Abstract: A silicon carbide crystal ingot includes first crystal layers and second crystal layers, each being alternately disposed and all containing one of a donor and acceptor, wherein a concentration of the donor or the acceptor that at least one of the second crystal layers has is higher than a concentration of the donor or the acceptor that one of the first crystal layers has, the one of the first crystal layers being in contact with the at least one of the second crystal layers.

Abstract: A method of producing a crystal includes a step of preparing a solution containing carbon and a silicon solvent, and a seed crystal of silicon carbide; a step of contacting a lower face of the seed crystal with the solution; a step of raising a temperature of the solution to a first temperature zone; a step of relatively elevating the seed crystal with respect to the solution in a state where a temperature of the solution is being lowered from the first temperature zone to a second temperature zone; a step of raising a temperature of the solution from the second temperature zone to the first temperature zone; and a step of relatively elevating the seed crystal with respect to the solution in a state where a temperature of the solution is being lowered from the first temperature zone to the second temperature zone.

Abstract: A crucible 1 according to an embodiment of the present invention is a crucible 1 which is used in a solution growth method for growing a crystal of silicon carbide on a lower surface 3B of a seed crystal 3 from a solution 2, by accommodating the solution 2 of silicon containing carbon in the crucible 1, by allowing the lower surface 3B of the seed crystal 3 to contact with the solution 2 from above, and by pulling the seed crystal 3 upward. The crucible is made of carbon and includes a solution adjustment member 4 which is fixed to an inner wall surface 1A so as to be positioned between a bottom surface 1B and a liquid surface of the solution 2 when the crucible 1 is used and which includes a through hole 4a overlapped with an inner side of the seed crystal 3 disposed above.

Abstract: A holder according to one embodiment is a holder which is used in a solution growth method of growing a crystal on a lower surface of a seed crystal by contacting the lower surface of the seed crystal with a solution of silicon including carbon in a crucible having an opening on an upper end thereof. The holder includes: a holding member which holds the seed crystal on a lower surface; the seed crystal which is held on the lower surface of the holding member, has an upper surface larger than the lower surface, and is made of silicon carbide; and a suppressing member which is fixed to a side surface of the holding member, continues from the side surface to outside further outward than an outer circumference of the seed crystal in plan view, and suppresses upward movement of vapor from the solution.

Abstract: A seed crystal holder according to the present invention for growing a crystal by a solution method, and that includes a seed crystal made of silicon carbide; a holding member above the seed crystal; a bonding agent configured to fix the seed crystal and the holding member; and a sheet member made of carbon which is interposed in the bonding agent in a thickness direction, and which has an outer periphery smaller than an outer periphery of the seed crystal in a plan view.

Abstract: A method for producing a crystal, according to the present invention, where the lower surface of a seed crystal which is rotatably arranged and made of silicon carbide is brought into contact with a solution of silicon solvent containing carbon in a crucible which is rotatably arranged and the seed crystal is pulled up and a crystal of silicon carbide is grown from the solution on the lower surface of the seed crystal, comprising the steps of bringing the lower surface of the seed crystal into contact with the solution in a contact step, rotating the seed crystal in a seed crystal rotation step, rotating the crucible in a crucible rotation step, and stopping rotation of the crucible, while the seed crystal is rotated in the state in which the lower surface of the seed crystal is in contact with the solution, in a deceleration step.

Abstract: A light emitting element includes an optical semiconductor layer (2) obtained by sequentially laminating a first semiconductor layer (2a), a light emitting layer (2b), and a second semiconductor layer (2c); a first electrode layer (3) that is electrically connected to the first semiconductor layer (2a); and a second electrode layer (7) that is electrically connected to the second semiconductor layer (2c). The second electrode layer (7) includes a conductive reflecting layer (4) positioned on the second semiconductor layer (2c), and a conductive layer (5) having a plurality of through holes (6) that are positioned on the conductive reflecting layer (4) and penetrate therethrough in a thickness direction thereof.

Abstract: A light emitting element includes an optical semiconductor layer (2) obtained by sequentially laminating a first semiconductor layer (2a), a light emitting layer (2b), and a second semiconductor layer (2c); a first electrode layer (3) that is electrically connected to the first semiconductor layer (2a); and a second electrode layer (7) that is electrically connected to the second semiconductor layer (2c). The second electrode layer (7) includes a conductive reflecting layer (4) positioned on the second semiconductor layer (2c), and a conductive layer (5) having a plurality of through holes (6) that are positioned on the conductive reflecting layer (4) and penetrate therethrough in a thickness direction thereof.

Abstract: A light emitting element comprises a semiconductor layer (8) in which a first conductive-type gallium nitride-based compound semiconductor layer (8a), a light emitting layer (8b) composed of a gallium nitride-based compound semiconductor, and a second conductive-type gallium nitride-based compound semiconductor layer (8c) are laminated; and a porous transparent conductive layer (20) that has a porosity becoming higher in a thickness direction thereof from a side of the semiconductor layer (8) or a transparent conductive layer (20) that has a refractive index becoming lower in a thickness direction thereof from a side of the semiconductor layer (8), the transparent conductive layer (20) being formed on a main surface of the semiconductor layer (8). By this structure, a light emitting element that enables to dramatically improve light extraction efficiency can be obtained.

Abstract: A method and an apparatus for melting a metallic material in the form of a pile of elongate metal ingots, wherein the ingot pile are pre-heated in a horizontal pre-heating chamber while the pile is moved from its one end to the other end, and the pre-heated pile at the other end is pushed into a melting chamber which communicates with the pre-heating chamber and extends vertically downwardly from the other end of the pre-heating chamber, whereby the pile is turned sideways before falling down into the melting chamber, with a result of collapse of the pile into the individual metal ingots in the melting chamber.