Toyota Jidosha Kabushiki Kaisha

Nippon Steel Sumitomo Metal Corporation

Sumitomo Metal Industries, Inc.

Mitsubishi Electric Corporation

Showa Denko K.k.

Nippon Steel & Sumitomo Metal Corporatin

Resonac Corporation

Kazuhiko Kusunoki

Hiroshi Suzuki

Kazuhito Kamei

Hironori Daikoku

Motohisa Kado

Hidemitsu Sakamoto

Nobuyoshi Yashiro

Nobuhiro Okada

Kazuaki Seki

Katsunori Danno

Masayoshi Doi

Koji Moriguchi

Yutaka Kishida

Tomokazu Ishii

Akihiro Yauchi

Kouji Moriguchi

Junichi Koike

Tatsuo Fujimoto

Ryo Hattori

Hiroshi Tsuge

Takayuki Yano

Tomohiro Sato

Shinji Munetoh

Yoichiro Kawai

Shinji Shimosaki

Komomo Tani

Yoshihisa Ueda

Yutaka Itoh

A method for a SiC single crystal that allow prolonged growth to be achieved are provided. A method for producing a SiC single crystal in which a seed crystal substrate held on a seed crystal holding shaft is contacted with a Si&#x2014;C solution having a temperature gradient such that a temperature of the Si&#x2014;C solution decreases from an interior of the Si&#x2014;C solution toward a liquid level of the Si&#x2014;C solution, in a graphite crucible, to grow a SiC single crystal, wherein the method comprises the steps of: electromagnetic stirring of the Si&#x2014;C solution with an induction coil to produce a flow, and heating of a lower part of the graphite crucible with a resistance heater.

SiC single crystal production method and production apparatus

Provided is a SiC single crystal that has a large growth thickness and contains no inclusions. A SiC single crystal grown by a solution process, wherein the total length M of the outer peripheral section formed by the {1-100} faces on the {0001} growth surface of the SiC single crystal, and the length P of the outer periphery of the growth surface of the SiC single crystal, satisfy the relationship M/P&#x2264;0.70, and the length in the growth direction of the SiC single crystal is 2 mm or greater.

SiC single crystal and method for producing same

Provided is a method for producing a SiC single crystal which can suppress generation of SiC polycrystals. The method according to the present embodiment is in accordance with a solution growth method. The method for producing a SiC single crystal according to the present embodiment comprises a power-output increasing step, a contact step, and a growth step. In the power-output increasing step, high-frequency power output of an induction heating device is increased to crystal-growth high-frequency power output. In the contact step, a SiC seed crystal is brought into contact with a Si&#x2014;C solution. The high-frequency power output of the induction heating device in the contact step is more than 80% of the crystal-growth high-frequency power output. The temperature of the Si&#x2014;C solution in the contact step is less than a crystal growth temperature. In the growth step, the SiC single crystal is grown at the crystal growth temperature.

Method for producing SiC single crystal

A production method according an embodiment of the present invention is to produce a SiC single crystal by a solution growth technique, and includes a formation step and a growth step. In the formation step, material of Si&#x2014;C solution contained in a crucible is melted, and a Si&#x2014;C solution is formed. In the growth step, a SiC seed crystal attached to a bottom end of a seed shaft is brought into contact with the Si&#x2014;C solution, and a SiC single crystal is grown on a crystal growth surface of the SiC seed crystal. In the growth step, while a temperature of the Si&#x2014;C solution is being raised, the SiC single crystal is grown. The SiC single crystal production method according to the embodiment facilitates production of a SiC single crystal of a desired polytype.

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

Provided is a method for producing a SiC single crystal having a concave growth surface and containing no inclusions, even when conducting large diameter crystal growth. This is achieved by a method for producing a SiC single crystal in which a seed crystal substrate held on a seed crystal holding shaft is contacted with a Si&#x2014;C solution having a temperature gradient such that the temperature decreases from the interior toward the liquid level, to cause crystal growth of a SiC single crystal, wherein the seed crystal holding shaft has a shaft portion and a seed crystal holding portion at the bottom end of the shaft portion, and the ratio of the diameter Dof the shaft portion to the diameter Dof the seed crystal holding portion (D/D) is no greater than 0.28.

The present invention provides a method of raising the rate of reduction of the dislocation density accompanying growth of an SiC single crystal to counter the increase in the threading screw dislocations formed near the interface of the seed crystal and grown SiC single crystal and thereby produce an SiC single-crystal ingot with a small threading screw dislocation density from the initial stage of growth. The present invention is a method for producing a silicon carbide single-crystal ingot growing a silicon carbide single crystal on a growth face of a seed crystal consisting of a silicon carbide single crystal by a physical vapor transport method so as to produce a silicon carbide single-crystal ingot, the method for producing a silicon carbide single-crystal ingot comprising forming step bunching with heights of steps of 10 &#x3bc;m to 1 mm and spans of terraces of 200 &#x3bc;m to 1 mm on the growth face of the seed crystal and making the silicon carbide single crystal grow on the growth face of the seed crystal by the physical vapor transport method.

Method for producing silicon carbide single-crystal ingot and silicon carbide single-crystal ingot

Provided is a method for producing a SiC single crystal wherein generation of polycrystals can be inhibited even if the temperature of the Si&#x2014;C solution is changed after seed touching. This is achieved by a method for producing a SiC single crystal wherein a SiC seed crystal substrate held on a seed crystal holding shaft is contacted with a Si&#x2014;C solution having a temperature gradient in which the temperature decreases from the interior toward the surface, to grow a SiC single crystal, comprising the steps of: (A) bringing the temperature of the solution to a first temperature, (B) contacting the substrate held on the holding shaft with the solution, (C) bringing the temperature of the solution to a second temperature after the contacting the substrate with the solution, and (D) moving the substrate held on the holding shaft in the vertical direction according to the change in liquid surface height of the solution when the temperature of the solution is brought from the first temperature to the second temperature.

The production method of an SiC single crystal is a production method of an SiC single crystal by a solution growth process. The production method includes a contact step A, a contact step B, and a growth step. In the contact step A, a partial region of the principal surface is brought into contact with a stored Si&#x2014;C solution. In the contact step B, a contact region between the principal surface and the stored Si&#x2014;C solution expands, due to a wetting phenomenon, starting from an initial contact region which is the partial region brought into contact in the contact step A. In the growth step, an SiC single crystal is grown on the principal surface which is in contact with the stored Si&#x2014;C solution.

Production method of SiC single crystal

An apparatus for producing SiC single crystals where the quality of the SiC single crystals is improved, and a production method using such an apparatus are provided. The apparatus for producing SiC single crystals according to an embodiment of the present invention is employed to produce an SiC single crystal by the solution growth method. The production apparatus includes a crucible and a support shaft. The crucible accommodates an Si&#x2014;C solution. The support shaft supports the crucible. The support shaft includes a heat removing portion for removing heat from a bottom portion of the crucible. The heat removing portion includes one of (a) a contact portion having a thermal conductivity not less than that of the bottom portion and contacting at least a portion of the bottom portion and (b) a space adjacent to at least a portion of the contact portion or the bottom portion.

Apparatus for producing SiC single crystals and method of producing SiC single crystals using said production apparatus

A method for producing a SiC single crystal by a solution process is provided, which allows generation of miscellaneous crystals to be reduced. Method for producing a SiC single crystal wherein a crucible has thickness Lu in horizontal direction at same height as liquid level of Si&#x2014;C solution, and thickness Ld in horizontal direction at same height as bottom inner wall, Ld/Lu is 2.00 to 4.21, and thickness in horizontal direction of crucible monotonously increases between Lu and Ld from Lu toward Ld, wall thickness of crucible is 1 mm or greater, bottom thickness Lb in vertical direction of crucible is between 1 mm and 15 mm, bottom outer wall of crucible has flat section with area of 100 mmor greater, depth of Si&#x2014;C solution from bottom inner wall is 30 mm or greater, and method includes heating and electromagnetic stirring Si&#x2014;C solution with high-frequency coil.

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

The purpose of the present invention is to produce a high-quality SiC single crystal with good reproducibility while avoiding the fluctuations in the solution-contacting position of a seed crystal among production operations. A method for producing a SiC single crystal by bringing a SiC seed crystal supported by a supporting bar into contact with a solution that has been heated by high-frequency induction to thereby grow the SiC single crystal, wherein the supporting bar is born down while applying a magnetic field to the solution to thereby bring the SiC seed crystal into contact with the solution, and subsequently the application of the magnetic field is halted to grow the SiC single crystal.

Method for producing a SiC single crystal in the presence of a magnetic field which is applied to a solution

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

Growing community of inventors

Tokyo, Japan

Kazuhiko Kusunoki