Abstract: Provided is an electro-optic device. Sine the electro-optic device includes a plurality of first conductive type semiconductor layers and a plurality of depletion layers formed by a third semiconductor disposed between the plurality of first conductive type semiconductor layers, an electro-optic device optimized for a high speed and low power consumption can be provided.

Abstract: Provided is an optical device having a strained buried channel area. The optical device includes: a semiconductor substrate of a first conductive type; a gate insulating layer formed on the semiconductor substrate; a gate of a second conductive type opposite to the first conductive type, formed on the gate insulating layer; a high density dopant diffusion area formed in the semiconductor substrate under the gate and doped with a first conductive type dopant having a higher density than the semiconductor substrate; a strained buried channel area formed of a semiconductor material having a different lattice parameter from a material of which the semiconductor substrate is formed and extending between the gate insulating layer and the semiconductor substrate to contact the high density dopant diffusion area; and a semiconductor cap layer formed between the gate insulating layer and the strained buried channel area.

Abstract: Provided is an optical device having an edge effect with improved phase shift and propagation loss of light without decreasing the dynamic characteristics of the optical device. The optical device includes a first semiconductor layer which is doped with a first type of conductive impurities, and has a recessed groove in an upper portion thereof; a gate insulating layer covering the groove and a portion of the first semiconductor layer; and a second semiconductor layer which covers an upper surface of the gate insulating layer and is doped with a second type of conductive impurities opposite to the first type of conductive impurities.

Abstract: Provided is a monolithic integrated composite device including: a silicon substrate which is partitioned into a silicon integrated circuit forming region and a silicon optical device forming region; a buried oxide layer which is formed locally in the silicon substrate of the silicon optical device forming region and isolates unit devices of the silicon optical device forming region; an overlay layer formed locally on the buried oxide layer; a silicon optical device formed in the silicon optical device forming region using the silicon overlay layer; a silicon integrated circuit formed in the silicon integrated circuit forming region of the silicon substrate; and wiring connecting the silicon integrated circuit and the silicon optical device or connecting the silicon optical devices or connecting the silicon integrated circuits.

Abstract: Provided is an electro-optic modulating device. The electro-optic modulating device includes an optical waveguide with a vertical structure and sidewalls of the vertical structure are used to configure a junction.

Abstract: Provided is a waveguide photodetector that may improve an operation speed and increase or maximize productivity. The waveguide photodetector includes a waveguide layer extending in a first direction, an absorption layer disposed on the waveguide layer, a first electrode disposed on the absorption layer, a second electrode disposed on the waveguide layer, the second electrode being spaced from the first electrode and the absorption layer in a second direction crossing the first direction, and at least one bridge electrically connecting the absorption layer to the second electrode.

Abstract: An electro-optic device is provided. The electro-optic device includes a junction layer disposed between a first conductivity type semiconductor layer and a second conductivity type semiconductor layer to which a reverse vias voltage is applied. The first conductivity type semiconductor layer and the second conductivity type semiconductor layer have an about 2 to 4-time doping concentration difference therebetween, thus making it possible to provide the electro-optic device optimized for high speed, low power consumption and high integration.

Abstract: Provided is an optical coupler. The optical coupler includes a lower cladding layer on a substrate, a core layer on the lower cladding layer, the core layer comprising a diffraction grating coupler and an optical waveguide, and an upper cladding layer on the core layer. The upper cladding layer has a thickness of about one quarter of a wavelength of an optical signal passing through the core layer divided by a refractive index of the first upper cladding layer. Thus, Fresnel reflection may be minimized, and also, it may prevent a Fabry-Perot interferometer from occurring.

Abstract: Provided is an optical device, which includes a substrate, a first cladding disposed on the substrate, a first optical waveguide extended in a first direction on the first cladding, and having a first refractive index, a side grating formed in at least one side of the first optical waveguide, a second optical waveguide filling a space of the side grating, extended in a second direction across the first direction on the first cladding, and having a second refractive index, and a second cladding disposed on the second optical waveguide, and having a third refractive index, wherein the first refractive index is greater than the second refractive index, and the second refractive index is greater than the third refractive index.

Abstract: Provided are an optical device and a method of fabricating the same. The optical device includes: a substrate; and a ring resonator on the substrate. The ring resonator includes: a cladding layer including a lower cladding layer and an upper cladding layer on the substrate; a core including a plurality of rings between the lower cladding layer and the upper cladding layer; and an embeded layer interposed between the core and the cladding layer and having a refractive index less than that of the core and more than that of the cladding layer.

Abstract: Provided is a 2-terminal semiconductor device that uses an abrupt MIT semiconductor material layer. The 2-terminal semiconductor device includes a first electrode layer, an abrupt MIT semiconductor organic or inorganic material layer having an energy gap less than 2 eV and holes in a hole level disposed on the first electrode layer, and a second electrode layer disposed on the abrupt MIT semiconductor organic or inorganic material layer. An abrupt MIT is generated in the abrupt MIT semiconductor material layer by a field applied between the first electrode layer and the second electrode layer.

Abstract: Provided is a silicon array waveguide grating (AWG) device comprising a silicon array waveguide in which a plurality of optical waveguides formed of a lower cladding layer, a silicon core, and an upper cladding layer are arranged, wherein the variation of the refractive index of the silicon core is positive, and the upper cladding layer is formed of polymer, the variation of refractive index of which according to temperature is negative, which is opposite to the silicon core, and the cross-section of the silicon core varies between different areas to adjust the variation of the effective refractive index of the optical waveguide according to temperature.

Abstract: An interband resonant tunneling intersubband transition laser is disclosed, and includes a semiconductor substrate, and a first cladding layer, an active region structure layer and a second cladding layer formed on the semiconductor substrate. The active region structure layer includes quantum well layers and quantum barrier layers that are alternately stacked and have a broken energy bandgap. Thus, the interband resonant tunneling intersubband transition laser operates in a cascade mode in which an intersubband radiative transition and interband tunneling of carriers consecutively and repetitively occur in the active region structure layer, and thus can achieve a high output from a simple, compact structure.

Abstract: Provided is an optical device, which includes a substrate, a first cladding disposed on the substrate, a first optical waveguide extended in a first direction on the first cladding, and having a first refractive index, a side grating formed in at least one side of the first optical waveguide, a second optical waveguide filling a space of the side grating, extended in a second direction across the first direction on the first cladding, and having a second refractive index, and a second cladding disposed on the second optical waveguide, and having a third refractive index, wherein the first refractive index is greater than the second refractive index, and the second refractive index is greater than the third refractive index.

Abstract: An absorption modulator is provided. The absorption modulator includes a substrate, an insulation layer disposed on the substrate, and a waveguide having a P-I-N diode structure on the insulation layer. Absorptance of an intrinsic region in the P-I-N diode structure is varied when modulating light inputted to the waveguide. The absorption modulator obtains the improved characteristics, such as high speed, low power consumption, and small size, because it greatly reduces the cross-sectional area of the P-I-N diode structure.

Abstract: Provided is a resonator of a hybrid laser diode. The resonator includes: a substrate including a semiconductor layer where a hybrid waveguide, a multi-mode waveguide, and a single mode waveguide are connected in series; a compound semiconductor waveguide, provided on the hybrid waveguide of the semiconductor layer, having a tapered coupling structure at one end of the compound semiconductor waveguide, the tapered coupling structure overlapping the multi-mode waveguide partially; and a reflection part provided on one end of the single mode waveguide. The multi-mode waveguide has a narrower width than the hybrid waveguide and the single mode waveguide has a narrower width than the multi-mode waveguide.

Abstract: Provided is a 2-terminal semiconductor device that uses an abrupt MIT semiconductor material layer. The 2-terminal semiconductor device includes a first electrode layer, an abrupt MIT semiconductor organic or inorganic material layer having an energy gap less than 2eV and holes in a hole level disposed on the first electrode layer, and a second electrode layer disposed on the abrupt MIT semiconductor organic or inorganic material layer. An abrupt MIT is generated in the abrupt MIT semiconductor material layer by a field applied between the first electrode layer and the second electrode layer.

Abstract: Provided are a method of fabricating a semiconductor device unconstrained by optical limit and an apparatus of fabricating the semiconductor device. The method includes: forming an etch target layer on a substrate; forming a hard mask layer on the etch target layer; forming first mask patterns on the hard mask layer; forming first spacers on sidewalls of the first mask patterns; forming hard mask patterns having an opening by using the first mask patterns and the first spacers as a mask to etch the hard mask layer; aligning second mask patterns on the hard mask patterns to fill the opening; forming second spacers on sidewalls of the second mask patterns; forming fine mask patterns by using the second mask patterns and the second spacers as a mask to etch the hard mask patterns; and forming fine patterns by using the fine mask patterns as a mask to etch the etch target layer.

Abstract: Provided are semiconductor integrated circuits including a grating coupler for optical communication and methods of forming the same. The semiconductor integrated circuit includes: a cladding layer disposed on a semiconductor substrate; a grating coupler including an optical waveguide on the cladding layer and a grating on the optical waveguide; and at least one reflector formed in the cladding layer below the grating.

Abstract: Provided is a photonics device. The photonics device includes a distribution Bragg reflector (DBR), first and second waveguides disposed at both sides of the DBR, first lenses disposed between the DBR and the first waveguides, and second lenses disposed between the DBR and the second waveguides.