Abstract: The drain voltage of an IGFET having a channel responsive to the change in physical quantity to be measured is negatively fed back to the gate terminal of the IGFET. The negative feedback loop includes series connection of a first amplifier having an amplification factor larger than unity and a second amplifier having an amplification factor smaller than unity. The interconnection point between the first and the second amplifiers is connected to the output terminal. There is provided a stable, highly sensitive and highly reliable semiconductor sensor.

Abstract: A differential pressure measuring transducer assembly including a measuring diaphragm formed of semiconductor material having gauge resistance elements on one surface thereof and a central boss area of large thickness and a peripheral support flange on the other surface thereof defining therebetween an annular portion of small thickness. The measuring diaphragm is attached at the peripheral support flange to a glass support member and a metallic support member formed with pressure conducting bores respectively communicating with each other. The metallic support member is formed of material having a Young's modulus substantially equal to that of the measuring diaphragm.

Abstract: A strain gauge is formed on one main surface of a semiconductor single crystal substrate while an insulating oxide film is formed on the other main surface of the substrate. A metal junction layer including several layers inclusive of eutectic alloy layers is formed on the surface of the insulating oxide film and the thus prepared structure is mounted on a metal strain generator. By heating this assembly to temperatures approximating to the eutectic point of the eutectic alloy layer, the semiconductor substrate and the metal strain generator are joined together.

Abstract: A pressure transducer comprising a silicon diaphragm on which a semiconductor strain gauge is formed and which has a diaphragm portion deformable in response to a pressure, an insulating support which is made of borosilicate glass having the silicon diaphragm rigidly mounted thereon and which is provided with a pressure introducing hole in its central part, a metallic support which is cylindrical, which is made of an iron-nickel alloy similar in the thermal expansion coefficient to the borosilicate glass and on which the glass insulating support is rigidly mounted, and a metallic housing within which the integrated structure consisting of the silicon diaphragm, the glass insulating support and the metallic support is arranged; the silicon diaphragm, the insulating support and the metallic support being joined by the anodic bonding, the metallic support being rigidly welded to the metallic housing at its lower end part.

Abstract: A semiconductor substrate has a major surface, another major surface on the opposite side of the first major surface, a strain gauge stripe formed in the central portion of the second major surface by diffusing an impurity therein, and electrodes connected to the strain gauge stripes. These strain gauge stripes are spaced from the peripheral edge of the second major surface by a distance greater than 1/3 of the length of the same major surface. The first major surface of the semiconductor substrate is bonded to an elastic metal load plate.

Abstract: A semiconductor pressure transducer comprising a disc-shaped pressure-responsive diaphragm; a pair of radial strain gauge units having a piezoresistance effect, formed by injecting an impurity in the radial direction in the surface of the diaphragm; and a pair of tangential strain gauge units having a piezoresistance effect, formed by injecting an impurity in the tangential direction in the surface of the diaphragm, wherein the distance from the pair of the radial strain gauge units to the center of the circular diaphragm is greater than the distance from the pair of the tangential strain gauge units to the center of the circular diaphragm.

Abstract: 1,4-Diacyloxybutene-2 is produced with a high yield by reacting 1,3-butadiene with a carboxylic acid, for example, acetic acid, and molecular oxygen in the presence of a catalyst containing metallic palladium and at least one iodine-containing substance selected from the group consisting of iodine, iodic acid, iodates, for example, alkali metal iodates and substituted and unsubstituted ammonium iodate, and iodides, for example, hydrogen iodide, alkali metal iodide and substituted and unsubstituted ammonium iodides, the ratio in gram-atom, of iodine to palladium in the above-mentioned catalyst being 0.1 to 1.5:1.