Thin freestanding nitride veneers can be used for the fabrication of semiconductor devices. These veneers are typically less than 100 microns thick. The use of thin veneers also eliminates the need for subsequent wafer thinning for improved thermal performance and 3D packaging.

A Group III nitride substrate contains a base material part of a Group III nitride having a front surface and a back surface, the front surface of the base material part and the back surface of the base material part having different Mg concentrations from each other.

A Group III nitride substrate contains a base material part of a Group III nitride having a front surface and a back surface, the front surface of the base material part and the back surface of the base material part having different Mg concentrations from each other.

A crystal layer of a nitride of a group 13 element includes a pair of main surfaces. The crystal layer includes high carrier concentration regions having a carrier concentration of 1×10.sup.18/cm.sup.3 or more and low carrier concentration regions having a carrier concentration of 9×10.sup.17/cm.sup.3 or less, viewed in a cross section perpendicular to the main surfaces of the crystal layer. Each of the low carrier concentration regions is extended in an elongated shape. The low carrier concentration regions include association parts. The low carrier concentration regions are extended continuously between the pair of the main surfaces.

A crystal layer of a nitride of a group 13 element includes a pair of main surfaces. The crystal layer includes high carrier concentration regions having a carrier concentration of 1×10.sup.18/cm.sup.3 or more and low carrier concentration regions having a carrier concentration of 9×10.sup.17/cm.sup.3 or less, viewed in a cross section perpendicular to the main surfaces of the crystal layer. Each of the low carrier concentration regions is extended in an elongated shape. The low carrier concentration regions include association parts. The low carrier concentration regions are extended continuously between the pair of the main surfaces.

A method of forming a semiconductor structure is provided. The method includes etching a trench in a template layer over a substrate, forming a seed structure over a bottom surface of the trench, forming a dielectric cap over the seed structure, and growing a single crystal semiconductor structure within the trench using a vapor liquid solid epitaxy growth process. The single crystal semiconductor structure is grown from a liquid-solid interface between the seed structure and the bottom surface of the trench.

A method of forming a semiconductor structure is provided. The method includes etching a trench in a template layer over a substrate, forming a seed structure over a bottom surface of the trench, forming a dielectric cap over the seed structure, and growing a single crystal semiconductor structure within the trench using a vapor liquid solid epitaxy growth process. The single crystal semiconductor structure is grown from a liquid-solid interface between the seed structure and the bottom surface of the trench.

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.

A method for producing a Group III nitride crystal includes: preparing a protective layer on a region except for an epitaxial growth surface of an RAMO.sub.4 substrate containing a single crystal represented by the general formula RAMO.sub.4 (wherein R represents one or a plurality of a trivaient element selected from a group of elements including: Sc, In, Y, and a lanthanoid element, A represents one or a plurality of a trivalent element selected from a group of elements including: Fe(III), Ga, and Al, and M represents one or a plurality of a divalent element selected from a group of elements including: Mg, Mn, Fe(II), Co, Cu, Zn, and Cd); and forming a Group III nitride crystal on the epitaxial growth surface of the RAMO.sub.4 substrate by a flux method.