Abstract: The present invention relates to a nitride semiconductor substrate such as gallium nitride substrate and a method for manufacturing the same. The present invention forms a plurality of trenches on a lower surface of a base substrate that are configured to absorb or reduce stresses applied larger when growing a nitride semiconductor film on the base substrate from a central portion of the base substrate towards a peripheral portion. That is, the present invention forms the trenches on the lower surface of the base substrate such that pitches get smaller or widths or depths get larger from the central portion of the base substrate towards the peripheral portion.

Abstract: A method of manufacturing a nitride semiconductor device is disclosed. The method includes forming a gallium nitride (GaN) epitaxial layer on a first support substrate, forming a second support substrate on the GaN epitaxial layer, forming a passivation layer on a surface of the other region except for the first support substrate, etching the first support substrate by using the passivation layer as a mask, and removing the passivation layer and thereby exposing the second support substrate and the GaN epitaxial layer.

Abstract: A method for manufacturing a gallium nitride (GaN) wafer is provided. In the method for manufacturing the GaN wafer according to an embodiment, an etch stop layer is formed on a substrate, and a first GaN layer is formed on the etch stop layer. A portion of the first GaN layer is etched with a silane gas, and a second GaN layer is formed on the etched first GaN layer. A third GaN layer is formed on the second GaN layer.

Abstract: Disclosed are a semiconductor device, a light emitting device, and a method of manufacturing the same. The semiconductor device includes a substrate, a plurality of rods aligned on the substrate, a metal layer disposed on the substrate between the rods, and a semiconductor layer disposed on and between the rods. Electrical and optical characteristics of the semiconductor device are improved due to the metal layer.

Abstract: Disclosed are a semiconductor device, a light emitting device and a method for manufacturing the same. The semiconductor device includes a substrate, a plurality of rods disposed on the substrate, a plurality of particles disposed between the rods and on the substrate, and a first semiconductor layer disposed on the rods. The method for manufacturing the semiconductor device includes preparing a substrate, disposing a plurality of first particles on the substrate, and forming a plurality of rods by etching a portion of the substrate by using the first particles as an etch mask. The semiconductor device effectively reflects in an upward direction light by the above particles, so that light efficiency is improved. The rods are easily formed by using the first particles.

Abstract: The present invention relates to a nitride semiconductor substrate such as gallium nitride substrate and a method for manufacturing the same. The present invention forms a plurality of trenches on a lower surface of a base substrate that are configured to absorb or reduce stresses applied larger when growing a nitride semiconductor film on the base substrate from a central portion of the base substrate towards a peripheral portion. That is, the present invention forms the trenches on the lower surface of the base substrate such that pitches get smaller or widths or depths get larger from the central portion of the base substrate towards the peripheral portion.

Abstract: A method of manufacturing a nitride semiconductor device is disclosed. The method includes forming a gallium nitride (GaN) epitaxial layer on a first support substrate, forming a second support substrate on the GaN epitaxial layer, forming a passivation layer on a surface of the other region except for the first support substrate, etching the first support substrate by using the passivation layer as a mask, and removing the passivation layer and thereby exposing the second support substrate and the GaN epitaxial layer.

Abstract: The present invention relates to a compound semiconductor substrate and a method for manufacturing the same. The present invention provides the manufacturing method which coats spherical balls on a substrate, forms a metal layer between the spherical balls, removes the spherical balls to form openings, and grows a compound semiconductor layer from the openings. According to the present invention, the manufacturing method can be simplified and grow a high quality compound semiconductor layer rapidly, simply and inexpensively, as compared with a conventional ELO (Epitaxial Lateral Overgrowth) method or a method for forming a compound semiconductor layer on a metal layer. And, the metal layer serves as one electrode of a light emitting device and a light reflecting film to provide a light emitting device having reduced power consumption and high light emitting efficiency.

Abstract: The present invention relates to a nitride semiconductor substrate such as gallium nitride substrate and a method for manufacturing the same. The present invention forms a plurality of trenches on a lower surface of a base substrate that are configured to absorb or reduce stresses on the base substrate that become larger from a central portion of the base substrate towards a peripheral portion when growing a nitride semiconductor film. That is, the present invention forms the trenches on the lower surface of the base substrate such that pitches get smaller or widths or depths get larger from the central portion of the base substrate towards the peripheral portion.

Abstract: Disclosed is a method for formation of a thermal bather coating on a gas turbine during operation thereof, which includes addition of an organic compound containing silicon to a fuel under a first condition in order to form a base layer on the surface of a part coming into contact with a combustion gas of the fuel in the gas turbine during operation thereof, as well as addition of the organic compound containing silicon to the fuel under a second condition in order to form a porous layer having more pores than the base layer above the base layer.

Abstract: Provided is a method for preparing a compound semiconductor substrate. The method includes coating a plurality of spherical balls on a substrate, growing a compound semiconductor epitaxial layer on the substrate coated with the spherical balls while allowing voids to be formed under the spherical balls, and cooling the substrate on which the compound semiconductor epitaxial layer is grown so that the substrate and the compound semiconductor epitaxial layer are self-separated along the voids. The spherical ball treatment can reduce dislocation generations. In addition, because the substrate and the compound semiconductor epitaxial layer are separated through the self-separation, there is no need for laser lift-off process.

Abstract: Provided is a method for preparing a compound semiconductor substrate. The method includes coating a plurality of spherical balls on a substrate, growing a compound semiconductor epitaxial layer on the substrate coated with the spherical balls while allowing voids to be formed under the spherical balls, and cooling the substrate on which the compound semiconductor epitaxial layer is grown so that the substrate and the compound semiconductor epitaxial layer are self-separated along the voids. The spherical ball treatment can reduce dislocation generations. In addition, because the substrate and the compound semiconductor epitaxial layer are separated through the self-separation, there is no need for laser lift-off process.

Abstract: The present invention relates to a method for manufacturing a gallium nitride single crystalline substrate, including (a) growing a gallium nitride film on a flat base substrate made of a material having a smaller coefficient of thermal expansion than gallium nitride and cooling the gallium nitride film to bend convex upwards the base substrate and the gallium nitride film and create cracks in the gallium nitride film; (b) growing a gallium nitride single crystalline layer on the crack-created gallium nitride film located on the convex upward base substrate; and (c) cooling a resultant product having the grown gallium nitride single crystalline layer to make the convex upward resultant product flat or bend convex downwards the convex upward resultant product and at the same time to self-split the base substrate and the gallium nitride single crystalline layer from each other at the crack-created gallium nitride film interposed therebetween.

Abstract: Provided is a method for preparing a substrate for growing gallium nitride and a gallium nitride substrate. The method includes performing thermal cleaning on a surface of a silicon substrate, forming a silicon nitride (Si3N4) micro-mask on the surface of the silicon substrate in an in situ manner, and growing a gallium nitride layer through epitaxial lateral overgrowth (ELO) using an opening in the micro-mask. According to the method, by improving the typical ELO, it is possible to simplify the method for preparing the substrate for growing gallium nitride and the gallium nitride substrate and reduce process cost.

Abstract: The present invention relates to a method for manufacturing a gallium nitride single crystalline substrate, including (a) growing a gallium nitride film on a flat base substrate made of a material having a smaller coefficient of thermal expansion than gallium nitride and cooling the gallium nitride film to bend convex upwards the base substrate and the gallium nitride film and create cracks in the gallium nitride film; (b) growing a gallium nitride single crystalline layer on the crack-created gallium nitride film located on the convex upward base substrate; and (c) cooling a resultant product having the grown gallium nitride single crystalline layer to make the convex upward resultant product flat or bend convex downwards the convex upward resultant product and at the same time to self-split the base substrate and the gallium nitride single crystalline layer from each other at the crack-created gallium nitride film interposed therebetween.

Abstract: Provided is a method for preparing a compound semiconductor substrate. The method includes coating a plurality of spherical balls on a substrate, growing a compound semiconductor epitaxial layer on the substrate coated with the spherical balls while allowing voids to be formed under the spherical balls, and cooling the substrate on which the compound semiconductor epitaxial layer is grown so that the substrate and the compound semiconductor epitaxial layer are self-separated along the voids. The spherical ball treatment can reduce dislocation generations. In addition, because the substrate and the compound semiconductor epitaxial layer are separated through the self-separation, there is no need for laser lift-off process.

Abstract: There is provided a windmill-shaped loop antenna including: a dielectric substrate; a first radiation unit disposed on a top surface of the dielectric substrate and including a metal pattern having loop pieces; a second radiation unit disposed at a bottom surface of the dielectric substrate and including a metal pattern having loop pieces arranged not to face the loop pieces of the first radiation unit; and a plurality of identical transmission line from a center of the top and bottom surfaces of the dielectric substrate to the first and second radiation units, which form windmill-shaped metal pattern with the first and second radiation unit.

Abstract: Provided is a method for preparing a substrate for growing gallium nitride and a gallium nitride substrate. The method includes performing thermal cleaning on a surface of a silicon substrate, forming a silicon nitride (Si3N4) micro-mask on the surface of the silicon substrate in an in situ manner, and growing a gallium nitride layer through epitaxial lateral overgrowth (ELO) using an opening in the micro-mask. According to the method, by improving the typical ELO, it is possible to simplify the method for preparing the substrate for growing gallium nitride and the gallium nitride substrate and reduce process cost.

Abstract: The present invention relates to a nitride semiconductor substrate such as gallium nitride substrate and a method for manufacturing the same. The present invention forms a plurality of trenches on a lower surface of a base substrate that are configured to absorb or reduce stresses applied larger when growing a nitride semiconductor film on the base substrate from a central portion of the base substrate towards a peripheral portion. That is, the present invention forms the trenches on the lower surface of the base substrate such that pitches get smaller or widths or depths get larger from the central portion of the base substrate towards the peripheral portion.

Abstract: The present invention relates to a compound semiconductor substrate and a method for manufacturing the same. The present invention provides the manufacturing method which coats spherical balls on a substrate, forms a metal layer between the spherical balls, removes the spherical balls to form openings, and grows a compound semiconductor layer from the openings. According to the present invention, the manufacturing method can be simplified and grow a high quality compound semiconductor layer rapidly, simply and inexpensively, as compared with a conventional ELO (Epitaxial Lateral Overgrowth) method or a method for forming a compound semiconductor layer on a metal layer. And, the metal layer serves as one electrode of a light emitting device and a light reflecting film to provide a light emitting device having reduced power consumption and high light emitting efficiency.