Abstract:
A system for conditioning an alkaline etching solution for reducing contamination in a silicon wafer etching process. The system includes a conditioning tank for mixing a conditioned alkaline etching solution, the conditioned alkaline etching solution including a conditioning chemical; a conditioning chemical introduction system configured to add the conditioning chemical to the conditioning tank; and a buffer tank for storing the conditioned basic etching solution before using the conditioned alkaline etching solution in an etching process.
Abstract:
In a manufacturing method of an electric motor, at a time of in-sequence arc welding each of one end of a plurality of lined-up connector terminals to each of a plurality of lined-up detection signal output terminals by a welding rod provided in a torch of an arc welding machine, the method connects each of the other ends corresponding to the respective one end of a plurality of connector terminals to each of earth terminals of the arc welding machine in sequence.
Abstract:
Anthraquinonic colorant represented by the formula (I): ##STR1## wherein Q.sup.1 and Q.sup.2 are each independently substituted or unsubstituted anthraquinonyl groups, Z.sup.1 and Z.sup.2 are bridge groups, A is an aromatic divalent group, and n is 0 or 1. The polarizing film which contains at least one colorant of the present invention in a hydrophobic resin, has excellent durability and moisture resistance.
Abstract:
The present invention relates to an electromagnetic brake. In an electromagnetic brake (11) comprising an electromagnetic brake body (13) having yoke members (15a and 15b) with a coil winding (14) and a brake movable member (16) formed of a magnetic material, which is disposed via an air gap (18) in a magnetic path formed by the electromagnetic brake body (13) and is fixed to a motor rotating shaft (2b), a magnetic fluid (20)is filled in the air gap (18), and a sealing member (19) for rotatably sealing the motor rotating shaft (2b) is disposed between the electromagnetic brake body (13) and the motor rotating shaft (2b) to prevent the magnetic fluid (20) from leaking, whereby the electromagnetic brake (11)is applied when the coil winding (14) is excited.
Abstract:
A novel HF cleaning method of silicon wafers is provided whereby the wafers are cleaned with a lowered level of particle contamination on the surface thereof. In the method silicon wafers are immersed in a HF bath, followed by immersion in a deionized water bath. The silicon wafers are lowered into and lifted out of each bath along a direction which is substantially vertical with respect to a surface of each bath at a rate of from 1 mm/sec to 50 mm/sec. During immersion, a vertical oscillation of the surface of each bath is maintained in the range of less than 4 mm.
Abstract:
An improved semiconductor wafer cleaning method capable of cleaning wafers without degrading the surface roughness of the wafers includes the steps of cleaning a polished wafer with an aqueous solution of hydrofluoric acid, then rinsing the wafer with ozone-containing water, and thereafter brush-scrubbing the wafer.
Abstract:
A method for a flatter semiconductor wafer free of ORP-observed irregularity and particles generated in handling on the back side of the wafer, in which an alkaline etching is adopted to utilize its advantage and a slight polishing step is combined to a conventional method of this kind. A deficiency of alkaline etching which brings about rougher surface irregularities on the surface of a wafer is eliminated by the use of the step of slight polishing on the back surface after the etching step and the inherent advantage stands without a loss, so that particle generation from the back surface of a semiconductor wafer in handling is much reduced and what's more a flatter semiconductor wafer is realized and a yield of an electronic device fabrication is increased.
Abstract:
Anthraquinonic colorant represented by the formula (I): ##STR1## wherein Q.sup.1 and Q.sup.2 are each independently substituted or unsubstituted anthraquinonyl groups, Z.sup.1 and Z.sup.2 are bridge groups, A is an aromatic divalent group, and n is 0 or 1. The polarizing film contains at least one colorant of present invention in a hydrophobic resin. The film has excellent durability and moisture resistance.
Abstract:
In a manufacturing method of an electric motor, at a time of in-sequence arc welding each of one end of a plurality of lined-up connector terminals to each of a plurality of lined-up detection signal output terminals by a welding rod provided in a torch of an arc welding machine, the method connects each of the other ends corresponding to the respective one end of a plurality of connector terminals to each of earth terminals of the arc welding machine in sequence.
Abstract:
A method of purifying an alkaline solution includes dissolving metallic silicon and/or silicon compounds in the alkaline solution and non-ionizing metallic ions in the alkaline solution with reaction products generated when the metallic silicon and/or silicon compounds are dissolved therein. This purifying method is capable of remarkably decreasing metallic ions in the alkaline solution at a low-cost by an easy operation. A method of etching semiconductor wafers includes purifying an alkaline solution by non-ionizing metallic ions in the alkaline solution and etching the semiconductor wafers by using the purified alkaline solution. According to this etching method, the metallic contamination level due to the etching of the semiconductor wafers is greatly decreased, there being neither deterioration in the wafer quality nor deterioration in the characteristic of the semiconductor device.