Abstract: A method for growing stoichiometric lithium niobate and lithium tantalate single crystals is provided. A crystal growing apparatus that includes a long crucible with a separation member therein is used. A solid feed material is quenched from a molten state, solidified in batches or sintered before charged in the long crucible to obtain substantially stoichiometric solids. The separation member divides the long crucible into a melting zone and a feeding zone located under the melting zone, and it could effectively prevent bubble formation in the growing crystal. The stoichiometry of the axial and radial composition can be well controlled, and the control of the diameter of the crystal body is easily achieved as well.

Abstract: Additional charge of a solid raw material 13 in the shapes of granules/lumps, low in raw material cost, and with no risk of cracking, is performed into a molten raw material 14 in a crucible in a static manner without solidifying a surface of the molten raw material 14 in the crucible 3. A bottom of a cylindrical raw material vessel 10 made of a material non-meltable when being in contact with the molten raw material 14 in the crucible 3 is closed with a bottom cover 11 made of a material meltable and removable when being in contact with the molten raw material 14 in the crucible 3. The raw material vessel 10 in a state of being filled with the solid raw material 13 in the shapes of granules/lumps is hung down above the crucible 3 to immerse the lower portion thereof into the molten raw material 14 in the crucible 3.

Abstract: In a method for growing a single crystal by bringing a seed crystal (4) into contact with a melt (2) of raw materials melted under heating in a crucible (1) a blade member (5) or a baffle member in disposed in the raw material melt (2) in the crucible (1) and a single crystal is grown by pulling up it with rotating the crucible (1) to thereby grow various single crystals including CLBO from the highly viscous raw material melt (2) as high quality and high performance crystals.

Abstract: An inexpensive method of coating silicon shot with boron atoms comprises (1) immersing silicon shot in a boron dopant spin-on solution comprising a borosilicate, a polymer precursor, and a volatile solvent, and (2) removing the solvent so as to leave a polymeric coating containing borosilicate on the shot. A precise amount of this coated shot may then be mixed with a measured quantity of silicon pellets and the resulting mixture may then be melted to provide a boron-doped silicon melt for use in growing p-type silicon bodies that can be converted to substrates for photovoltaic solar cells.

Abstract: A low temperature process for forming a metal doped silicon layer in which a silicon layer is deposited onto a substrate at low temperatures, with a metal doping layer then deposited upon the silicon layer. This structure is then annealed at low temperatures to form a metal doped semiconductor having greater than about 1×1020 dopant atoms per cm3 of silicon.

Abstract: An object of the invention is to provide a quartz glass crucible for pulling up silicon single crystal and a method for producing the same, suitable for improving the productivity of the crucible and the quality of the silicon single crystal, which, by forming a crystalline layer on the inner surface of the quartz glass crucible during pulling up silicon single crystal, prevents degradation from occurring on the inner surface of the crucible and increases the ratio of single crystal while preventing the dislocation from forming on the single crystals.

Abstract: A process forms a single crystal silicon ingot from varying sized pieces of polycrystalline silicon source material according to the Czochralski method. The process comprises placing into a crucible on the bottom a generally polygonal-shaped concentric array of rod-shaped polycrystalline silicon pieces having obliquely cut ends. The method of stacking the polycrystalline silicon pieces in the crucible allows for a denser packing of silicon in the crucible, can be accomplished in a quicker time then conventional packing methods, and has the potential for less damage to the crucible bottom, when comparing to standard packing methods using a size assortment of irregular shaped silicon pieces.

Abstract: A process for preparing a silicon melt in a crucible for use in growing a single crystal silicon ingot by the Czochralski method. The crucible is first loaded with chunk polycrystalline silicon and heated to partially melt the load. Granular polycrystalline silicon is then fed onto the exposed unmelted chunk polycrystalline silicon to complete the charge of silicon in the crucible. The granular polycrystalline silicon is intermittently delivered using a plurality of alternating on-periods and off-periods. During each on-period, granular polycrystalline silicon is flowed through a feed device that directs the granular polycrystalline silicon onto the unmelted chunk polycrystalline silicon. During each off-period, the flow of the granular polycrystalline silicon is interrupted. The loaded chunk polycrystalline silicon and the fed granular polycrystalline silicon are melted to form the silicon melt.

Abstract: A stoichiometric single crystal of lithium niobate or lithium tantalate is produced by pulling a single crystal of lithium niobate or lithium tantalate having a molar fraction of Li2O/(Nb2O5+Li2O) or Li2O/ (Ta2O5+Li2O) of at least 0.490 and less than 0.500, from a melt of a composition having a molar excess of Li over a stoichiometric composition of lithium niobate or lithium tantalate. The single crystal has 0.1 to 3 mol % of at least one element selected from the group consisting of Mg, Zn, Sc and In based on a total amount of elements Nb and Li, or a total amount of elements Ta and Li. The single crystal has substantially no absorption in the visible light region.

Abstract: Crystal growth apparatus comprising a crucible for containing a supply of molten material from which the crystal may be grown and first reflection means for receiving radiation directed along an input path and reflecting radiation towards second reflection means, whereby the second reflection means reflect output radiation along an output path. The first and second reflection means are arranged at or in close proximity with the surface of the molten material such that during crystal growth they maintain a substantially constant position relative to the surface of the molten material. The apparatus may comprise support means for supporting the first and second reflection means, whereby the support means are arranged to float on the molten material. The apparatus may be a single crucible apparatus or a double crucible apparatus.

Abstract: The present invention aims to improve thermal efficiency and to reduce melting time when a raw material in an auxiliary crucible is heated and melted by induction heating method. When an initial raw material 30a is at low temperature and its conductivity is relatively low, a conductive carbon cylinder 2 is arranged at such a height as to cover the entire side wall of the auxiliary crucible 1, and when high frequency current is applied on a high frequency coil 3, secondary induction current is generated on the carbon cylinder 2. Then, Joule heat is generated on the carbon cylinder 2 by the secondary induction current, and heat of the carbon cylinder 2 is transmitted to the raw material inside via the auxiliary crucible 1. Thus, the raw material is heated, and melting is started. When the raw material is melted, an insulating ceramic base 4 is arranged at such a position as to cover the entire side wall of the auxiliary crucible 1.

Abstract: A process for dendritic web growth is described. The process includes providing a melt, growing a dendritic web crystal from the melt, replenishing the melt during the step of growing the dendritic web crystal, and applying a magnetic field to the melt during the step of growing the dendritic web crystal.

Abstract: A crystal pulling unit for the production of a crystal block has a recharging tube (7), via which granulate (17) enters into a crucible (2) with a melt (3), located within a container (1). This recharging tube (7) has an annular space (20) between an inner wall (18) and an outer wall (19), which is open on the lower front side of the recharging tube (7) and is connected with the protective gas source (13) to supply protective gas. This protective gas cools the recharging tube (7) and around its outlet, forms a gas mist that prevents the entry of finer fractions of the charging material into the pulling space.

Abstract: A crystal pulling unit for the production of a crystal block has a recharging tube (7), via which granulate (17) is introduced into a crucible (2) with a melt (3), located inside a container (1). A fine-dust separator (8) is located in the recharging tube (7) outside the container (1); the separator works like an air classifier and, by means of a protective gas cushion, removes fine dusts from the granulate (17). This counters the danger of clogging of the recharging tube (7) by the caking of the recharging material.

Abstract: A method of loading a crucible, comprises loading at least one polycrystalline silicon rod into the crucible. Lump and/or granular polycrystalline silicon may also be loaded into the crucible. Especially when loaded into the crucible in a close-packed pyramidal configuration, a high loading density is achieved.

Abstract: A method of an apparatus for automatically and rapidly feeding raw material into a quartz crucible in manufacture of single-crystal silicon by CZ method. After a draining hose 203 is disposed in a quartz crucible 201, pure water is supplied from a water supply hose 204, and the quartz crucible 201 is conveyed onto a turn table 213 installed under a container 210. At this time, the quartz crucible 201 is rotated, and lump raw material 209 is fed into the quartz crucible 201. Since buoyancy of the pure water is applied to the lump material 209, impacts caused by the falling lump material can be moderated, and therefore, damages to the quartz crucible 201 can be prevented. After feeding raw material is finished, the pure water is discharged through a draining hose 203, and then the draining hose 203 is retracted from the quartz crucible 201. Thereafter, the quartz crucible 201 is conveyed into a microwave oven 211 for drying.

Abstract: The amount of silicon feed material supplied to a silicon melt furnace in a silicon crystal web growing installation is controlled by providing a melt level reference signal, generating a melt level signal representative of the level of the molten silicon in the silicon melt furnace, and providing a feed rate control signal representative of the difference between the melt level signal and the melt level reference signal. The feed rate control signal is used in a open loop mode to advise an operator of the amount of adjustment needed to correct the melt level; and is used in a closed loop mode to control the feed rate of the silicon feed material to the furnace. The laser beam reflected off the melt surface is passed through a narrow bandpass filter to remove noise due to thermal radiation from the furnace. The melt level signals generated by a position detector are averaged and digitally filtered to eliminate erroneous data caused by mechanical vibrations and other noise sources.

Abstract: For the oriented solidification of molten silicon to form an ingot in a bottomless crystallization chamber (9, 41) with a cooling body (11), which can be lowered relative to the chamber, the flat bottom surface of a seed body (25) of solid silicon is laid on the surface of the cooling body. The top surface of the seed body (25) is melted, and the ingot is grown on top of it as the cooling body is lowered by relative motion with respect to the crystallization chamber (9, 41) at a rate which is dependent on the supply of additional silicon and the solidification rate. For the purpose of producing large ingots with a coarsely crystalline to monocrystalline structure, a seed body (25) with a crystalline structure selected from the group ranging from coarsely crystalline to monocrystalline is used. Either lump silicon is placed on top of the seed body (25) and melted by induction, or molten silicon is produced in a forehearth (37) and poured onto the seed body (25). The seed body (25) has a thickness of 0.

Abstract: The invention is an improved method and apparatus for growing crystals that incorporates an isolation valve between the growth and injection chambers to allow the growth chamber to be maintained at operating temperature and pressure while decoupling the injector chamber in order to make changes necessary to restart or advance the process. Separate heating elements in the injector assembly or chamber provide related heating control. Upper and lower load cells and programmable signal amplifiers are configured to weigh and output the dynamic weight range of the loss or gain of process materials of the growth chamber crucible and the injector assembly, and are connected by electrical slip rings or wireless means to a computer control system.

Abstract: A process for preparing a silicon melt from a polysilicon charge, for use in the production of single crystal silicon ingots by the Czochralski method, in a crucible which has a bottom, a sidewall formation, a centerline which is substantially parallel to the sidewall formation and which intersects a geometric centerpoint of the bottom, and a radius extending from the centerline to the sidewall formation. In the process, the crucible is loaded with chunk polysilicon to form a charge having a bowl-like shape, wherein initially the load generally slopes radially upwardly and outwardly from the centerline toward the sidewall formation to an apex and then slopes generally downwardly and outwardly from the apex to the sidewall formation. The bowl-shaped chunk polysilicon charge is heated to form a partially melted charge, and granular polysilicon is fed onto the partially melted charge to form a mixed charge of chunk and granular polysilicon.

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.

Abstract: A silicon monocrystal is manufactured according to the continuously charged Czochralski method in which a double crucible is used which includes an outer crucible and an inner crucible which communicate with each other through pores. A dopant is charged to the silicon melt stored in the double crucible before commencing pulling of a silicon monocrystal such that the ratio of the dopant concentration of the silicon melt stored in the outer crucible to the dopant concentration of the silicon melt stored in the inner crucible becomes greater than an effective segregation coefficient of the dopant. The silicon monocrystal is then pulled while silicon material is charged to the silicon melt within the outer crucible, during which the dopant concentration ratio becomes equal to the effective segregation coefficient and then becomes smaller than the effective segregation coefficient.

Abstract: A single crystal pulling method employing; a gas tight container, a double crucible for storing a semiconductor melt inside the gas tight container comprising an inter-connected outer crucible and inner crucible, and a source material supply tube suspended from an upper portion of the gas tight container and positioned so that a granulated or powdered source material can be added from a lower end opening thereof to the semiconductor melt inside the outer crucible, with the source material being injected into the source material supply tube together with an inert gas flowing towards the enclosed container, characterized in that said source material is injected under conditions where the flow rate N (1/min.multidot.cm.sup.2) of the inert gas is within the range 0.0048P+0.0264<N<0.07P, where P (Torr) is the internal pressure inside said gas tight container.

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: The principal construction of a single crystal pulling apparatus involves a chamber (gas tight chamber) inside of which is a double crucible 3 for storing a semiconductor melt 21, comprising an outer crucible 11 and an inner crucible 12 communicated with each other, and a source material supply tube 5 suspended from an upper portion of the chamber, and positioned so that granular source material 8 can be introduced from a lower end opening 5a thereof into the semiconductor melt 21 between the outer crucible 11 and the inner crucible 12. An incline portion 13 is provided at a lower end of the source material supply tube 5 on the inner crucible 12 side, for introducing source material 8 discharging from the lower end opening 5a to the semiconductor melt 21 in the vicinity of the side wall of the outer crucible 11.

Abstract: A method of growing a single crystal of semiconductor using a CZ growth technique, having a step (0<t<t1) wherein a single crystal of semiconductor is pulled while a source material is supplied continuously to maintain a constant amount of semiconductor melt, and a step (t2<t<t3) wherein the supply of source material is halted, and the single crystal of semiconductor is pulled using residual melt from the first step.

Abstract: A liquid material such as molten silicon is stored in a crucible. A liquid material, which is identical to and held in the same conditions as the liquid material in the crucible, is continuously supplied from an auxiliary crucible to the crucible to keep constant the surface level of the liquid material in the crucible. The liquid material is continuously pulled up from the crucible at a predetermined speed while the liquid material is being solidified into a solid material such as a ribbon-like thin web of single-crystal silicon.

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: The object of the present invention affords a method of feeding dopant and a dopant composition used therein for easily preparing single crystals having a desired doping concentration during semiconductor substrate fabrication.In accordance with the present invention, a water solution containing oxides of the dopant is first added to the liquid containing colloidal silica. The colloidal silica can adsorb the oxides of the dopant to form a dopant composition. Around rod-shaped polysilicon, that is polysilicon rod, the dopant composition is discontinuously coated on the periphery of the polysilicon rods spaced at constant intervals and then dried. When the polysilicon rods are melted in an apparatus for manufacturing single crystals by a heater, dopant is protected by the glassed silica without evaporation. Accordingly, the dopant can be provided at a predetermined concentration to sustain the grown single crystals having a doping concentration as required.

Abstract: A process is disclosed for continuously producing a single crystal by drawing downwardly a melt of a single crystal raw material, wherein a single crystal body grown from the melt is continuously pulled downwardly, and a plurality of single crystal products are continuously formed by intermittently cutting the single crystal body being downwardly moved.

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: Apparatus and methods for pulling a semiconductor crystal according to a Czochralski method are disclosed. The apparatus includes a crucible containing a melt, a crystal pulling mechanism which pulls the semiconductor crystal from the melt, a motor coupled to the crucible, and a control circuit for energizing the motor to rotate the crucible at a variable speed. The control circuit may energize the motor to rotate the crucible at a continuously varying acceleration and continuously varying rotational speed while the crystal pulling mechanism is pulling at least a portion of the semiconductor crystal from the melt in the crucible. The control circuit may also energize the motor to rotate the crucible at a rotational speed which monotonically increases and decreases.

Abstract: A process for preparing a molten silicon melt from polycrystalline silicon for use in producing single crystal silicon by the Czochralski method is disclosed. Polycrystalline silicon is initially loaded into a Czochralski crucible, and melted to form a partially melted charge which includes both molten silicon and unmelted polycrystalline silicon. The molten silicon has an upper surface above which the unmelted polycrystalline silicon is partially exposed. Granular-polycrystalline silicon is fed onto the exposed unmelted polycrystalline silicon in a manner sufficient to allow the granular-polycrystalline silicon to dehydrogenate while it is resident on the surface of the unmelted polycrystalline silicon and before it becomes immersed in the molten silicon. The granular-polycrystalline silicon and the unmelted polycrystalline silicon are then fully melted to form a molten silicon melt.

Abstract: A process for growing crystals at an enhanced rate comprising providing a dispersion of a fluid medium and seed crystals of a metal oxide, introducing feed material comprising a metal oxide into the dispersion and maintaining a uniform mixture of the seed crystals, the feed material and the fluid medium, the feed material having an average crystal size less than the average crystal size of the seed crystals, the feed material being added in an amount and at a rate whereby the seed crystals grow, the feed material providing a soluble nutrient species for deposition of the said crystal to effect crystal growth, the mixture of seed crystals and feed material being treated under conditions which stimulate crystal growth for a period of time sufficient to obtain a desired quantity of a product comprising at least one grown crystal having an average crystal size greater than the average crystal size of the seed crystal.

Abstract: Means for applying a plastic finishing layer to the surface of a composite article comprising an extruded plastic-based solid body reinforced by one or more bundles of reinforcing fibers, these bundles being affixed to its surface, comprising a ring (1), the entry diameter (2) of which is greater than its exit diameter (3), the internal surface (4) of the said ring furthermore providing a decreasing variation in the internal diameter between its entry and its exit; method of applying a finishing layer, in which method these means are used, and coated composite article.

Abstract: New single crystals of ZnGeP.sub.2 are grown by a chemical vapor transport process from bulk synthesized polycrystalline ZnGeP.sub.2 using the LEK process with a controlled injection of phosphorus. The synthesis of the bulk is based on direct injection of phosphorus through a B.sub.2 O.sub.3 encapsulant and reaction with the zinc germanium melt, resulting in synthesis of a large melt (350 g) of ZnGeP.sub.2. When crystallization is followed by cooling the congruent melt down through the .alpha.-.beta. transition temperature (952.degree. C.) as is typical for bulk growth processes, the result is the growth of partially disordered material. This material is placed in a two zone heated furnace where iodine is used to transport the intermediate product to the growth zone where the single crystals grow, at a temperature below the .alpha.-.beta. phase transition. The resulting crystals produced contained a second cubic phase, which has not been reported previously.

Abstract: Herein disclosed are apparatuses for manufacturing compound semiconductor polycrystals comprising a pressure vessel, an upper shaft, a container for a first component fixed to the upper shaft, a heater around the container, a lower shaft, a susceptor and a crucible for charging a second component, a heater for the crucible and a communicating pipe for spatially connecting the container and the crucible optionally provided with a porous member at the lower extremity and/or a cylindrical member for confining a space over a part of the melt surface contained in the crucible from the remaining inner space of the vessel, the apparatuses permitting the substantial reduction of the reaction time and an improvement of the yield of the polycrystals due to the presence of the porous member and/or the cylindrical member separating the inner space of the vessel into two portions.

Abstract: To manufacture a low-carbon concentration GaAs wafer required for devices such as hall sensors, FETs, HEMTs etc. at a high production yield without deteriorating the semi-insulation characteristics thereof, a method of manufacturing a semi-insulation GaAs monocrystal by controlling carbon concentration during crystal growth by a simple method is disclosed. The method of manufacturing a semi-insulation GaAs monocrystal in accordance with liquid encapsulated Czochralski method, comprises the steps of: preparing a crucible (5) formed with a crucible body (6) and a small chamber (8) communicating with a lower part of the crucible body and a carbon heater (4) processed to reduce surface blow holes thereof; putting a melted GaAs liquid and a sealing compound B.sub.2 O.sub.3 in the crucible housed in an airtight vessel in such a way that the sealing compound B.sub.2 O.sub.

Abstract: A hopper is sized and shaped for reception in a crystal pulling apparatus for use in charging semiconductor source material to a crucible of the crystal pulling apparatus. The crystal pulling apparatus includes a pulling chamber, a growth chamber, an isolation valve operable to seal the growth chamber from the pulling chamber, and a crucible in the growth chamber. The hopper includes a bin constructed for containing a quantity of semiconductor source material. The bin has an opening in its bottom for delivery of the semiconductor source material from the bin to the crucible. A stopper constructed for closing the opening to prohibit passage of semiconductor source material from the bin is moved by a stopper actuating mechanism between a closed position and an open position. A connector attached to the hopper is constructed for temporarily mounting the hopper in the crystal pulling apparatus.

Abstract: The present invention employs the construction wherein a resistor heater is disposed inside a protective cylinder whose tip is open to a molten liquid packing zone of a crucible inside a pulling apparatus so that the resistor heater is above the tip of a lower portion and temperature setting can be made so as to be capable of fusing a starting material. Since the tip of the protective cylinder is positioned inside the molten liquid at the time of pulling of a single crystal, the gaseous phase portion inside the protective cylinder and the gaseous phase portion inside the pulling apparatus are separated apart by the molten liquid and are independent of each other and a starting material polycrystal rod loaded into the protective cylinder can be supplied to the molten liquid surface inside the crucible while being molten at the lower part of the protective cylinder by the resistor heater.

Abstract: A crucible is situated in a vacuum chamber and provided with a feeder for granulate material, heating elements for melting the material, and a crystal puller above the crucible. Measuring elements provide signals for a controller including a fuzzy processor utilizing an empirically determined data field to output a signal for the material feeder.

Abstract: A method and apparatus for pulling single crystals from a melt of semicontor material, in which a monocrystalline seed crystal grows to form a single crystal, the seed crystal being dipped into the melt and raised in a controlled manner in the vertical direction with respect to the melt, while the melt forms a molten pool which is held on a support body only by the surface tension and by electromagnetic forces due to an induction coil. This method includes recharging the melt with semiconductor material in solid or liquid form during the growth of the single crystal.

Abstract: A single crystal pulling apparatus based on Czochralski technique having a conduit for continuously supplying granular polycrystal material to the crucible and a vertical purge tube suspended centrally into the heating chamber, wherein the purge tube is vertically shiftable; a heat shield ring is connected to the lower end of the purge tube, and a cylindrical quartz partition ring made of a quartz glass containing no bubbles is held vertically by the heat shield ring in a manner such that the lower end of the quartz partition ring comes substantially lower than the lower end of the purge tube so that, by being dipped in the polycrystal melt, the partition ring isolates the interior surface of the melt from the exterior surface of the melt, over which latter the granular polycrystal material is poured.