Other

Canon Kabushiki Kaisha

Kazuo Tsubouchi

Hitachi Media Electronics Co., Ltd.

Fuji Photo Film Company, Limited

Semiconductor Research Foundation

Nobuo Mikoshiba

Kazuya Masu

Toshiyuki Azuma

Jun Hozumi

Tomohiko Shibata

Kazuyoshi Sugai

Tadahiro Ohmi

Nobumasa Suzuki

Takashi Shiba

Yasuo Cho

Suguru Kameda

Yoji Isota

Kensei Uehara

Hiroyuki Nakase

Makoto Nagao

Yuichiro Imanishi

Michio Yokoyama

Kazuma Soeta

Hiroaki Sasaki

Takeshi Tomioka

Tadashiro Ohmi

Yohei Hiura

Toshiyuki Takewaki

Hideki Matsuhashi

Kenji Wasa

Shuichi Tomabechi

Takumi Suetsugu

A piezoelectric thin-film acoustic wave device formed of a piezoelectric thin film of AlN on the +C plane and having the polarization strength of not lower than 0.63&#xd7;10F/V and an information processing unit using the same are disclosed. This is the result of the inventors having studied the factors other than the C-axis orientation affecting the electromechanical coupling factor and developing a method of improving the electromechanical coupling factor in view of the occasional fact that the electromechanical coupling factor cannot be improved by improving the C-axis orientation and the electromechanical coupling factor required for the piezoelectric thin-film acoustic wave device is not obtained. In such a case, the receiving sensitivity of the receiving system may be deteriorated and the transmission strength of the transmission system is required to be increased undesirably having an adverse effect on the power saving efforts.

Piezoelectric thin-film acoustic wave device and information processing unit using the same

In a code division multiple communication system which prevents the dropout of a whole packet and does not require the generation of a carrier from a received signal, under bad communication path, by generating an orthogonal code with chip synchronization from a correlation peak of a synchronization code sequence output from a surface acoustic wave matched filter, a preamble division of a spectrum spread signal is composed of plural synchronization burst. Each synchronization burst is composed of a synchronization packet division having the Barker code of 11 chips and a dummy division. The period of one synchronization burst (T) is set equally to the period of one symbol in a data division (T) which is modulated by the orthogonal sequential code of 64 chips. When the correlation peak of at least one from among plural synchronization code sequences is detected, the orthogonal code can be generated in accordance with the start timing of the first symbol in the data division.

Code division multiple access communication system

Process for forming amorphous titanium silicon nitride on substrate

An output side electrode of a surface acoustic wave matched filter with portions having different delay times between taps. The output side electrode may be provided by arranging parallelly a plurality of output side electrodes having different scales, different tap distances, or by forming output side electrodes in an inclined fashion or in a dog-leg shape viewed in a direction of an aperture length, or by arranging, between electrode fingers, thin films having different dimensions or thicknesses viewed in the direction of the aperture length, or by forming, between electrode fingers, recessed portions having different dimension or depth viewed in the direction of the aperture length. In the surface acoustic wave matched filter for use in a spread spectrum communication, it is possible to prevent a decrease in a correlation caused by a variation in a propagating velocity of a surface acoustic wave due to a temperature characteristic as well as by fluctuations in the propagating velocity for respective substrates or within a single substrate.

Surface acoustic wave matched filter

A spectrum diffusion signal including data representing a center frequency of an acoustic surface filter in a transmitter side is transmitted with its carrier-frequency being swept. When a receiver side receives a modulation signal, a spectrum diffusion signal including data representing a center frequency of an acoustic surface filter in a receiver side is transmitted on the carrier-frequency equal to the center frequency of the surface acoustic wave matched filter in the transmitter side included in the modulation signal. Thereafter, the transmitter side transmits spectrum diffusion signals having the carrier-frequency equal to the center frequency of the surface acoustic wave matched filter in the receiver side included in the modulation signal.

Communication system using a surface acoustic wave-matched filter

A code division multiple access apparatus which is capable of high-speed synchronization, is simple in construction and, moreover, achieves reduced consumption of electric power during standby. When a specific pattern contained in a signal received by a receiving antenna is detected by a SAW matched filter, a correlation peak is output from the filter. A bit synchronization signal generating circuit detects the correlation peak thereof and generates a synchronization signal after a set time has elapsed from the detection of the correlation peak. An orthogonal PN code generator generates a predetermined orthogonal PN code in accordance with the synchronization signal. Further, a carrier generator generates a carrier in response to the output of the SAW matched filter. This generated carrier is modulated by the output of the orthogonal PN code generator. Then, the signal received by the receiving antenna is multiplied together with the modulation output by a multiplier, integrated by an integrator and returned to its original baseband data form.

Code division multiple access apparatus

A radio IC card system includes an IC card and a toll collector. When an automobile with the IC card passes by a tollgate, the toll collector installed in the tollgate transmits a first radio signal which is spread modulated using a pseudorandom noise (PN) code from an antenna. The first radio signal is received by the antenna of the IC card and is transmitted to a surface acoustic wave (SAW) correlator. The SAW correlator extracts a PN code included in the received signal, and outputs a peak signal. An accumulation circuit accumulates the peak signal. A threshold discharger is activated to switch on a relay switch when the output voltage of the accumulation circuit exceeds a constant value. Thereby, the voltage of a battery is supplied to a data communication unit. Then, the identification code of the IC card and a record of tollgates by which the automobile has passed are transmitted via radio signal to the toll collector.

Radio IC card system

A radio data transmitter includes radio switching circuit which is activated in response to first radio signal having a predetermined particular pattern, and a data transmitter unit. The data unit transmits a first radio signal include a carrier modulated by predetermined data from an antenna when supplied with power in accordance with the activation of the radio switching circuit, and subsequently disconnect the power supply. In addition, a radio data receiver includes switch-activation to circuit for transmitting the first radio signal having the predetermined particular pattern, a receiving circuit for receiving the second radio signal including the data from the data transmitter unit activated by the first radio signal having the predetermined particular pattern, and a storage device for storing data received by the receiving circuit.

Radio data transmitter and receiver

A radio switching apparatus is provided which is actuated upon reception of a radio signal and which is capable zero or near-zero standby electric power consumption. The radio switching apparatus includes a receiving antenna; a surface-acoustic-wave device to which a signal received by the antenna is fed and which extracts a specific pattern contained in the signal; a storing circuit for storing output electric power of the surface-acoustic-wave device; and a switch circuit which is turned on when the output voltage of the storing circuit exceeds a set value.

Radio switching apparatus

Semiconductor device with enhanced thermal conductivity

A process and apparatus for forming an Al film of good quality according to the CVD method utilizing the reaction between alkyl aluminum hydride and hydrogen, which is an excellent deposited film formation process also capable of selective deposition of Al. Pressure in a deposition chamber is maintained from 10.sup.-3 to 760 Torr. Alkyl aluminum hydride and hydrogen gas are introduced at a partial pressure from 1.5.times.10.sup.-5 to 1.3.times.10.sup.-3 of the pressure in the chamber. Aluminum is deposited on a substrate in the chamber by heating the substrate sufficiently to decompose the alkyl aluminum hydride.

Process for forming deposited film by use of alkyl aluminum hydride

A process for forming a deposited film on a substrate according to the chemical vapor deposition method comprises previously forming excited species of a gas phase compound containing atoms which become constituents constituting said deposited film, supplying the excited species onto the surface of said substrate and effecting photoirradiation on said substrate surface, thereby forming the deposited film through the surface reaction.

Chemical vapor deposition apparatus

A gas-feeding device for feeding a starting gas for deposition-film-formation by the chemical vapor deposition method, comprising a container having a space for discharging the starting gas containing an organometallic compound by introduction of a carrier gas; a gas-introducing means connected to the container for introducing a carrier gas is described. A plurality of openings for introducing the organometallic compound into the container is also provided, wherein each opening is part of an atomizer employing a piezoelectric element to eject the organometallic compound in a mist state into the container where the carrier gas passes through the space, and a container is provided for storing the organometallic compound.

Gas feeding device for controlled vaporization of an organanometallic

A chemical vapor deposition process is disclosed comprising the steps of forming liquid droplets of a liquid raw material; injecting the liquid droplets through a plate member opening placed opposite to the surface of the substrate to vaporize the liquid droplets; and supplying a reaction gas that reacts with the vaporized raw material; and depositing a thin film on the substrate.

Growing community of inventors

Sendai, Japan

Kazuo Tsubouchi