Shin-etsu Handotai Co., Ltd.

Ryoji Hoshi

Izumi Fusegawa

Tomohiko Ohta

Susumu Sonokawa

Hiroyuki Kamada

Kosei Sugawara

Masahiro Sakurada

Kiyotaka Takano

Takao Takenaka

Masahiko Urano

Koji Kitagawa

Yutaka Kitagawara

Takahiro Yanagimachi

Yuuichi Miyahara

Masanori Takazawa

Kouichi Inokoshi

Hiroshi Takeno

Atsushi Iwasaki

Ken Aihara

Naoki Nagai

Tomosuke Yoshida

Fumio Tahara

Satoshi Tobe

Hisayuki Saito

Tetsuya Igarashi

Fumitaka Kume

Wataru Sato

Junya Tokue

Suguru Matsumoto

Shigemaru Maeda

Naohisa Toda

Toshirou Hayashi

Satoshi Ushio

A method for producing a silicon single crystal, wherein a silicon nitride powder is introduced into a raw material before start of melting and the silicon single crystal doped with nitrogen is pulled by Czochralski method, wherein nitrogen doping is performed while an upper limit amount of usable silicon nitride powder is limited based on an amount of carbon impurities contained in the silicon nitride powder so that a carbon concentration in the silicon single crystal is equal to or less than allowable value. This makes it possible to achieve the required nitrogen doping amount at low cost while achieving the low carbon-concentration specification.

Method for producing a silicon single crystal doped with nitrogen and having a controlled amount of carbon impurities

A method of producing a silicon single crystal, including pulling a silicon single crystal by Czochralski method while a magnetic field is applied to a raw material melt, including: setting a diameter on pulling the silicon single crystal to 300 mm or more, setting a growth axis direction of the silicon single crystal to &#x3c;111&#x3e;, and growing the silicon single crystal so as to satisfy a relation of 1096/D&#x2212;(0.134&#xd7;M+80&#xd7;R)/D&#x3e;0.7, wherein D [mm] is the diameter on pulling the silicon single crystal, M [Gauss] is a central magnetic field strength at a surface of the raw material melt, and R [rpm] is a rotation rate of the silicon single crystal. This makes it possible to produce a &#x3c;111&#x3e; crystal with favorable macroscopic RRG distribution and microscopic variation of resistivity.

Method of producing silicon single crystal, and silicon single crystal wafer

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 method for growing a silicon single crystal by a Czochralski method, includes: conducting preliminary examination of growth conditions under which crystal collapse does not occur, the preliminary examination being based on a correlation between presence or absence of the crystal collapse in the silicon single crystal and a position at which an internal stress in the crystal when the silicon single crystal is grown will exceed a prescribed threshold, the position being away from a crystal growth interface; and growing the silicon single crystal in accordance with the growth conditions under which the crystal collapse does not occur, the growth conditions being determined from the preliminary examination. The method can grow a silicon single crystal while crystal collapse is effectively prevented.

Method for growing silicon single crystal

A method for a heat treatment of a silicon single crystal wafer in an oxidizing ambient, including: performing the heat treatment based on a condition determined by a tripartite correlation between a heat treatment temperature during the heat treatment, an oxygen concentration in the silicon single crystal wafer before the heat treatment, and a growth condition of a silicon single crystal from which the silicon single crystal wafer is cut out. This provides a method for a heat treatment of a silicon single crystal wafer which can annihilate void defects or micro oxide precipitate nuclei in a silicon single crystal wafer with low cost, efficiently, and securely by a heat treatment in an oxidizing ambient.

Method for heat treatment of silicon single crystal wafer

The present invention is a method for a heat treatment of a silicon single crystal wafer in an oxidizing ambient, including: performing the heat treatment based on a condition determined by a tripartite correlation between a heat treatment temperature during the heat treatment, an oxygen concentration in the silicon single crystal wafer before the heat treatment, and a void size in the silicon single crystal wafer before the heat treatment. This provides a method for a heat treatment of a silicon single crystal wafer which can annihilate void defects or micro oxide precipitate nuclei in a silicon single crystal wafer with low cost, efficiently, and securely by a heat treatment in an oxidizing ambient.

A method of producing a phosphorus-doped silicon single crystal, including pulling the phosphorus-doped silicon single crystal from a silicon melt doped with phosphorus by Magnetic field applied Czochralski (MCZ) method, wherein the phosphorus is doped such that a phosphorus concentration of the phosphorus-doped silicon single crystal is 2&#xd7;10atoms/cmor more, and a horizontal magnetic field is applied to the silicon melt with a central magnetic field strength of 2,000 gauss or more such that the phosphorus-doped silicon single crystal to be produced has an oxygen concentration of 1.6&#xd7;10atoms/cm(ASTM'79) or more. A method of producing a silicon single crystal that is heavily doped with phosphorus and has an oxygen concentration of 1.6&#xd7;10atoms/cm(ASTM'79) or more.

Method of producing silicon single crystal

A silicon single crystal growing apparatus based on a Czochralski method arranges a graphite crucible inside a graphite heater for heating and a quartz crucible inside the graphite crucible and grows a crystal from a raw material melt filling the quartz crucible, and includes a heater outer heat-insulating member outside the graphite heater, a crucible lower heat-insulating member below the graphite crucible, a crucible upper heat-insulating member above straight bodies of the graphite and quartz crucibles, a crucible outer heat-insulating member outside the straight body of the graphite crucible, a crucible inner heat-insulating member inside the straight bodies of the graphite crucible and the quartz crucible, and a heat shielding member above a liquid surface of the raw material melt, the graphite crucible and the quartz crucible being movable upward and downward in a space enclosed with the crucible upper heat-insulating, crucible outer heat-insulating, and crucible inner heat-insulating members.

Silicon single crystal growing apparatus and method for growing silicon single crystal

A method for evaluating concentration of defect in silicon single crystal substrate, defect being formed by particle beam irradiation in silicon single crystal substrate, including the steps of: measuring a resistivity of silicon single crystal substrate, followed by irradiating silicon single crystal substrate with particle beam, re-measuring resistivity of silicon single crystal substrate after irradiation; determining each carrier concentration in silicon single crystal substrate before and after irradiation on basis of measured results of resistivity before and after particle beam irradiation to calculate rate of change of carrier concentration; and evaluating concentration of VV defect on basis of rate of change of carrier concentration, VV defect being made of a silicon atom vacancy and being formed by particle beam irradiation in silicon single crystal substrate. The method can simply evaluate concentration of VV defect formed in silicon single crystal substrate by particle beam irradiation.

Method for evaluating concentration of defect in silicon single crystal substrate

The present invention provides a method for manufacturing a silicon single crystal wafer, wherein, under a growth condition that V/G&#x2267;1.05&#xd7;(V/G)crt is achieved where V is a growth rate in growth of the silicon single crystal ingot, G is a temperature gradient near a crystal growth interface, and (V/G)crt is a value of V/G when a dominant point defect changes from a vacancy to interstitial Si, a silicon single crystal ingot having oxygen concentration of 7&#xd7;10atoms/cm(ASTM'79) or less is grown, and a silicon single crystal wafer which includes a region where the vacancy is dominant and in which FPDs are not detected by preferential etching is manufactured from the grown silicon single crystal ingot. As a result, there is provided the method that enables manufacturing a low-oxygen concentration silicon single crystal wafer that can be preferably used for a power device with good productivity at a low cost.

Method for manufacturing a defect-controlled low-oxygen concentration silicon single crystal wafer

A method for manufacturing an epitaxial wafer for manufacture of an image pickup device, wherein, before the growth of the epitaxial layer, a thickness X of a region where oxygen concentration in the epitaxial layer becomes 4&#xd7;10atoms/cmor more after the manufacture of the image pickup device is calculated and, in the growth of the epitaxial layer, the epitaxial layer is grown with a thickness such that a thickness of a region where the oxygen concentration in the epitaxial layer is less than 4&#xd7;10atoms/cmafter the manufacture of the image pickup device is 6 &#x3bc;m or more in addition to the thickness X. As a result, it is possible to provide the epitaxial wafer in which an adverse effect of an impurity such as oxygen in the silicon wafer is not exerted on an image pickup device forming portion of the epitaxial layer and a manufacturing method thereof.

Epitaxial wafer and manufacturing method thereof

Methods for producing a silicon wafer from a defect-free silicon single crystal grown by a Czochralski (CZ) method are provided. The methods comprise: preparing a silicon wafer obtained by slicing the defect-free silicon single crystal and subjected to mirror-polishing; then performing a heat treatment step of subjecting the mirror-polished silicon wafer to heat treatment at a temperature of 500&#xb0; C. or higher but 600&#xb0; C. or lower for 4 hours or more but 6 hours or less; and performing a repolishing step of repolishing the silicon wafer after the heat treatment step such that a polishing amount becomes 1.5 &#x3bc;m or more. Therefore, it is an object to provide a method by which a silicon wafer can be produced at a high yield, the silicon wafer in which Light Point Defects (LPDs) are reduced to a minimum, the silicon wafer with a low failure-incidence rate in an inspection step and a shipment stage.

Silicon wafer and method for producing the same

A method for measuring a distance between a lower end surface of a heat insulating member and a surface of a raw material melt with a reference reflector provided at a lower end of the heat insulating member which is located above the surface of the raw material melt when a silicon single crystal is pulled up by a Czochralski method while a magnetic field is applied to the raw material melt in a crucible is disclosed. The method comprises the steps of contacting a projection made of quartz, silicon or carbon with the surface of the raw material melt, the projection being longer that the reference reflector and having a length corresponding to an initial distance; electrically detecting the contact between the projection and the melt surface, and observing an initial location of a mirror image of the reference reflector by a camera when the distance between the lower end surface of the heat insulating member and the surface of the raw material melt has been adjusted so as to be the initial distance, the mirror image being reflected on the surface of the raw material melt; and while pulling the silicon single crystal, measuring a travel distance of the mirror image from the initial location by the camera and calculating the distance between the lower end surface of the heat insulating member and the surface of the raw material melt from the initial travel distance of the mirror image.

Method for measuring distance between lower end surface of heat insulating member and surface of raw material melt and method for controlling thereof

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.

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Nishigo-mura, Japan

Ryoji Hoshi