Toyota Jidosha Kabushiki Kaisha

Nippon Steel Sumitomo Metal Corporation

Nippon Steel & Sumitomo Metal Corporatin

Motohisa Kado

Hiroshi Suzuki

Kazuhiko Kusunoki

Hironori Daikoku

Kazuhito Kamei

Hidemitsu Sakamoto

Nobuhiro Okada

Nobuyoshi Yashiro

Koji Moriguchi

Kazuaki Seki

Katsunori Danno

Yutaka Kishida

Tomohiro Sato

Hayate Yamano

Tomokazu Ishii

Masayoshi Doi

Toshimasa Hara

Yoichiro Kawai

Kouji Moriguchi

The present disclosure provides a method for producing a semiconductor element that can lower the potential risk of malfunction. The production method of the disclosure is a method for producing a semiconductor element which includes providing a semiconductor element precursor, the precursor having a metal electrode layer formed on the surface of a gallium oxide-based single crystal semiconductor layer and a dopant doped in at least part of an exposed portion on the surface of the gallium oxide-based single crystal semiconductor layer where the metal electrode layer is not layered, and annealing treatment of the semiconductor element precursor whereby the dopant is diffused to a portion of the gallium oxide-based single crystal semiconductor layer that are overlapping with the metal electrode layer in the layering direction, to form a Schottky junction between the gallium oxide-based single crystal semiconductor layer and the metal electrode layer.

Method for producing semiconductor element

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

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.

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 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

A SiC single crystal manufacturing method whereby growing speed improvement required to have high productivity can be achieved, while maintaining flat growth in which uniform single crystal growth can be continued at the time of growing a SiC single crystal using a solution method. In the method, a SiC single crystal is grown in a crucible from a Si solution containing C. The method includes alternately repeating: a high supersaturation degree growing period, in which the growth is promoted by maintaining the supersaturation degree of C in the Si solution higher than an upper limit critical value at which flat growth can be maintained, the supersaturation degree being at a growing interface between the Si solution and a SiC single crystal being grown; and a low supersaturation degree growing period, in which the growth is promoted by maintaining the supersaturation degree lower than the critical value.

SiC single crystal manufacturing method using alternating states of supersaturation

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

Provided is a method for producing an SiC single crystal, which is capable of greatly increasing the growth rate in a solution technique in comparison to conventional methods. A method for producing an SiC single crystal, wherein an SiC single crystal is grown by bringing a seed crystal substrate into contact with an Si&#x2014;C solution that is put in a crucible and has a temperature gradient decreasing from the inside to the liquid level, and wherein the value of depth/inner diameter of the crucible is less than 1.71 and the temperature gradient of the Si&#x2014;C solution from the liquid level to 10 mm below the liquid level is larger than 42&#xb0; C./cm.

Method for producing SiC single crystal

Provided are: a high-quality SiC single crystal ingot that suppresses the generation of inclusions; and a production method for said SiC single crystal ingot. The present invention pertains to a SiC single crystal ingot including a seed crystal substrate and a SiC growth crystal grown using the solution method and using the seed crystal substrate as the origin thereof, the growth crystal having a recessed crystal growth surface and not including inclusions.

SiC single crystal ingot and production method therefor

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 ().

Growing community of inventors

Susono, Japan

Motohisa Kado