Photolithographic packaging with selectively occupied repeatedtransfer (PL-Pack with SORT) for scalable film optical linkmultichip-module (S-FOLM)

"Photolithographic packaging (PL-pack) with selectively occupied repeated transfer (SORT)" is proposed for optoelectronic microsystem integration. PL-pack with SORT integrates different types of thin-film device pieces into one substrate with desired configurations using an all-photolithographic process. A process design example is presented for a scalable film optical link multichip-module (S-FOLM). A preliminary estimation reveals that PL-Pack with SORT will achieve III-V epitaxial material saving of <1/100 and module cost reduction of <1/10, compared with flip-chip-bonding-based packaging. The result indicates that the process will save on cost and resources simultaneously. A critical issue is how to simplify the procedure for distributing thin-film device pieces onto a substrate. SORT is found to reduce the distribution step count typically by factor of <1/10-1/10000 compared with the conventional one-by-one method. PL-pack with SORT will be extended to the 3R process (reduce, reuse, recycle), which is generally applied to a variety of device/module fabrications     

A Low Power Dissipation Technique for a Low Voltage OTA

This paper proposes a novel low power dissipation technique for a low voltage OTA. A conventional low power OTA with a class AB input stage is not suitable for a low voltage operation (±1.5 V supply voltages), because it uses composite transistors (referred to CMOS pair) which has a large threshold voltage. On the other hand, the tail-current type OTA needs a large tail-current value to obtain a sufficient input range at the expense of power dissipation. Therefore, the conventional tail-current type OTA has a trade-off between the input range and the power dissipation to the tail-current value. The trade-off can be eliminated by the proposed technique. The technique exploits negative feedback control including a current amplifier and a minimum current selecting circuit. The proposed technique was used on Wang's OTA to create another OTA, named Low Power Wang's OTA. Also, SPICE simulations are used to verify the efficiency of Low Power Wang's OTA. Although the static power of Low Power Wang's OTA is 122 W, it has a sufficient input range, whereas conventional Wang's OTA needs 703 W to obtain a sufficient input range. However, we can say that as the input signal gets larger, the power of Low Power Wang's OTA becomes larger.     

Effect of blending on liquefaction of coals

After solvent extraction of Taiheiyo, Miike and Balmer coals using wash oil under nitrogen atmosphere at 370 °C for 30 min, the extraction yield is always within the additivity law. Further studies used Yallourn, Soyakoishi, Taiheiyo, Horonai, Miike, Shin Yubari, Balmer coals and their blends which were hydrogenated in tetralin, wash oil or creosote oil, with or without catalyst, at 400–450 °C under 10 or 3 MPa of initial hydrogen pressure. When hydrogen is available, the additivity law exists for blended coals, but when the hydrogen supply is deficient, the experimental conversion of blended coals is always lower than calculated conversions. This may be due to the faster consumption of the hydrogen by more reactive coals and thus the less reactive coals were unable to react with hydrogen.     

Delayed failure of PH13-8Mo steel plated with AI-IVD

We have experienced failure of the bolts for aircraft made of PH13-8Mo steel. The failure occurred a short time after the bolts had been fastened for assembly of aircraft parts. These bolts had been aluminum plated with ion vapor deposition (IVD) process. Based on this trouble, delayed failure of PH13-8Mo steel plated with aluminum by IVD was studied to clarify the cause of the trouble. Sustained load tests were performed in distilled water with notched specimens made of PH13-8Mo steel on which aluminum was plated by the same IVD process as defective bolts. From the tests carried out on many heats of PH13-8Mo steel, aged at 783 K (510°C), the following results were obtained: (1) heats containing more than 1.16 pct aluminum exhibited premature delayed failure with a low stress level threshold; (2) the heats containing less than 0.025 pct carbon and less than 1.16 pct aluminum showed extensive scatter in the values of threshold stress; and (3) the heats containing more than 0.025 pct carbon and less than 1.16 pct aluminum did not exhibit the premature delayed failure even at high stress levels. From the measurement of electrical resistivity changes associated with isothermal aging of PH13-8Mo steel, it is evident that the low-temperature phase formed by aging plays an important role in delayed failure and formation of the phase is significantly influenced by carbon and aluminum contents in the steel. Microcracks were found to form on the aluminum film plated by IVD when stress was applied to the specimen. Therefore, a galvanic couple would be constructed between coated aluminum and PH13-8Mo steel with the presence of distilled water which penetrated through the cracks initiated when the load was applied to the specimen. Hydrogen necessary to give rise to the delayed failure is produced by the cathodically polarized condition. Notch toughness was also controlled by carbon and aluminum contents in PH13-8Mo steel; however, it is not thought that the decrease in notch toughness plays a significant role in the cause of delayed failure. It is particularly noteworthy that carbon in the steel is useful to prevent the delayed failure and to keep excellent notch toughness in PH13-8Mo steel aged to high strength levels. Y. ASAYAMA, formarly with Engineering, Nagoya Aircraft Works, Mitsubishi Heavy Industries, Ltd.     

Reactivity of coals in hydrogenation

Three coals of different rank (77.9–89.5 wt% C, daf) were hydrogenated at various temperatures to examine the influence of coal rank on the hydrogenation reactivity. Extraction of the heat treated coals with pyridine, benzene and n-hexane was also carried out to estimate the total amount of the intrinsic solvent-soluble fraction in the original coal. In the extraction of preheated coal, the largest amount of pyridine-soluble fraction was obtained for the coal of medium rank (83.9% C). This coal also showed the highest conversion, in terms of pyridine solubility, on hydrogenation. As the pyridine soluble material from hydrogenation must contain the intrinsic soluble fraction present in the original coal, it cannot be concluded that medium-rank coal shows the highest reactivity in hydrogenation. Conversion to benzene and n-hexane soluble materials is only slightly affected by the intrinsic soluble fraction, so it is better to estimate hydrogenation reactivity from the yields of these materials. On this basis, the lowest-rank coal shows the highest reactivity in hydrogenation.     

L10-disorder phase equilibria in the Fe-Pd system investigated by phenomenological calculation

The creep strength of advanced ferritic heat-resistant steels for ultra super critical (USC) power plants is significantly improved by the addition of Pd. It has been found by a detailed transmission electron microscopy (TEM) observation that fine precipitation of an Fe-Pd based L1₀-ordered phase within a lath-martensite grain possessing a certain crystallographic orientation relationship with the matrix is reponsible for the strengthening mechanism. Phenomenological calculation by combining the cluster variation method (CVM) with a Lennard-Jones (L-J) type pair interaction energy is herein attempted for the Fe-Pd binary system to evaluate L1₀-disorder phase equilibria as an initial step to investigate ternary systems. Some of the unknown parameters in the Lennard-Jones pair interaction energies are determined with the help of computations based on a combination of a thermodynamic database and experimental measurement of the latent heat for the L1₀-disorder transition, the latter from differential scanning calorimetry. The experimental L1₀-disorder transition temperature is well reproduced by incorporating a tetragonal distortion of the L1₀-ordered phase into the calculation. In addition, detailed atomistic information, which is indispensable in designing and controlling the morphology of the L1₀-ordered phase, is obtained by the present calculation.     

L10-disorder phase equilibria in the Fe-Pd system investigated by phenomenological calculation

The creep strength of advanced ferritic heat-resistant steels for ultra super critical (USC) power plants is significantly improved by the addition of Pd. It has been found by a detailed transmission electron microscopy (TEM) observation that fine precipitation of an Fe-Pd based L1₀-ordered phase within a lath-martensite grain possessing a certain crystallographic orientation relationship with the matrix is reponsible for the strengthening mechanism. Phenomenological calculation by combining the cluster variation method (CVM) with a Lennard-Jones (L-J) type pair interaction energy is herein attempted for the Fe-Pd binary system to evaluate L1₀-disorder phase equilibria as an initial step to investigate ternary systems. Some of the unknown parameters in the Lennard-Jones pair interaction energies are determined with the help of computations based on a combination of a thermodynamic database and experimental measurement of the latent heat for the L1₀-disorder transition, the latter from differential scanning calorimetry. The experimental L1₀-disorder transition temperature is well reproduced by incorporating a tetragonal distortion of the L1₀-ordered phase into the calculation. In addition, detailed atomistic information, which is indispensable in designing and controlling the morphology of the L1₀-ordered phase, is obtained by the present calculation.     

A CMOS Analog Multiplier Free from Mobility Reduction and Body Effect

This paper proposes a novel CMOS analog multiplier. As its significant merit, it is free from mobility reduction and body effect. Thus, the proposed multiplier is expected to have good linearity, comparing with conventional multipliers. Four transistors operating in the linear region constitute the input cell of the multiplier. Their sources and backgates are connected to the ground to cancel the body effect. Their gates are fixed to the same bias voltage to remove the effect of the mobility reduction. Input signals are applied to the drains of the input cell transistors through modified nullors. The simulation results show that THD is less than 0.8% for 0.6 V_p-p input signal at 2.5 V supply voltage, and that the 3 dB bandwidth is up to about 13.3 MHz.     

UPGRADING OF COAL-DERIVFD LIQUIDS. 2. CHARACTERIZATION OF UPGRADED LIQUIDS BY GAS CHROMATOGRAPHIC DISTILLATION

ABSTRACT

Gas chromatographic distillation (GCD) based ors ASTM 02887 has been applied to characterizing the boiling range distribution of upgraded coal-derived liquids. It has beer demonstrated that the GCD method based on ASTM D2887 can be used as a substitute for ASTM D2892. A variety of coal-derived liquids can be characterized and the procedure may be effective for estimating the degree of conversion as a means of screening for hydroconversion catalysts.     

UPGRADING OF COAL-DERIVFD LIQUIDS. 2. CHARACTERIZATION OF UPGRADED LIQUIDS BY GAS CHROMATOGRAPHIC DISTILLATION

Gas chromatographic distillation (GCD) based ors ASTM 02887 has been applied to characterizing the boiling range distribution of upgraded coal-derived liquids. It has beer demonstrated that the GCD method based on ASTM D2887 can be used as a substitute for ASTM D2892. A variety of coal-derived liquids can be characterized and the procedure may be effective for estimating the degree of conversion as a means of screening for hydroconversion catalysts.