 8-bit-byte error-detecting code with a length of 112 bits and rate 9/14 is obtained, whereas the ordinary triple 8-bit-byte error-correcting and fourfold 8-bit-byte error-detecting code of the same length has only 56 information bits and is of rate 1/2. The proposed construction is generalized to one that gives efficient short-length codes 相似文献
997.
Fukushima T. Matsumoto N. Nakayama H. Ikegami Y. Namegaya T. Kasukawa A. Shibata M. 《Photonics Technology Letters, IEEE》1993,5(9):963-965
Compressively strained 1.3-μm GaInAsP/InP multiple-quantum-well (MQW) ridge waveguide lasers were fabricated. Through optimizing the total well thickness, large bandwidth over 11 GHz was achieved, together with high quantum efficiency of about 0.48 W/A and high power output of 60 mW before rollover. The laser also showed less temperature sensitivity up to an elevated temperature of 85°C 相似文献
998.
Yamada M. Shimizu M. Ohishi Y. Temmyo J. Kanamori T. Sudo S. 《Photonics Technology Letters, IEEE》1993,5(9):1011-1013
A highly efficient Pr3+-doped fluoride fiber amplifier configuration with an optical circulator, in which the input signal light is amplified both forward and backward through a Pr3+-doped fluoride fiber, is investigated with a view to decreasing the drive current and improving the reliability of pump laser diodes (LD's). With this double-path configuration, a 25-dB signal gain is achieved at an LD drive current of 110 mA. This LD drive current is about half that needed for a conventional single-path configuration. It is also found that this double-path configuration provides a double-gain coefficient, a slightly low saturation power, and a slightly narrow spectral gain width 相似文献
999.
Nykolak G. Becker P.C. Shmulovich J. Wong Y.H. DiGiovanni D.J. Bruce A.J. 《Photonics Technology Letters, IEEE》1993,5(9):1014-1016
We report on the concentration- and pump-dependent lifetimes of the spontaneous emission in Er3+-doped fibers and Er3+ -doped waveguides. In addition, we measure the concentration dependence of the 550-nm fluorescence due to excited state absorption (ESA) 相似文献
1000.
Tohmori Y. Yoshikuni Y. Ishii H. Kano F. Tamamura T. Kondo Y. 《Electronics letters》1993,29(4):352-354
A broad range tuning of over 100 nm in tunable DBR lasers with superstructure grating (SSG) is reported. The SSG reflectors for 100 nm were designed and patterned by electron beam lithography. 1.55 mu m DBR lasers with SSG reflector operate in a single mode with a tuning range of 83 nm under CW conditions. With inclusion of the multimode operating region, the tuning range becomes as wide as 103 nm.<> 相似文献