We define the communication complexity of a perfect zero-knowledge interactive proof (ZKIP) as the expected number of bits communicated to achieve the given error probabilities (of both the completeness and the soundness). While the round complexity of ZKIPs has been studied greatly, no progress has been made for the communication complexity of those. This paper shows a perfect ZKIP whose communication complexity is 11/12 of that of the standard perfect ZKIP for a specific class of Quadratic Residuosity.

This paper presents two methods for securely realizing caller-authenticated and callee-specified calls over telecommunication networks with terminals that accept IC cards having KPS-based cryptographic functions. In the proposed protocols, users can verify that the partner is the proper owner of a certain ID or a certain pen name. Users' privacy is protected even if they do the caller-authenticated and callee-specified calls and do not pay their telephone charge in advance.

Recent progress on photoexcited process applications to fabricating of VLSI and flat panel devices in Japan has been reviewed. The excimer laser melt technique makes it possible to form large-grain poly-Si film on a glass substrate, improving TFT electrical characteristics, and to fill metals into high-aspect-ratio contact holes in VLSI metallization. Scanning of CW laser in poly-Si film led to growth of a single-crystal Si layer on SiO2 to fabricate 3-D (dimensional) devices successfully. Direct writing with pyrolytic reaction was put into practice for interconnection restructuring. In the photochemical process, lower temperature epitaxial growth of Si and dry cleaning of a Si wafer employing Hg lamp irradiation were noted. Directional etching was performed by sidewall film formation, while resolution of better than 0.5 µm was difficult to obtain due to diffraction limit. It was proposed that higher resolution would be obtained by introduction of a nonlinear process which enhanced pattern contrast.

In this paper a recursive form of Welch-Berlekamp (W-B) algorithm is provided which is a novel and fast decoding algorithm.

High-Definition Television (HDTV) 2 million pixel solid state image sensors with high performances are realized, applicable for 1 inch optical format. Key technical aspects of HDTV image sensors are suppression of smear level by maintaining large optical aperture and high readout signal rate by introducing a dual channel horizontal register. From such a perspective, new HDTV image sensors such as Stack CCD, Frame-Interline Transfer (FIT) CCD and Charge Modulation Device (CMD) are developed.

In 1990, Menezes, Okamoto and Vanstone proposed a method that reduces EDLP to DLP, which gave an impact on the security of cryptosystems based on EDLP. But this reducing is valid only when Weil pairing can be defined over the m-torsion group which includes the base point of EDLP. If an elliptic curve is ordinary, there exists EDLP to which we cannot apply the reducing. In this paper, we investigate the condition for which this reducing is invalid.

A system is constructed for the processing of question-answer dialogue as a subsystem of the speech response device. In order to increase the adaptability to dialogue topics, rules for dialogue processing are classified into three groups; universal rules, topic-dependent rules and task-dependent rules, and example-based description is adopted for the second group. The system is disigned to operate only with information on the content words of the user input. As for speech synthesis, a function is included in the system to control the focal position. Introduction and guidance of ski areas are adopted as the dialogue domain, and a prototype system is realized on a computer. The dialogue example performed with the prototype indicates the propriety of our method for dialogue processing.

This paper reviews the development of low temperature poly Si TFT, scattering light valves addressed by TFTs and a brighter video projection system using them, with the attensin of their optical aspects. The first includes main feature which are laser induced crystallization of PECVD a-Si in almost entirely solid phase by high speed scanning CW Ar laser beam. The second includes photo-polymerization induced phase separation method for the preparation of liquid crystal polymer composite (LCPC) material and scattering light valve with low driving voltage of 6 Vrms. The last gives a brighter video screen image with high contrast ratio and includes higher light efficiency through LCPC light valves and projection lens unit by about four times than that of conventional LC light valves with polarizers.

In this paper, we investigate the discrepancy between a serial version and a parallel version of zero-knowledge protocols, and clarify the information "leaked" in the parallel version, which is not zero-knowledge unlike the case of the serial version. We consider two sides: one negative and the other positive in the parallel version of zero-knowledge protocols, especially of the Fiat-Shamir scheme.

We have demonstrated the successful fabrication of the monolithic integration of a GaAs metalsemiconductor field-effect transistor (MESFET), an AlGaAs/InGaAs laser and a p-n photodetector grown on a SiO2 backcoated p-Si substrate using selective regrowth by metalorganic chemical vapor deposition (MOCVD). The use of SiO2 backcoated Si substrate is effective in suppressing unintentional Si autodoping and obtaining a good pinch-off GaAs MESFET. The MESFET with 2.5400 µm2 gate exhibited a transconductance of 90 mS/mm and a threshold voltage of 2.2 V. The reliability of the laser on the Si substrate can be improved by the strain-relieved AlGaAs/InGaAs laser with the InGaAs intermediate layer. The longest lifetime of the laser is 8 h at 27. During the GaAs layer growth, the p-n photodetector is formed near the surface of the p-Si substrate by diffusing the As atoms.

A context-sensitive method to predict linguistic expressions in the next utterance in inquiry dialogues is proposed. First, information of the next utterance, the utterance type, the main action and the discourse entities, can be grasped using a dialogue interpretation model. Secondly, focusing in particular on dialogue situations in context, a domain-dependent knowledge-base for literal usage of both noun phrases and verb phrases is developed. Finally, a strategy to make a set of linguistic expressions which are derived from semantic concepts consisting of appropriate expressions can be used to select the correct candidate from the speech recognition output. In this paper, some of the processes are particularly examined in which sets of polite expressions, vocatives, compound nominal phrases, verbal phrases, and intention expressions, which are common in telephone inquiry dialogue, are created.

Recent progress in high-speed semiconductor devices and integrated circuits (ICs) has outpaced the conventional measuring and testing instruments. With advent of ultrashort-pulse laser technology, the electro-optic sampling (EOS) technique based on the Pockels effect has become the most promising solution way of overcoming the frequency limit, whose bandwidth is approaching a terahertz. This paper reviews recent progress on the research of the EOS technniques for measuring ultrahigh-speed electronic devices and ICs. It describes both the principle of the EOS and the key technologies used for noncontact probing of ICs. Internal-node measurements of state-of-the-art high-speed ICs are also presented.

This paper was written for LSI engineers in order to demonstrate the effect of optical interconnections in LSIs to improve both the speed and power performances of 0.5 and 0.2 µm CMOS microprocessors. The feasibilities and problems regarding new micronsize optoelectronic devices as well as associated electronics are discussed. Actual circuit structures clocks and bus lines used for optical interconnection are discussed. Newly designed optical interconnections and the speed power performances are compared with those of the original electrical interconnection systems.

Breakdown fields and the charges to breakdown (QBD) of oxides increased after UV/Cl2 pre-oxidation cleaning. This is due to decreased residual metal contaminants on silicon surfaces in the bottom of the LOCOS region after wet cleaning. Treatment in NH4OH, H2O2 and H2O prior to UV/Cl2 cleaning suppressed increases in surface roughness and kept leakage currents through the oxides after UV/Cl2 cleaning as low as those after wet cleaning alone. The large junction leakage currents--caused by metal contaminants introduced during dry etching--decreased after UV/Cl2 cleaning which removes the contaminated layer.

Fabrication of 0.2 to 0.3 µm features is vital for future ultralarge scale integration devices. An area of particular concern is whether optical lithography can delineate such feature sizes, i.e., less than the exposure wavelength. The use of a phase shift mask is one of the most effective means of improving resolution in optical lithography. This technology basically makes use of the interference between light transmitting through adjacent apertures of the mask. Various types of phase shift masks and their imaging characteristics are discussed and compared with conventional normal transmission masks. To apply these masks effectively to practical patterns, a phase shifter pattern design tool and mask repair method must be established. The phase shifting technology offers a potential to fabricate 0.3 µm features by using the current i-line stepper, and 0.2 µm features by using excimer laser stepper.

A new direct projection patterning technique of aluminum using synchrotron radiation (SR) is proposed. It is based on the thermal reaction control effect of SR excitation. In the case of the Si surface, pure thermal growth is possible at 200, however, this growth is suppressed perfectly by SR irradiation. On the other hand, Al growth on the SiO2 surface is impossible at the same temperature thermally, however, SR has an effect to initiate thermal reaction. Both new effects of SR, suppression and initiation, are clarified to be caused by atomic order level thin layers formed from CVD gases by SR excitation on the surfaces. By using these effects, the direct inverse and normal projection patterning of Al are successfully demonstrated.

We indicate the existence of optimum expanded mode field diameters in thermally-diffused expanded core (TEC) fiber. The optimum ranges under our experimental conditions were from 14µm to 18µm for both 1.3µm-single-mode fiber and 1.55µm-dispersion-shifted fiber. By applying the TEC fiber fabricated in our experimental conditions to a multifiber connector, the connection loss can be reduced to less than 0.2dB without improving fiber and connector ferrule fabrication accuracy.

Thin- and ultra-thin-film SOI MOSFET's are promising candidates to overcome the constraints for future miniaturized devices. This paper presents simulation results for a 0.1 µm gate length SOI MOSFET structure using a two-dimensional/two-carrier device simulator with a nonlocal model for the avalanche induced carrier generation. For the suppression of punchthrough effect in devices with a channel doping of 1 1016 cm-3 and 5 nm thick gate oxide it is found that the SOI layer thickness has to be reduced to at least 20 nm. The thickness of the buried oxide should not be smaller than 50 nm in order to avoid the degradation of thin SOI performance advantages. Investigating ways to suppress the degradation of the sub-threshold slope factor at these device dimensions it was found in contrast to the common expectation that the S-factor can be improved by increasing the body doping concentration. This phenomenon, which is a unique feature of thin-film depleted SOI MOSFET's, is explained by an analytical mode. At lower doping the area of the current flow is reduced by a decreasing effective channel thickness resulting in a slope factor degradation. Other approaches for S-factor improvement are the reduction of the channel edge capacitances by source/drain engineering or the decrease of SOI thickness or gate oxide thickness. For the latter approach a higher permittivity gate insulating material should be used in order to prevent tunnelling. The low breakdown voltage can be increased by utilizing an LDD structure to be suitable for a 1.5 V power supply. However, this is at the expense of reduced current drive. An alternative could be the supply voltage reduction to 1.0 V for single drain structure use. A dual-gated SOI MOSFET has an improved performance due to the parallel combination of two MOSFET's in this device. A slightly reduced breakdown voltage indicates a larger drain electric field present in this structure.

Land mobile communications in Japan have shown remarkable progress in recent years. The total number of all types of radio stations has exceeded 750 million as of March, 1992 and more than 80% of them are used for land mobile communications. The more radio telecommunications becomes popular, the more demand for communicating at any time, at any place and with anyone, intensifies. Various new land mobile systems such as digital cellular telephones have been developed and to be introduced. These new systems are designed to promote effective frequency use in order to meet the exploding demand for it. The digitalization of land mobile communication systems will be the key technology which enable to bring the new possibility in the land mobile communications.