Toyota Jidosha Kabushiki Kaisha

Nippon Steel Sumitomo Metal Corporation

Sumitomo Metal Industries, Inc.

Mitsubishi Electric Corporation

Nobuyoshi Yashiro

Hiroshi Suzuki

Kazuhito Kamei

Kazuhiko Kusunoki

Nobuhiro Okada

Hironori Daikoku

Motohisa Kado

Hidemitsu Sakamoto

Koji Moriguchi

Akihiro Yauchi

Kouji Moriguchi

Junichi Koike

Ryo Hattori

Katsunori Danno

Tomokazu Ishii

Yoichiro Kawai

Shinji Shimosaki

Yutaka Itoh

Yoshihisa Ueda

An apparatus () for producing an SiC single crystal is used in the solution growth includes a seed shaft () and a crucible (). The seed shaft () has a lower end surface (S) to which an SiC seed crystal () is to be attached. The crucible () holds an Si&#x2014;C solution (). The seed shaft () includes a cylinder part (A), a bottom part (B), and a low heat conductive member (C). The bottom part (B) is located at the lower end of the cylinder part (A) and has the lower end surface (S). The low heat conductive member (C) is arranged on the upper surface of the bottom part (B) and has a thermal conductivity lower than that of the bottom part (B). This production apparatus can make the temperature within the crystal growth surface of the SiC seed crystal less liable to vary.

Apparatus for producing SiC single crystal and method for producing SiC single crystal

A production apparatus is used for a solution growth method. The production apparatus includes a seed shaft and a crucible. The seed shaft has a lower end surface to which an SiC seed crystal is attached. The crucible contains an SiC solution. The crucible includes a cylindrical portion, a bottom portion, and an inner lid. The bottom portion is disposed at a lower end of the cylindrical portion. The inner lid is disposed in the cylindrical portion. The inner lid has a through hole and is positioned below a liquid surface of the SiC solution when the SiC solution is contained in the crucible.

Apparatus for producing SiC single crystal by solution growth method, and method for producing SiC single crystal by using the production apparatus and crucible used in the production apparatus

An apparatus for producing an SiC single crystal includes a crucible for accommodating an Si&#x2014;C solution and a seed shaft having a lower end surface where an SiC seed crystal () would be attached. The seed shaft includes an inner pipe that extends in a height direction of the crucible and has a first passage. An outer pipe accommodates the inner pipe and constitutes a second passage between itself and the inner pipe and has a bottom portion whose lower end surface covers a lower end opening of the outer pipe. One passage of the first and second passages serves as an introduction passage where coolant gas flows downward, and the other passage serves as a discharge passage where coolant gas flows upward. A region inside the pipe that constitutes the introduction passage is to be overlapped by a region of not less than 60% of the SiC seed crystal.

Production apparatus and production method of SiC single crystal

A region of an SiC solution in the vicinity of an SiC seed crystal is cooled while suppressing the temperature variation in a peripheral region of the SiC solution. An apparatus includes a seed shaft and a crucible for an SiC solution. The seed shaft has a lower end surface for attachment to an SiC seed crystal. The crucible comprises a main body, an intermediate cover, and a top cover. The main body includes a first cylindrical portion and a bottom portion at a lower end portion of the first cylindrical portion. The intermediate cover is within the first cylindrical portion and above the liquid level of the SiC solution in the main body. The intermediate cover has a first through hole for the seed shaft. The top cover is disposed above the intermediate cover and has a second through hole for the seed shaft to pass through.

Production apparatus of SiC single crystal by solution growth method, method for producing SiC single crystal using the production apparatus, and crucible used in the production apparatus

An apparatus for SIC single crystal has an induction heating control unit such that frequency f (Hz) of alternating current to the induction heating unit satisfies Formula (1); D1 (mm) is permeation depth of electromagnetic waves into a crucible side wall by the heating unit, D2 (mm) is permeation depth of electromagnetic waves into a SIC solution, T (mm) is thickness of the crucible side wall of the crucible, and R (mm) is crucible inner radius:(1&#x2212;)&#xd7;2/&#x3e;1.5&#x2003;&#x2003;(1) where, D1 is defined by Formula (2) and D2 by Formula (3):1=503292&#xd7;(1/())&#x2003;&#x2003;(2)2=503292&#xd7;(1/())&#x2003;&#x2003;(3); &#x3c3;c is electric conductivity (S/m) of the sidewall, &#x3c3;s is electric conductivity (S/m) of the SiC solution; &#x3bc;c is relative permeability of the sidewall, and &#x3bc;s is relative permeability of the SIC solution.

Manufacturing apparatus of SiC single crystal and method for manufacturing SiC single crystal

A method for manufacturing an n-type SiC single crystal, enables the suppression of the variation in nitrogen concentration among a plurality of n-type SiC single crystal ingots manufactured. A method includes the steps of: providing a manufacturing apparatus () including a chamber () having an area in which a crucible () is to be disposed; heating the area in which the crucible () is to be disposed and evacuating the gas in the chamber (); filling, after the evacuation, the chamber () with a mixed gas containing a noble gas and nitrogen gas; heating and melting a starting material housed in the crucible () disposed in the area to produce a SiC solution () containing silicon and carbon; and immersing a SiC seed crystal into the SiC solution under the mixed gas atmosphere to grow an n-type SiC single crystal on the SiC seed crystal.

Method for manufacturing N-type SiC single crystal by solution growth using a mixed gas atmosphere

A manufacturing apparatus of a SiC single crystal which can suppress the generation of a polycrystal is provided. A jig () and a crucible () are accommodated in a chamber (). A SiC solution () is housed in the crucible (). The jig () includes a seed shaft () and a cover member (). The seed shaft () can move up and down, and a SiC seed crystal () is attached to the lower surface thereof. The cover member () is attached to the lower end portion of the seed shaft (). The cover member () is a housing which has an opening at its lower end, wherein the lower end portion of the seed shaft () is disposed in the cover member ().

Manufacturing apparatus of SiC single crystal, jig for use in the manufacturing apparatus, and method for manufacturing SiC single crystal

A SiC single crystal wafer on which a good quality epitaxial film by suppressing defects derived from the wafer can be grown has an affected surface layer with a thickness of at most 50 nm and a SiC single crystal portion with an oxygen content of at most 1.0&#xd7;10atoms/cm. This SiC single crystal wafer is manufactured from a high purity SiC bulk single crystal obtained by the solution growth method using raw materials with an oxygen content of at most 100 ppm and a non-oxidizing atmosphere having an oxygen concentration of at most 100 ppm.

SiC single crystal wafer and process for production thereof

A manufacturing method for a SiC single crystal film which allows stable growth of a SiC epitaxial film with a low doping concentration on a substrate with a diameter of at least 2 inches by the LPE method using a SiC solution in solvent of a melt includes an evacuation step in which the interior of a crystal growth furnace is evacuated with heating until the vacuum pressure at the crystal growth temperature is 5&#xd7;10Pa or lower prior to introducing a raw material for the melt into the furnace. Then, a crucible containing a raw material for the melt is introduced into the furnace, a SiC solution is formed, and a SiC epitaxial film is grown on a substrate immersed in the solution.

Method and apparatus for manufacturing a SiC single crystal film

A method capable of stably manufacturing a SiC single crystal in the form of a thin film or a bulk crystal having a low carrier density of at most 5&#xd7;10/cmand preferably less than 1&#xd7;10/cmand which is suitable for use in various devices by liquid phase growth using a SiC solution in which the solvent is a melt of a Si alloy employs a Si alloy having a composition which is expressed by SiCrTiwherein x, y, and z (each in atomic percent) satisfy0.50&#x3c;x&#x3c;0.68, 0.08&#x3c;y&#x3c;0.35, and 0.08&#x3c;z&#x3c;0.35, or &#x2003;&#x2003;(1)0.40&#x3c;x&#x2266;0.50, 0.15&#x3c;y&#x3c;0.40, and 0.15&#x3c;z&#x3c;0.35.&#x2003;&#x2003;(2)x, y, and z preferably satisfy 0.53&#x3c;x&#x3c;0.65, 0.1&#x3c;y&#x3c;0.3, and 0.1&#x3c;z&#x3c;0.3.

Method of manufacturing a silicon carbide single crystal

A SiC single crystal is produced by the solution growth method in which a seed crystal attached to a seed shaft is immersed in a solution of SiC dissolved in a melt of Si or a Si alloy and a SiC single crystal is allowed to grow on the seed crystal by gradually cooling the solution or by providing a temperature gradient therein. To this method, accelerated rotation of a crucible is applied by repeatedly accelerating to a prescribed rotational speed and holding at that speed and decelerating to a lower rotational speed or a 0 rotational speed. The rotational direction of the crucible may be reversed each acceleration. The seed shaft may also be rotated synchronously with the rotation of the crucible in the same or opposite rotational as the crucible. A large, good quality single crystal having no inclusions are produced with a high crystal growth rate.

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Tokyo, Japan

Nobuyoshi Yashiro