Abstract: A laser annealing apparatus includes a laser oscillating structure, an oscillator, a beam expanding telescope, a first power meter, and a second power meter. The laser oscillating structure emits a first laser beam of a first wavelength and first beam cross-section to a substrate in a chamber including an optical window. The oscillator emits a second laser beam, of a second wavelength different from the first wavelength, to the substrate. The beam expanding telescope is on an optical path for the second laser beam and expands the second laser beam to a second beam cross-section. The first and second power meters measure energy of the second laser beam and a third laser beam, generated as the second laser beam is reflected by the substrate. The first beam cross-section and the second beam cross-section may be equal.

Abstract: A laser annealing apparatus includes a laser oscillating structure, an oscillator, a beam expanding telescope, a first power meter, and a second power meter. The laser oscillating structure emits a first laser beam of a first wavelength and first beam cross-section to a substrate in a chamber including an optical window. The oscillator emits a second laser beam, of a second wavelength different from the first wavelength, to the substrate. The beam expanding telescope is on an optical path for the second laser beam and expands the second laser beam to a second beam cross-section. The first and second power meters measure energy of the second laser beam and a third laser beam, generated as the second laser beam is reflected by the substrate. The first beam cross-section and the second beam cross-section may be equal.

Abstract: An IC device includes a polycrystalline silicon thin film interposed between a first level semiconductor circuit and a second level semiconductor circuit which are formed on a substrate and disposed to vertically overlap each other. The polycrystalline silicon thin film includes at least one silicon single crystal. The at least one silicon single crystal includes a flat horizontal portion, which provides an active region of the second level semiconductor device, and a pin-shaped protruding portion protruding from the flat horizontal portion toward the first level semiconductor device.

Abstract: An IC device includes a polycrystalline silicon thin film interposed between a first level semiconductor circuit and a second level semiconductor circuit which are formed on a substrate and disposed to vertically overlap each other. The polycrystalline silicon thin film includes at least one silicon single crystal. The at least one silicon single crystal includes a flat horizontal portion, which provides an active region of the second level semiconductor device, and a pin-shaped protruding portion protruding from the flat horizontal portion toward the first level semiconductor device.

Abstract: An IC device includes a polycrystalline silicon thin film interposed between a first level semiconductor circuit and a second level semiconductor circuit which are formed on a substrate and disposed to vertically overlap each other. The polycrystalline silicon thin film includes at least one silicon single crystal. The at least one silicon single crystal includes a flat horizontal portion, which provides an active region of the second level semiconductor device, and a pin-shaped protruding portion protruding from the flat horizontal portion toward the first level semiconductor device.

Abstract: An IC device includes a polycrystalline silicon thin film interposed between a first level semiconductor circuit and a second level semiconductor circuit which are formed on a substrate and disposed to vertically overlap each other. The polycrystalline silicon thin film includes at least one silicon single crystal. The at least one silicon single crystal includes a flat horizontal portion, which provides an active region of the second level semiconductor device, and a pin-shaped protruding portion protruding from the flat horizontal portion toward the first level semiconductor device.

Abstract: A method of forming an epitaxial layer includes forming a plurality of first insulation patterns in a substrate, the plurality of first insulation patterns spaced apart from each other, forming first epitaxial patterns on the plurality of first insulation patterns, forming second insulation patterns between the plurality of first insulation patterns to contact the plurality of first insulation patterns, and forming second epitaxial patterns on the second insulation patterns and between the first epitaxial patterns to contact the first epitaxial patterns, the first epitaxial patterns and the second epitaxial patterns forming a single epitaxial layer.

Abstract: A method of fabricating a semiconductor device, the method including forming a trench on a substrate; forming an insulating layer pattern within the trench; depositing an amorphous material on the substrate and the insulating layer pattern; planarizing the amorphous material; removing a portion of the amorphous material, the removed portion of the amorphous material being on an area of the substrate where the trench has been formed; crystallizing remaining portions of the amorphous material into a single crystal material; and planarizing the single crystal material.

Abstract: An optical input/output (I/O) device is provided. The device includes a substrate including an upper trench; a waveguide disposed within the upper trench of the substrate; a photodetector disposed within the upper trench of the substrate and comprising a first end surface optically connected to an end surface of the waveguide; and a light-transmitting insulating layer interposed between the end surface of the waveguide and the first end surface of the photodetector.

Abstract: A method of forming an epitaxial layer includes forming a plurality of first insulation patterns in a substrate, the plurality of first insulation patterns spaced apart from each other, forming first epitaxial patterns on the plurality of first insulation patterns, forming second insulation patterns between the plurality of first insulation patterns to contact the plurality of first insulation patterns, and forming second epitaxial patterns on the second insulation patterns and between the first epitaxial patterns to contact the first epitaxial patterns, the first epitaxial patterns and the second epitaxial patterns forming a single epitaxial layer.

Abstract: An optical input/output (I/O) device is provided. The device includes a substrate including an upper trench; a waveguide disposed within the upper trench of the substrate; a photodetector disposed within the upper trench of the substrate and comprising a first end surface optically connected to an end surface of the waveguide; and a light-transmitting insulating layer interposed between the end surface of the waveguide and the first end surface of the photodetector.