Sumco Corporation

Sumitomo Mitsubishi Silicon Corporation

Wataru Sugimura

Toshiaki Ono

Masataka Hourai

Ryusuke Yokoyama

Hideki Sakamoto

Naoki Matsushima

Toshiyuki Fujiwara

Mitsuaki Hayashi

Ken Nakajima

Akihiko Endo

Shigeru Umeno

Takayuki Kubo

Shinsuke Sadamitsu

Tadami Tanaka

Akira Higuchi

Ippei Shimozaki

Masanori Akatsuka

A convection pattern estimation method of a silicon melt includes: applying a horizontal magnetic field of 0.2 tesla or more to a silicon melt in a rotating quartz crucible with use of a pair of magnetic bodies disposed across the quartz crucible; before a seed crystal is dipped into the silicon melt to which the horizontal magnetic field is applied; measuring temperatures at a first and second measurement points positioned on a first imaginary line that passes through a center of a surface of the silicon melt and is not in parallel with a central magnetic field line of the horizontal magnetic field as viewed vertically from above; and estimating a direction of a convection flow in a plane in the silicon melt orthogonal to the direction in which the horizontal magnetic field is applied on a basis of the measured temperatures of the first and second measurement points.

Method of estimating convection pattern of silicon melt, method of estimating oxygen concentration of silicon single crystal, method of manufacturing silicon single crystal, and raising device of silicon single crystal

A convection pattern control method includes: heating a silicon melt in a quartz crucible using a heating portion; and applying a horizontal magnetic field to the silicon melt in the quartz crucible being rotated. In the heating of the silicon, the silicon melt is heated with the heating portion whose heating capacity differs on both sides across an imaginary line passing through a center axis of the quartz crucible and being in parallel to a central magnetic field line of the horizontal magnetic field when the quartz crucible is viewed from vertically above. In the applying of the horizontal magnetic field, the horizontal magnetic field of 0.2 tesla or more is applied to fix a direction of a convection flow in a single direction in a plane orthogonal to an application direction of the horizontal magnetic field in the silicon melt.

Method for controlling convection pattern of silicon melt, method for producing silicon single crystals, and device for pulling silicon single crystals

A method of manufacturing monocrystalline silicon by flowing inert gas in a chamber, applying horizontal magnetic field to a silicon melt in a quartz crucible, and pulling up monocrystalline silicon includes: forming a flow distribution of a flow of the inert gas flowing between a lower end of a heat shield and a surface of the silicon melt in the quartz crucible to be plane asymmetric with respect to a plane defined by a crystal pull-up axis of the pull-up device and an application direction of the horizontal magnetic field and rotationally asymmetric with respect to the crystal pull-up axis: maintaining the formed plane asymmetric and rotationally asymmetric flow distribution in a magnetic-field-free state until a silicon material in the quartz crucible is completely melted; and applying the horizontal magnetic field to the completely melted silicon material and starting pulling up the monocrystalline silicon.

Silicon monocrystal manufacturing method and silicon monocrystal pulling device

A method of controlling a convection pattern of a silicon melt includes applying a horizontal magnetic field having an intensity of 0.2 tesla or more to the silicon melt in a rotating quartz crucible to fix a direction of a convection flow in a plane orthogonal to an application direction of the horizontal magnetic field in the silicon melt, the horizontal magnetic field being applied so that a central magnetic field line passes through a point horizontally offset from a center axis of the quartz crucible by 10 mm or more.

Method of controlling convection patterns of silicon melt and method of manufacturing silicon single crystal

A method of controlling a convection pattern of a silicon melt includes: acquiring a temperature at a first measurement point not overlapping a rotation center of a quartz crucible on a surface of the silicon melt, the quartz crucible rotating in a magnetic-field-free state; determining that the temperature at the first measurement point periodically changes; and fixing a direction of a convection flow to a single direction in a plane orthogonal with an application direction of a horizontal magnetic field in the silicon melt by starting a drive of a magnetic-field applying portion to apply the horizontal magnetic field to the silicon melt when a temperature change at the first measurement point reaches a predetermined state, and subsequently raising the intensity to 0.2 tesla or more.

Method for controlling convection pattern of silicon melt and method for producing monocrystalline silicon

Provided is a method of producing a high resistance n-type silicon single crystal ingot with small tolerance margin on resistivity in the crystal growth direction, which is suitably used in a power device. In the method of producing a silicon single crystal ingot using Sb or As as an n-type dopant, while a silicon single crystal ingot is pulled up, the amount of the n-type dopant being evaporated from a silicon melt per unit solidification ratio is kept within a target evaporation amount range per unit solidification ratio by controlling one or more pulling condition values including at least one of the pressure in a chamber, the flow volume of Ar gas, and a gap between a guide portion and the silicon melt.

Method of producing silicon single crystal ingot and silicon single crystal ingot

A silicon single crystal manufacturing method by a Czochralski method pulls up a silicon single crystal from a silicon melt in a quartz crucible while applying a magnetic field to the silicon melt. During a pull-up process of the silicon single crystal, the surface temperature of the silicon melt is continuously measured, and crystal growth conditions are changed based on a result of frequency analysis of the surface temperature.

Method and apparatus for manufacturing silicon single crystal

An apparatus for manufacturing a silicon single crystal is provided. The apparatus comprises a chamber (), a quarts crucible () provided in the chamber so as to be rotatable and movable upward and downward and store a silicon melt, a first heater () for melting a silicon raw material stored in the crucible, and a pulling mechanism () provided in the chamber so as to be rotatable and movable upward and downward. The pulling mechanism has a lower end to which a seed crystal (S) is attached. The seed crystal is to be dipped in the silicon melt in the crucible and pulled upward for growing a silicon single crystal by a Czochralski method. The apparatus further comprises a melt supplying mechanism () for supplying an additional silicon melt to the silicon melt in the crucible from external of the chamber. The melt supplying mechanism includes a melt inlet pipe () disposed at an inclination angle &#x3b8;1 of 50&#xb0; to 80&#xb0; with respect to the melt surface of the silicon melt and a melt generating mechanism () for supplying the additional silicon melt (M) to an opening part () of a base end of the melt inlet pipe. The melt inlet pipe has a tip end provided with an opening part (). The opening part of the tip end has an annular surface inclined at an angle &#x3b8;with respect to a direction orthogonal to the axis of the melt inlet pipe. The annular surface has a vertically lower side () and a vertically upper side (). The vertically lower side is located nearer to the tip end in the axis direction than the vertically upper side.

Apparatus for manufacturing silicon single crystal and melt inlet pipe of the same

A method for manufacturing a silicon wafer includes a step of annealing a silicon wafer which is sliced from a silicon single crystal ingot, thereby forming a DZ layer in a first surface and in a second surface of the silicon wafer and a step of removing either a portion of the DZ layer in the first surface or a portion of the DZ layer in the second surface.

Silicon wafer and method for manufacturing the same

In this silicon single crystal wafer for IGBT, COP defects and dislocation clusters are eliminated from the entire region in the radial direction of the crystal, the interstitial oxygen concentration is 8.5&#xd7;10atoms/cmor less, and variation in resistivity within the wafer surface is 5% or less. This method for manufacturing a silicon single crystal wafer for IGBT includes introducing a hydrogen atom-containing substance into an atmospheric gas at a hydrogen gas equivalent partial pressure of 40 to 400 Pa, and growing a single crystal having an interstitial oxygen concentration of 8.5&#xd7;10atoms/cmor less at a silicon single crystal pulling speed enabling pulling of a silicon single crystal free of grown-in defects. The pulled silicon single crystal is irradiated with neutrons so as to dope with phosphorous; or an n-type dopant is added to the silicon melt; or phosphorous is added to the silicon melt so that the phosphorous concentration in the silicon single crystal is 2.9&#xd7;10to 2.9&#xd7;10atoms/cmand a p-type dopant having a segregation coefficient smaller than that of the phosphorous is added to the silicon melt so that the concentration in the silicon single crystals is 1&#xd7;10to 1&#xd7;10atoms/cmcorresponding to the segregation coefficient thereof.

Silicon single crystal wafer for IGBT and method for manufacturing silicon single crystal wafer for IGBT

A process for producing an SOI substrate includes the steps of forming an oxide film on at least the front surface of a first silicon substrate, implanting hydrogen ion from the surface of the first silicon substrate and thereby forming an ion implantation area in the inside of the first silicon substrate, laminating a second silicon substrate onto the first silicon substrate via the oxide film and thereby forming a laminated body of the first silicon substrate and the second silicon substrate bonded with each other, and heating the laminated body at a predetermined temperature and thereby separating the first silicon substrate at the ion implantation area and thereby obtaining an SOI substrate wherein a thin film SOI layer is formed on the second silicon substrate via the oxide film. The first silicon substrate is formed by slicing an ingot free of an agglomerate of vacancy type point defects and an agglomerate of interstitial silicon type point defects grown by a CZ method in an inorganic atmosphere including hydrogen. The layer transferred wafer separated from the SOI layer is used again as the first silicon substrate.

Process for producing SOI substrate and process for regeneration of layer transferred wafer in the production

When growing a silicon single crystal free of grown-in defects based on the CZ method, the crystal is pulled out at a critical pulling rate at which a ring-shaped OSF occurrence region vanishes in a center portion of the crystal by using a hot zone structure in which a temperature gradient Gc in a center portion of the crystal is equal to or greater than a temperature gradient Ge in a peripheral portion of the crystal, while supplying an inert gas including hydrogen to an interior of a pulling furnace. The critical pulling rate at which the ring-shaped OSF occurrence region vanishes in the center portion of the crystal is increased, and single crystals free of grown-in defects in which dislocation clusters and COPs can be grown by pulling at a pulling rate higher than that of the prior art.

Silicon wafer, SOI substrate, method for growing silicon single crystal, method for manufacturing silicon wafer, and method for manufacturing SOI substrate

There is obtained a silicon wafer which has a large diameter, where no slip generated therein in a wide range of a density of oxygen precipitates even though a heat treatment such as SLA or FLA is applied thereto, and which has high strength. First, by inputting as input parameters combinations of a plurality of types of oxygen concentrations and thermal histories set for manufacture of a silicon wafer, a Fokker-Planck equation is solved to calculate each of a diagonal length L and a density D of oxygen precipitates in the wafer after a heat treatment step to form the oxygen precipitates () and immediately before a heat treatment step of a device manufacturing process is calculated. Then, a maximum heat stress S acting in a tangent line direction of an outer peripheral portion of the wafer in the heat treatment step of the device manufacturing process is calculated based on a heat treatment furnace structure and a heat treatment temperature used in the heat treatment step of the device manufacturing process, and then an oxygen concentration or the like satisfying the following Expression (1) is determined:12000&#xd7;&#x2003;&#x2003;(1).

Method for manufacturing silicon wafer method

A silicon single crystal is grown by the CZ method. A silicon melt from which the crystal is grown is added with dopant such that the crystal has a resistivity of 0.025 to 0.08 &#x3a9;cm. As well as the dopant, carbon is added to the silicon melt. The crystal is pulled in a hydrogen-bearing inert atmosphere.

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Tokyo, Japan

Wataru Sugimura