Abstract: There is provided a compound semiconductor substrate prepared by forming a point defect in an inside structure thereof by implanting an electrically-neutral impurity with energy of 0.1 to 10 MeV on a surface of the substrate. When the compound semiconductor is undoped, electrical resistance increases to increase insulating properties, and when the compound semiconductor is doped with an n-type dopant, the impurity is implanted and charge concentration of the substrate increases to increase conductive properties. In accordance with the present invention, the various electrical properties needed for the compound semiconductor can be effectively controlled by increasing the insulating properties of the undoped compound semiconductor or by increasing the charge concentration of the n-type compound semiconductor, and the application range to various devices can be expanded.

Abstract: The present invention relates to a freestanding, thick, single crystalline gallium nitride (GaN) film having significantly reduced bending deformation. The inventive GaN film having a crystal tilt angle of C-axis to the <0001> direction per surface distance of 0.0022°/mm exhibits little bending deformation even at a thickness of 1 mm or more, and therefore, is beneficially used as a substrate for a luminescent device.

Abstract: There is provided a compound semiconductor substrate prepared by forming a point defect in an inside structure thereof by implanting an electrically-neutral impurity with energy of 0.1 to 10MeV on a surface of the substrate. When the compound semiconductor is undoped, electrical resistance increases to increase insulating properties, and when the compound semiconductor is doped with an n-type dopant, the impurity is implanted and charge concentration of the substrate increases to increase conductive properties. In accordance with the present invention, the various electrical properties needed for the compound semiconductor can be effectively controlled by increasing the insulating properties of the undoped compound semiconductor or by increasing the charge concentration of the n-type compound semiconductor, and the application range to various devices can be expanded.

Abstract: A method of manufacturing a single crystalline gallium nitride (GaN) thick film by using a hydride gas phase epitaxy (HVPE), more particularly, the method of manufacturing c-plane ({0001}) of a single crystalline GaN thick film by using the HVPE. A GaN film is grown on a substrate by providing a hydrogen chloride (HCl) gas and an ammonia (NH3) gas, thereby obtaining the GaN film on the substrate, and a GaN thick film on the GaN film on the substrate is grown.

Abstract: A nitride semiconductor template having nano-voids at an interface between a substrate having one embossed surface and a nitride semiconductor layer can be rapidly prepared by hydride vapor phase epitaxy (HVPE) growth of the nitride semiconductor layer on the embossed surface of the substrate.