Abstract: Provided are an optical coupling device and a method for manufacturing the same. The optical coupling device includes a first waveguide including a first forward tapered part, a second waveguide disposed on the first waveguide and including a first reverse tapered part in a direction opposite to the first forward tapered part, and an interlayer waveguide disposed between the first and second waveguides and having a thickness corresponding to a distance between the first forward tapered part and the first reverse tapered part.

Abstract: Disclosed are an optical input/output device and an opto-electronic system including the same. The device includes a bulk silicon substrate, at least one vertical-input light detection element monolithically integrated on a portion of the bulk silicon substrate, and at least one vertical-output light source element monolithically integrated on another portion of the bulk silicon substrate adjacent to the vertical-input light detection element. The vertical-output light source element includes a III-V compound semiconductor light source active layer combined with the bulk silicon substrate by a wafer bonding method.

Abstract: Provided is a laser device according to an embodiment of the inventive concept. The laser device includes: a semiconductor substrate; a germanium single crystal layer on the semiconductor substrate; and a pumping light source disposed on the germanium single crystal layer and configured to emit light toward the germanium single crystal layer, wherein the germanium single crystal layer receives the light to thereby output laser.

Abstract: Provided are an optical coupling device and a method for manufacturing the same. The optical coupling device includes a first waveguide including a first forward tapered part, a second waveguide disposed on the first waveguide and including a first reverse tapered part in a direction opposite to the first forward tapered part, and an interlayer waveguide disposed between the first and second waveguides and having a thickness corresponding to a distance between the first forward tapered part and the first reverse tapered part.

Abstract: Provided is a thermo-optic optical switch including an input waveguide configured to receive an optical signal, an output waveguide configured to output the optical signal, branch waveguides branching from the input waveguide to be connected to the output waveguide, and heater electrodes disposed on the branch waveguides and configured to heat the branch waveguides, wherein the branch waveguides includes first and second phase shifters having first and second thermo-optic coefficients of opposite signs.

Abstract: Disclosed are an optical input/output device and an opto-electronic system including the same. The device includes a bulk silicon substrate, at least one vertical-input light detection element monolithically integrated on a portion of the bulk silicon substrate, and at least one vertical-output light source element monolithically integrated on another portion of the bulk silicon substrate adjacent to the vertical-input light detection element. The vertical-output light source element includes a III-V compound semiconductor light source active layer combined with the bulk silicon substrate by a wafer bonding method.

Abstract: A wavelength division multiplexer is disclosed. The wavelength division multiplexer may include an input waveguide, in which a plurality of Bragg gratings for separating multiplexed optical signals into respective optical signals are provided, and a plurality of output waveguides connected to the input waveguide and configured to receive the optical signals separated by the plurality of Bragg gratings. The plurality of Bragg gratings may include a first Bragg grating including first protrusions each having a first width, and a second Bragg grating including second protrusions each having a second width larger than the first width. Each of the first and second protrusions may include a curved side surface, to which a corresponding one of the optical signals is incident.

Abstract: Provided is a laser device according to an embodiment of the inventive concept. The laser device includes: a semiconductor substrate; a germanium single crystal layer on the semiconductor substrate; and a pumping light source disposed on the germanium single crystal layer and configured to emit light toward the germanium single crystal layer, wherein the germanium single crystal layer receives the light to thereby output laser.

Abstract: Provided is an optical switch including a substrate, a first optical waveguide disposed on the substrate and having a conductive portion disposed on one surface thereof, and a second optical waveguide disposed on the substrate being spaced apart from the first optical waveguide and having an electrode portion disposed on one surface thereof. The electrode portion and the conductive portion face each other. The electrode portion controls an optical field between the first optical waveguide and the second optical waveguide.

Abstract: Provided is an optical coupler including a substrate, a buffer layer on the substrate, a ridge waveguide having a first side surface and a second side surface opposed to the first side surface, and a first waveguide disposed adjacent to the second side surface. The first waveguide includes a first body part and a first connecting part extending from one end of the first body part to be inserted in the ridge waveguide. The first connecting part has a width decreasing in the direction away from the second side surface, and the ridge waveguide includes an extension part extending under an upper surface of the buffer layer.

Abstract: Provided is an optical switch including a substrate, a first optical waveguide disposed on the substrate and having a conductive portion disposed on one surface thereof, and a second optical waveguide disposed on the substrate being spaced apart from the first optical waveguide and having an electrode portion disposed on one surface thereof. The electrode portion and the conductive portion face each other. The electrode portion controls an optical field between the first optical waveguide and the second optical waveguide.

Abstract: Provided is a thermo-optic optical switch including an input waveguide configured to receive an optical signal, an output waveguide configured to output the optical signal, branch waveguides branching from the input waveguide to be connected to the output waveguide, and heater electrodes disposed on the branch waveguides and configured to heat the branch waveguides, wherein the branch waveguides includes first and second phase shifters having first and second thermo-optic coefficients of opposite signs.

Abstract: A wavelength division multiplexer is disclosed. The wavelength division multiplexer may include an input waveguide, in which a plurality of Bragg gratings for separating multiplexed optical signals into respective optical signals are provided, and a plurality of output waveguides connected to the input waveguide and configured to receive the optical signals separated by the plurality of Bragg gratings. The plurality of Bragg gratings may include a first Bragg grating including first protrusions each having a first width, and a second Bragg grating including second protrusions each having a second width larger than the first width. Each of the first and second protrusions may include a curved side surface, to which a corresponding one of the optical signals is incident.

Abstract: Provided is an optical coupler including a substrate, a buffer layer on the substrate, a ridge waveguide having a first side surface and a second side surface opposed to the first side surface, and a first waveguide disposed adjacent to the second side surface. The first waveguide includes a first body part and a first connecting part extending from one end of the first body part to be inserted in the ridge waveguide. The first connecting part has a width decreasing in the direction away from the second side surface, and the ridge waveguide includes an extension part extending under an upper surface of the buffer layer.

Abstract: An optical device module includes a substrate, an interlayer insulating layer on the substrate, an optical waveguide on the interlayer insulating layer, an optical device on the optical waveguide, and a prism disposed between the optical device and the optical waveguide. The prism has a refractive index greater than a refractive index of the optical waveguide.

Abstract: Provided are a semiconductor device and a method for manufacturing the same. The semiconductor device according to an embodiment of the inventive concept includes a first semiconductor chip having a recess portion in one surface thereof; a first adhesion pattern filled within the recess portion of the first semiconductor chip; and a second semiconductor chip disposed on the first adhesion pattern. The second semiconductor chip may represent improved heat dissipation characteristics.

Abstract: Provided is a laser device according to an embodiment of the inventive concept. The laser device includes: a semiconductor substrate; a germanium single crystal layer on the semiconductor substrate; and a pumping light source disposed on the germanium single crystal layer and configured to emit light toward the germanium single crystal layer, wherein the germanium single crystal layer receives the light to thereby output laser.

Abstract: Disclosed are an optical input/output device and an opto-electronic system including the same. The device includes a bulk silicon substrate, at least one vertical-input light detection element monolithically integrated on a portion of the bulk silicon substrate, and at least one vertical-output light source element monolithically integrated on another portion of the bulk silicon substrate adjacent to the vertical-input light detection element. The vertical-output light source element includes a III-V compound semiconductor light source active layer combined with the bulk silicon substrate by a wafer bonding method.

Abstract: Disclosed are an optical input/output device and an opto-electronic system including the same. The device includes a bulk silicon substrate, at least one vertical-input light detection element monolithically integrated on a portion of the bulk silicon substrate, and at least one vertical-output light source element monolithically integrated on another portion of the bulk silicon substrate adjacent to the vertical-input light detection element. The vertical-output light source element includes a III-V compound semiconductor light source active layer combined with the bulk silicon substrate by a wafer bonding method.

Abstract: Provided is a photodetector including a substrate, a first doped region on the substrate, a second doped region having a ring structure, wherein the second doped region is provided in the substrate, surrounds the first doped region and is horizontally spaced apart from a side of the first doped region, an optical absorption layer on the first doped region, a contact layer on the optical absorption layer, a first electrode on the contact layer, and a second electrode on the second doped region.