A 1.2-ns HEMT 64-kb SRAM

A 1.2-ns emitter-coupled-logic (ECL)-compatible 64-kb static RAM using 0.60-μm gate high-electron-mobility-transistor (HEMT) technology was developed. To achieve fast access time, the memory cell array was divided into sixteen 4-kb memory planes and a data-line equalization technique was adopted. The chip power consumption was suppressed to 5.9 W by using three power supply voltages (-1.0, -2.0, and -3.6 V) and a normally off (E/D) source-follower buffer for the word driver circuit. A new device fabrication technique, the HEMT double-etch-stop process, enabled the RAM to be fabricated in simple and fewer processing steps and reduced the chip dimensions to 7.4×6.5 mm     

CMOS circuits for peripheral circuit integrated poly-Si TFT LCDfabricated at low temperature below 600°C

CMOS shift registers, buffers, and gray-scale representation circuits for integrated peripheral drive circuits of poly-Si TFT LCDs were fabricated at temperatures below 600°C on a glass substrate. The maximum operation frequency of the CMOS shift register was 1.25 MHz. The total power consumption of the 10 stage CMOS shift registers at a clock frequency of 46.8 kHz and a power supply voltage of 20 V was 10 μW, which is three orders of magnitude smaller than that of 10-stage nMOS shift registers. The rise and fall times of the CMOS buffers were proportional to the inverse of the channel width, and the write time of the gray-scale representation circuits was proportional to the line memory capacitance     

Japanese Earth Resources Satellite-1 synthetic aperture radar

The spaceborne synthetic aperture radar (SAR) to be launched on the Japanese Earth Resources Satellite-1 is described. The SAR is operated in the L-band. The mission is mainly dedicated to geological applications. The ground resolution of the processed image is designed as 18 m and the off-nadir angle required to meet geological applications is 35°. The design and performance of the key system parameters are discussed, along with the reasons for choosing such design parameters. The antenna is a thin-flat-foldable configuration that has a 11.9-m by 2.2-m aperture when extended in orbit. The transmitter, receiver, and signal processor are all of the solid-state type to achieve high reliability of operation. They transmit an 1100-W peak (minimum) chirp pulse and receive the return echos and process the echo signals into in-phase and quadrature data streams     

A 1/2-in CCD imager with lateral overflow-gate shutter

The design considerations and performance of an interline-transfer charge-coupled-device (IL-CCD) imager with a lateral overflow gate shutter are described. A 489(V)-pixel×670(H)-pixel 1/2-in IL-CCD imager is shown to have a variable shutter function, whose shutter speed is controlled successively from 1/60 to 1/15700 s by the timing of the overflow gate pulse. The device requires a low voltage of only 4 V and a simple overflow gate pulse to realize the shutter function without any undesirable die size enlargement. The key technology of the device is the self-aligned photodiode structure, which realizes a complete charge transfer. Combined with a microlens on the photodiode, the device can achieve high-definition or small-die-size imagers because of its high sensitivity     

The autoresonant peniotron with a quadrupole interaction circuit

In the autoresonant peniotron interaction, all of the electrons will be able to give almost all of their kinetic energy to an electromagnetic wave, resulting in a conversion efficiency of nearly 100%, if the condition of V_p=C is satisfied in an interaction circuit and the initial velocity ratio of electrons is correctly given as a function of the electron kinetic energy. A quadrupole circuit is proposed in which the above circuit condition is usually satisfied and the RF electric field distribution in a cross section is suitable for the peniotron interaction at the fundamental cyclotron frequency. The design procedure for the test tube with the circuit and some simulation results concerned with the tube's operation are described     

Epitaxial Growth of Nickel(II) Hydroxide on layer Silicate and Derived Nickel-(Layer Silicate) Nanocomposite

Nickel(II) hydroxide crystals were deposited on a substrate of layer silicates from the liquid phase by decomposing nickel(II) ammine complex solutions dispersed with expandable layer silicates; the (001) planes of the nickel(II) hydroxide aligned parallel to the basal (001) plane of the layer silicates. From these layer silicate complexes with nickel(II) hydroxide, nickel-coated layer silicate composite particulates were derived. Moreover, metal–ceramics alloys, composed of nickel containing uniformly dispersed layer silicates several tens of angstroms in thickness, were produced by sintering the metal-coated ceramic powders.     

Elimination of copper from the molten steel by NH3 blowing under reduced pressure

Based on the finding that blowing of NH₃ gas onto molten pure copper at atmospheric pressure causes an evaporation of an enormously high rate, attempts have been made to eliminate copper dissolved in molten steel by NH₃ gas blowing under reduced pressure. Typical behaviours of molten steel when attacked by NH₃ gas are boiling, splashing and, in a violent case, slopping from the crucible. These phenomena are accompanied by an immense increase in the surface area from which volatile species are able to evaporate and may be useful for vacuum metallurgical processes. In this investigation, the decuprization experiments have been conducted to measure the rate at which the copper level in the molten steel is reduced using a vacuum induction furnace and blowing NH₃ gas through a vertical water-cooled copper nozzle. The data were represented in terms of the amount of copper transferred from the melt to the gaseous phase per unit surface area and time. According to these experiments, complete decuprization was attainable confirming selective evaporation of copper from molten steel under reduced pressure. So far as the mechanism of copper elimination by NH₃ gas, besides the enhanced vacuum evaporation of metal by the cooling effect of endothermic decomposition of NH₃, the formation of volatile copper compound was suggested from the fact that the copper could be removed down to an extra-low level of several ppm, even under a residual gas pressure of the order of 10 Torr.     

Preparation,surface-active properties and acid decomposition profiles of a new “soap” bearing a 1,3-dioxolane ring

New soap-type surfactants bearing a 1,3-dioxolane ring were prepared in good yields by the acid-catalyzed condensation of 1-O-alkylglycerols (alkyl: decyl, dodecyl, tetradecyl, heptadecyl, octadecyl, orcis-9-octadecenyl) with oxocarboxylic acid esters, followed by alkaline hydrolysis without any expensive reagent and special equipment. These surfactants were soluble in alkaline water at room temperature. Their critical micelle concentrations were much smaller than that of sodium dodecanoate. An alkaline solution of the octadecyl homologue was nonfoaming, but the other homologues, including thecis-9-octadecenyl derivative, showed high foaming ability in alkaline solutions. The structural effect of these compounds on the area per molecule at the surface is also discussed. Because these surfactants contain a 1,3-dioxolane ring, they can be utilized as a new acid-decomposable type of cleavable surfactant. At pH 1, they decompose almost completely into nonsurface-active species after 80 min.     

Theory of the cos ø term in the Josephson tunneling current

The current-phase relation for the Josephson tunnel junction is investigated by using the time-dependent Ginzburg-Landau (TDGL) equations. The cos ø term is shown to have a negative coefficient and the same order of magnitude as the phase-independent term. The effect of the tunneling barrier is taken into account in terms of the boundary conditions of the order parameter and the electric potential at the junction; the new boundary conditions are derived by generalizing de Gennes' discussions for the dc Josephson effect to the time-dependent phenomena. The TDGL equations are solved on the assumption that the transmission coefficient across the junction is small enough and that the processes involved are quasi-stationary. It is concluded that the spatial and temporal variations of various quantities are of vital importance to an understanding of the nonequilibrium characteristics in the tunnel junction.