For clarifying theoretically the behaviour of GaAs/Al1-mGamAs heterojunction-CCD, one dimensional analysis of the channel potential is done, and the heterojunction-CCD charge-transfer process between two transfer-electrodes is represented by analytical method.
Noboru ISHIHARA Hiroyuki KIKUCHI Mamoru OHARA
A Monolithic amplifier IC with small phase deviation applying parallel feed back technique was developed by using high speed Si bipolar process technology. This IC achieves a phase deviation of 1.8, an S21 gain of 46 dB and a limiting output of 7.8 dBm at 1 GHz.
Terutaka TAMAI Mitsuo KOMINAMI
By applying the ellipsometric analysis, the relationships between the growth of contaminant film on contact surface and contamination time were clarified with respect to the contact resistance and formation of the film. Contamination parameters for reaction formulas which are concerned with growth laws of contamination films for sulfuration of Ag and for oxidation of Cu were deduced.
Akira MATSUZAWA Akihiro KANDA Kazuya KIKUCHI Haruyasu YAMADA
A distribution of offset voltage of transistor pairs having fine pattern emitter down to 0.5 µm wide required for a parallel A/D converter can digitize at more than 200 MHz were measured. Moreover, contributions of transistor parameters to offset voltage and a realization of the ultra-high speed A/D converter were discussed. As the result, it was shown that the main transistor parameter contributes to the offset voltages is a fluctuation of a current gain, and a contribution of a emitter contact resistance was not so large. And the realization of 6 bit, 1 GHz or 8 bit, 750 MHz A/D converter was obtained.
Shinzo MUTO Haruki UCHIDA Toshimasa TAKAUCHI
In this letter, the thin film dye laser with DFB oscillator, amplifier and mode filter has been studied. The system is simply constructed on the anisotropic crystal prism such as KDP and operates as a compact tunable solid dye laser.
Akira MATSUZAWA Yasuto NAKATSUGI Akihiro KANDA Haruyasu YAMADA
In order to realize highly accurate analog to digital conversion for EDTV, HDTV, and video-camera with low power consumption, a monolithic video-rate 8 bit parallel A/D converter has been developed using high-accuracy bipolar transistors with trench isolation. The A/D converter can digitize wide band video signals up to 10 MHz with high signal to nose ratio (45 dB at 10 MHz input) at high conversion rate of 40 MHz. Notwithstanding it contains 7000 bipolar transistors, it consumes only 250 mW and is formed with small chip size (2.73.9mm2).
Effect of annealing on electrical conductivity of sintered silicon carbide containing boron carbide and carbon was investigated. The silicon carbide was sintered at the temperature range of 1650-2150 for 0.5 hr in vacuum. Samples sintered at above 1980 were annealed in argon at 1750 to 2000 for 0.5 hr to 5 hrs. The electrical conductivity was measured for both non-annealed and annealed silicon carbide, and following results were obtained.(1) The electrical conductivity was reduced about one order of magnitude by annealing for silicon carbide sintered at above 2050.(2) The effect to annealing on electrical conductivity was maximum at 1950 of annealing temperature, and is saturated at 3 hrs of annealing time.
Akira IINO Mikio OGAI Kunihiro MATSUBARA
A few ppm of sodium and potassium contained in natural silica tube has been found to be removed during the deposition process in MCVD fiber, while remaining such alkalies in over-jacketed natural silica tube was pointed out to migrate into the germania doped core part during drawing process and to deteriorate resistivity against hydrogen.
Masaaki DOI Minoru KAWANO Isamu KATO Koki SATO
A new fabrication method of a star coupler has been described. It is fabricated by stacking polymer films and then sticking them by a heat press. Using this method, the star coupler can be produced very easily and has square core cross sections. The 5-port multimode star coupler made on an experimental basis has an output power variation of 0.9 dB and an insertion loss of 3 dB.
Tadashi KATO Ryoichi ARAI Shuichi TAKANAMI
A modified cosine equalization effective for equalizing both amplitude and phase has been developed with a simple circuit. It slims asymmetrical read-back waveforms in digital magnetic recording devices more effectively than without phase equalization.
Masahiro MURAGUCHI Kuniki OHWADA
A Ku-band monolithic voltage controlled oscillator (VCO) has been developed. All the circuit elements for the VCO, i.e., an FET, a control diode, an output matching circuit, a stabilizer, and associated circuitary were integrated on a single chip. This VCO is characterized by using a unique stabilizer. The VCO with its stabilizer has shown stable oscillations across a tuning bandwidth covering 12.30 to 12.80 GHz with control voltage of 1 to 3.5 V. The output terminal of the chip can be directly connected to 50 ohm loads and requires no additional attenuator or isolator to stabilize it.
This letter describes structural design of a ribbon-to-single-fiber fanout connector. Considering bending strain and bending loss applied to the fibers for fanout, the relationship between the number fibers in the ribbon and the minimum length for fanout has been clarified.
Fumio UENO Takahiro INOUE Yuji SHIRAI Mamoru SASAKI
A maximum and a minimum circuits with multiple inputs are proposed. The operating speeds of these circuits are independent of the number of the inputs. Since the proposed circuits consist of only NMOS transistors, they can be implemented in semi-custom IC forms. A potential application of these circuits is a real-time fuzzy controller.
Toshiyuki TANAKA Kiyotoshi YASUMOTO
A two-dimensional radiation by a relativistic sheet electron beam passing over a corrugated conducting surface is investigated. The leakage coeffcient and phase change of space-charge waves due to the radiation is calculated using a perturbation approach based on the multiple scales.
Yukihiro KIYOTA Kouji NUMADA Isamu KATO
We have fabricated SiN films with stoichiometric composition by double tubed coaxial line type microwave plasm chemical vapor deposition and have discussed the effects of the microwave power on the film qualities.
Toshiyuki KANO Hiroshi TANIGUCHI Hiroshi SAITO
A copper vapor laser performance by using a metal-vapor-complex reaction (CuAlBr3) is reported. The laser operation is obtained at a low temperature without external heating because of the AlBr3 vapors evaporation at a room temperature. The copper vapor laser using this metal-vapor-complex reaction has an advantage of deposition-free of a metalilc copper to the laser tube wall, which is different from the copper halide and the organometallic copper lasers.
Nobuo KUWABARA Tsuyoshi IDEGUCHI
An analytic expression of electromagnetic near field emitterd by a single current flow along a straight wire is derived to obtain the radiated EMI limit from the telecommunication lines connected to the equipment. The validity of the theory is tested in the experiment. Calculations show that the conversion factor between the electric field strength and the terminal voltage is not significantly changed by the wire length. A maximum conversion factor of about -30 dB in the frequency range of 0.1 -30 MHz is obtained.
Fumihiko ITO Tadatoshi TANIFUJI
A design principle of total reflection type optical switches with broad wavelength bandwidth using the plasma dispersion effect in GaAs is described. Wavelength dependent excess loss due to Goos-Hanchen shift in wavelength region from 1.3µm to 1.55 µm is reduced to within 0.1 dB with waveguide cross angle of 5 and injected current density of 16 kA/cm2.
Kentaro NAKAMURA Makoto ANDO Naohisa GOTO
A full-wave analysis of antennas with polarization grids is performed. Radiation patterns of antennas for two types of grids (straight strip and curved strip) are presented, where effects of the grid position and the grid paramenters are discussed.