A lithium metal negative electrode for an electrochemical cell for a secondary lithium metal battery includes a polycrystalline metal substrate having a major facing surface with a defined crystallographic texture. An epitaxial lithium metal layer is formed on the major facing surface of the polycrystalline metal substrate. The epitaxial lithium metal layer exhibits a predominant crystal orientation. The predominant crystal orientation of the epitaxial lithium metal layer is derived from the defined crystallographic texture of the major facing surface of the polycrystalline metal substrate.

It is produced a crystal of a nitride of a group 13 element in a melt including the group 13 element and a flux including at least an alkali metal under atmosphere comprising a nitrogen-containing gas. An amount of carbon is made 0.005 to 0.018 atomic percent, provided that 100 atomic percent is assigned to a total amount of said flux, said group 13 element and carbon in said melt.

It is produced a crystal of a nitride of a group 13 element in a melt including the group 13 element and a flux including at least an alkali metal under atmosphere comprising a nitrogen-containing gas. An amount of carbon is made 0.005 to 0.018 atomic percent, provided that 100 atomic percent is assigned to a total amount of said flux, said group 13 element and carbon in said melt.

Provided is a method that allows growing a single crystal of silicon carbide on an off-substrate of silicon carbide while suppressing surface roughening. The method for producing a crystal of silicon carbide includes rotating a seed crystal of silicon carbide while bringing the seed crystal into contact with a starting material solution containing silicon and carbon. A crystal growth surface of the seed crystal has an off-angle, and the position of a rotation center of the seed crystal lies downstream of the central position of the seed crystal in a step flow direction that is a formation direction of the off-angle.

Provided is a method that allows growing a single crystal of silicon carbide on an off-substrate of silicon carbide while suppressing surface roughening. The method for producing a crystal of silicon carbide includes rotating a seed crystal of silicon carbide while bringing the seed crystal into contact with a starting material solution containing silicon and carbon. A crystal growth surface of the seed crystal has an off-angle, and the position of a rotation center of the seed crystal lies downstream of the central position of the seed crystal in a step flow direction that is a formation direction of the off-angle.

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 SiC 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 SiC 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.

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 SiC 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 SiC 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.

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 SiC solution contained in a crucible is melted, and a SiC 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 SiC 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 SiC 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.

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 SiC solution contained in a crucible is melted, and a SiC 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 SiC 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 SiC 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.

According to one embodiment, a treatment method may include making a byproduct come into contact with a treatment solution, wherein the byproduct is a solid or liquid byproduct formed by polymerizing components contained in an exhaust gas discharged by synthesizing a silicon-containing material using a gas which includes silicon and halogen. The treatment solution may include at least one of an inorganic base or an organic base, and is basic.