Abstract:
In a pulling apparatus operated according to the multi-pulling method or CCZ method, granular silicon material is first fed to a feed pipe from a feeder so as to form stagnation of the granular silicon material in the feed pipe. The feeding of the granular silicon material from the feeder to the feed pipe is repeatedly commenced and stopped so as to maintain the stagnation of the granular silicon material. The feed rate of the granular silicon material from the feeder to the feed pipe is increased with time until the feed of the silicon material is completed. This prevents abrasion of a coating or lining provided on the inner surface of the feeder and also prevents damage of the feeder. In a pulling apparatus operated according to the Czochralski method, after causing granular silicon material to stagnate in the feed pipe, the crucible is lowered or the feed pipe is raised, while the stagnation of the granular silicon material is maintained, so as to form an unmolten layer of the granular silicon material on the molten or solidified surface of the silicon melt. The unmolten layer is then melted, and the granular silicon material is fed onto the unmolten layer through the feed pipe while the stagnation of the granular silicon material in the feed pipe is maintained. Accordingly, silicon material can be recharged without damaging the crucible, so that productivity and manufacturing yield of silicon monocrystals can be improved.
Abstract:
Apparatus for measuring the mechanical strength of a neck portion of a silicon seed crystal used for growing a silicon crystal by the Czochralski method includes a seed chuck for holding the seed crystal of a test sample and an end of a wire hung from an upper hook. A crystal holder which holds the other end part of the test sample from below is tied to a lower hook with another wire to support the holder. The apparatus includes means for pulling the hook at a given rate, and measuring means for continuously measuring tensile load. Such apparatus and the method thereby provide accurate measurement of mechanical strength of the neck portion of the silicon seed crystal with good precision and reproducibility. A single crystal ingot is grown under conditions affording good balance of productivity and safety.
Abstract:
An electro-optic device comprises a plurality of first electrodes provided on a top substrate and a second electrode provided on a bottom substrate, the first electrodes confronting the second electrode through electro-optical matter which will show electro-optical phenomena by the application of electric field, the first and second electrodes being connected through external impedance elements such as resistors or capacitors to a variable voltage source. In this electro-optic device, the electric field applied between the first and second electrodes are partially changed by various means, for instance, by making the areas of the first electrodes different, or by varying the values of the external impedance elements such as resistors or capacitors, as a result of which the electro-optical matter shows various electro-optical phenomena.
Abstract:
A high pressure resistant and water tight panel assembled tank consisting of unit panels, each unit panel is formed with a protrusion portion in the form of a pyramid or truncated pyramid progressively increasing its height toward a center of the square wall surface of the panel and has securing flanges at the peripheries of the panel. The unit panels consist of (a) bottom wall panels of which securing flanges are folded in a direction opposite to the extending direction of the protrusion portion and (b) side wall panels of which securing flanges are folded in a direction the same as that of the protrusion portion and having partially thicker portions, and the securing flanges of the wall panels embracing sealing seats therebetween are clamped together outside of the tank to form the assembled tank. Assembled tie rods and panels for mounting supply and drain pipings are incorporated in the tank to improve the pressure resistance of the tank and to facilitate assembling, settling, piping and cleaning of the tank.
Abstract:
An electro-optic device comprises a plurality of first electrodes provided on a top substrate and a second electrode provided on a bottom substrate, the first electrodes confronting the second electrode through electro-optical matter which will show electro-optical phenomena by the application of electric field, the first and second electrodes being connected through electrical elements such as resistors or capacitors to a variable voltage source. In this electro-optic device, the electric field applied between the first and second electrodes are partially changed by various means, for instance, by making the areas of the first electrodes different, or by varying the values of the electrical elements such as resistors or capacitors, as a result of which the electro-optical matter shows various electro-optical phenomena.
Abstract:
A recharger system including a feeder and a feed conduit recharge polycrystalline silicon granules into a crucible after a run or operation of growing a single crystal silicon rod by the Czochralski method, thereby to prepare for a next run of crystal growing. The amount of holdup or backed-up supply of the silicon granules in the feed conduit is detected by a sensor provided on the feed conduit. A smooth and high-rate feed of the silicon granules is ensured by controlling the feed rate of the silicon granules from the feeder to the feed conduit and/or a descending velocity of the crucible by signals generated in the sensor as a function of the amount of the holdup or backed-up supply in the feed conduit.
Abstract:
In a method of manufacturing a silicon monocrystal using a continuous Czochralski method, a silicon monocrystal is pulled from a silicon melt in a crucible while a silicon material is fed to the crucible. Supply of the silicon material is suspended until the temperature distribution of the silicon melt becomes stable after initiation of a straight body forming process, and the supply of the silicon material is commenced when the temperature distribution of the silicon melt has become stable. The feed rate of the silicon material is gradually increased until the feed rate becomes equal to a solidification rate of the silicon melt after the supply of the silicon material has been commenced. This method prevents the silicon monocrystal from becoming a polycrystal during the manufacture thereof.
Abstract:
A recharger system including a feeder and a feed conduit recharge polycrystalline silicon granules into a crucible after a run or operation of growing a single crystal silicon rod by the Czochralski method, thereby to prepare for a next run of crystal growing. The amount of holdup or backed-up supply of the silicon granules in the feed conduit is detected by a sensor provided on the feed conduit. A smooth and high-rate feed of the silicon granules is ensured by controlling the feed rate of the silicon granules from the feeder to the feed conduit and/or a descending velocity of the crucible by signals generated in the sensor as a function of the amount of the holdup or backed-up supply in the feed conduit.
Abstract:
A single crystal pulling apparatus having a wire which is used to pull a crystal is provided with a novel wire vibration prevention mechanism. The wire vibration prevention mechanism includes wire restriction devices which restrict the movement of the wire to movement in the vertical direction. The wire restriction devices may be mechanically driven in the horizontal direction in order to center the pulled crystal. The wire restriction devices are driven by pneumatic air cylinders. Use of the wire vibration prevention mechanism avoids the formation of deformed growth of the pulled crystal and thus reduces the occurrence of dislocations in the pulled crystal.
Abstract:
Organic fertilizers having a superior fertilizer response (or efficiency), and a higher nitrogen content but a lower water-insoluble type nitrogen content are prepared from spent liquors of sulfite pulp plants according to the method of the present invention. Said method comprises setting the solid matter concentration of said spent liquors in the reaction liquid consisting mainly of said spent liquors to 20-45% by weight and reacting therewith ammonia in an amount of 15-30 mol per 1 Kg of said solid matter, and oxygen or oxygen-containing gas at a reaction temperature of 90.degree.-120.degree. C. under a pressure of 4 Kg/cm.sup.2 or higher and lower than 10 Kg/cm.sup.2.