Shin-Etsu Handotai Co., Ltd.

Kiyotaka Takano

Hirotoshi Yamagishi

Masanori Kimura

Eiichi Iino

Izumi Fusegawa

Masahiro Sakurada

Ryoji Hoshi

Hiroyuki Kamada

Tomohiko Ohta

Koji Mizuishi

Kosei Sugawara

Tomohiko Oota

Kiyoshi Mitani

Hiroji Aga

Makoto Iida

Isao Yokokawa

Masahiko Urano

Nobuaki Mitamura

Akihiro Kimura

Kouji Kitagawa

Hitoshi Tsunoda

Wataru Yajima

Kazuya Yanase

Junya Tokue

Katsuhiko Ogino

Keisuke Mihara

Takahide Onai

A single crystal manufacturing including: main chamber; pulling chamber; thermal shield member provided so as to face a silicon melt; rectifying cylinder provided on the thermal shield member so as to enclose the silicon single crystal being pulled up; cooling cylinder provided so as to encircle the silicon single crystal being pulled up and including an extending portion extending toward the silicon melt; and cooling auxiliary cylinder fitted to inside of the cooling cylinder. The extending portion of the cooling cylinder includes a bottom surface facing the silicon melt. The cooling auxiliary cylinder includes at least a first portion surrounding the bottom surface of the cooling cylinder and a second portion surrounding an upper end portion of the rectifying cylinder. This enables provision of the apparatus capable of manufacturing a single crystal with a carbon concentration lower than that according to the conventional technologies.

Single crystal manufacturing apparatus

A single-crystal pulling apparatus includes: a pulling furnace having a heater and crucible; and a magnetic field generation device having superconducting coils, the device having four of the superconducting coils, two of the superconducting coils are in each of two regions divided by a cross section that includes an X axis being a direction of magnetic force lines at the central axis in the horizontal plane including all the coil axes of the four superconducting coils, and includes the pulling furnace central axis having line symmetry about the cross section, the four superconducting coils are all arranged so that the coil axes have an angle of more than −30° and less than 30° relative to a Y axis, the direction of the magnetic force lines thereof have line symmetry about the cross section, and in each of the regions, the two superconducting coils generate magnetic force lines in opposite directions.

Single-crystal pulling apparatus and single-crystal pulling method

A single-crystal pulling apparatus including: a pulling furnace having a central axis; and a magnetic field generation device arranged around the pulling furnace and having superconducting coils, the apparatus applying a horizontal magnetic field to the molten semiconductor raw material, two coil axes in the two pairs of the superconducting coils are included in a single horizontal plane, and when a direction of lines of magnetic force at the central axis of the pulling furnace in the horizontal plane is determined as an X axis, a center angle α having the X axis between the two coil axes is 100 degrees or more and 120 degrees or less. This makes it possible to reduce the height of the coils, to raise the magnetic field center close to the melt surface of the semiconductor raw material, and to obtain a single crystal having a lower oxygen concentration than conventional single crystals.

Single-crystal pulling apparatus with saddle-shaped superconducting coils and single-crystal pulling method

A method controls a resistivity of a grown silicon single crystal by using a dopant when the silicon single crystal is grown by CZ method, including the steps of initially doping with a primary dopant such that the silicon single crystal has a predetermined conductive type and additionally doping with a secondary dopant having a conductive type opposite to that of the primary dopant continuously or intermittently, according to a solidification rate expressed by (crystalized weight)/(initial weight of silicon raw material) while growing the silicon single crystal, wherein in the additional doping step, the additional doping with the secondary dopant is carried out when the solidification rate is a predetermined value &#x3b1; or more, while the crystal is not doped with the secondary dopant until the solidification rate reaches the predetermined value &#x3b1;.

Method for controlling resistivity and N-type silicon single crystal

A single-crystal pulling apparatus including a pulling furnace containing a crucible containing molten single crystal material, and a magnetic field generation device that is arranged around the furnace, has superconducting coils, and generates a magnetic field distribution. A magnetic flux density distribution on an X axis, which is a direction of magnetic force lines at the central axis in a horizontal plane, is a convex upward distribution, and a magnetic flux density on the X axis becomes 80% or less of a magnetic flux density set value at a crucible wall. Simultaneously, a magnetic flux density distribution on a Y axis, orthogonal to the X axis, is a convex downward distribution, and a magnetic flux density on the Y axis becomes 140% or more of the set value at the crucible wall when the magnetic flux density at the central axis in the horizontal plane is the set value.

There is provided a method for manufacturing a silicon single crystal, the method includes: a raw material melting step of melting polycrystalline silicon accommodated in a crucible to obtain a silicon melt; and bringing a seed crystal into contact with the silicon melt and pulling up the seed crystal to grow the silicon single crystal, wherein, after the raw material melting step and before the pulling step, there are performed: a cristobalitizing step of leaving the silicon melt at a predetermined number of rotations of the crucible with a predetermined gas flow rate and a predetermined furnace pressure to generate cristobalite while applying a magnetic field; and a dissolving step of partially dissolving the cristobalite by carrying out any one of an increase in number of rotations of the crucible, an increase in gas flow rate, and a reduction in furnace pressure beyond counterpart figures in the cristobalitizing step.

Method for manufacturing silicon single crystal

The present invention is an apparatus for producing a single crystal, growing the single crystal by the Czochralski method and comprising at least: a main chamber in which a crucible for accommodating a raw material melt and a heater for heating the raw material melt are arranged; a pulling chamber into which the grown single crystal is pulled and accommodated, the pulling chamber being continuously provided above the main chamber; and a cooling cylinder extending at least from a ceiling of the main chamber toward a surface of the raw material melt so as to surround the single crystal during pulling, the cooling cylinder being forcibly cooled with a cooling medium. As a result, there is provided an apparatus for producing a single crystal that can increase the growth rate of the single crystal by efficiently cooling the single crystal during the growth.

Apparatus for producing single crystal

The present invention provides an apparatus for producing single crystals according to the Czochralski method, the apparatus including a chamber that can be divided into a plurality of chambers; at least one of the plurality of divided chambers having a circulating coolant passage in which a circulating coolant for cooling the chamber circulates; and measuring means that respectively measure an inlet temperature, an outlet temperature, and a circulating coolant flow rate of the circulating coolant in the circulating coolant passage; the apparatus further including a calculating means that calculates a quantity of heat removed from the chamber and/or a proportion of the quantity of removed heat, from the measured values of the inlet temperature, outlet temperature, and circulating coolant flow rate; and a pulling rate control means that controls a pulling rate of the single crystal based on the resulting quantity of removed heat and/or the resulting proportion of the quantity of removed heat. The invention also provides a method for producing single crystals using the apparatus. Thus, an apparatus and a method for producing single crystals are provided for producing single crystals while easily stabilizing the crystal quality.

Apparatus and method for producing single crystals

An upper heater for use in the production of a single crystal, the upper heater having electrodes to which a current is supplied and a heat generating section which generates heat by resistance heating are provided, the upper heater being used when a single crystal is produced by a Czochralski method, the upper heater being placed above a graphite heater which is placed so as to surround a crucible containing silicon melt, wherein the heat generating section is ring-shaped and is placed so as to surround the crucible, and has slits formed from the inside and the outside of the heat generating section in a horizontal direction. As a result, the upper heater controls a crystal defect of the single crystal efficiently and improves the oxygen concentration controllability.

Upper heater, single crystal production apparatus, and method for producing single crystal

The present invention provides a method of producing an SOI wafer, comprising at least steps of forming an oxygen ion-implanted layer by implanting oxygen ions into a silicon wafer from one main surface thereof, subjecting the silicon wafer to oxide film-forming heat treatment to convert the oxygen ion-implanted layer into a buried oxide film, and thereby producing an SOI wafer having an SOI layer on the buried oxide film, wherein when the buried oxide film is formed in the silicon wafer, the buried oxide film is formed so that a thickness thereof is thicker than a thickness of the buried oxide film which the SOI wafer to be produced has, and thereafter the silicon wafer in which the thicker buried oxide film is formed is subjected to a heat treatment to reduce the thickness of the buried oxide film. Thereby, there can be provided a method of producing an SOI wafer in which a high quality SOI wafer having a buried oxide film of which a film thickness is thin and perfectness is high and an SOI layer of which crystallinity and surface quality are extremely good can be produced by using SIMOX method.

Method of producing SOI wafer and SOI wafer

The present invention provides an SOI wafer having at least an SOI layer, in which a plain orientation of the SOI layer is off-angled from {110} only in a direction to &#x3c;100&#x3e;, and an off-angle is from 5 minutes to 2 degrees, and a method of producing an SOI wafer comprising at least bonding a base wafer and a bond wafer consisting of a silicon single crystal, and forming an SOI layer by thinning the bond wafer, wherein the bond wafer is used where a plain orientation thereof is off-angled from {110} only in a direction to &#x3c;100&#x3e;, and an off-angle is from 5 minutes to 2 degrees. Thereby, there can be provided an SOI wafer having both high uniformity of film thickness and good micro-roughness to be suitable for fabricating high speed devices, and provided a method of producing the SOI wafer.

SOI wafer and a method of producing the same

Silicon single crystal with no crystal defect in peripheral part of

In a single crystal manufacturing method by a horizontal magnetic field applied CZ method wherein coils are disposed interposing a crucible coaxially with each other, the coils constituting superconductive electromagnets of a magnetic field application apparatus and the silicon crystal is pulled from melt in the crucible while applying a horizontal magnetic field to the melt; an elavation apparatus capable of finely adjusting relative positions of the superconductive electromagnets and the crcucible in a vertical direction is disposed. The descent of a central portion Cm in a depth direction of the melt is canceled by elevating the crucible with the elevating apparatus, the descent being accompanied with proceeding of process of pulling the single crystal, thereby a coil central axis Cc of the superconductive electromagnets always passes through the central portion Cm or below this portion. Compared with the conventional HMCZ method, an uniformity of an intensity distribution of the magnetic field applied to the melt is increased so that a suppression effect on the melt convection all over the crucible is enhanced.

Manufacturing method of single crystal and apparatus of manufacturing

A puller and method for crystal growth using the Czochralski technique in which a temperature profile and a history of thermal conditions of a growing crystal is controllable with ease and a good accuracy, which puller comprises a crucible containing raw material, heater for melting by heating the raw material and a heat insulating cylinder surrounding them, the heat insulating cylinder being cross-sectionally divided by an annular separation gap or gaps into parts and which method is applicable to growth of such a single crystal as of silicon, germanium, GaP, GaAs or InP in the puller. Methods for controlling a temperature profile and a history of thermal conditions of a growing crystal using the czochralski technique in the puller.

Method for producing a single crystal using czochralski technique

An apparatus for producing a silicon single crystal grown by the Czochralski method includes a main chamber having a round soulder interconnecting the upper end of a side wall and the lower end of a neck of the main chamber. The round shoulder has an inside surface so profiled as to form a portion of the periphery of an ellipse drawn about two foci which are composed of the upper end of a heater and a point of the longitudinal axis of a silicon single crystal being grown. The inside surface has a low emissivity. With the apparatus thus constructed, a silicon single crystal having a high dielectric breakdown strength of oxide film (SiO.sub.2) can be produced in a stable manner with high yield and productivity.

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Annaka, Japan

Kiyotaka Takano