Abstract: Provided are an optical coupler, which can improve miniaturization and integration, and an active optical module comprising the same. The optical coupler comprises a hollow optical block having a through hole formed to pass an optical fiber therethrough. The hollow optical block comprises at least one incidence plane, at least one internal reflection plane, and at least one tapering region. The incidence plane is disposed at the bottom of the hollow optical block, which is parallel to the through hole, to incident-transmit light. The internal reflection plane is disposed at the top of the hollow optical block, which is opposite to the incidence plane, to reflect the light, which is received from the incidence plane, into the hollow optical block. The tapering region is configured to concentrate the light on the optical fiber in the through hole. The tapering region is formed such that the outer diameter of the hollow optical block decreases away from the internal reflection plane and the incidence plane.

Abstract: Provided are a waveguide structure and an arrayed waveguide grating structure. The arrayed waveguide grating structure includes an input star coupler, an output star coupler, and a plurality of arrayed waveguides optically connecting the input star coupler and the output star coupler. Each of the arrayed waveguides includes at least one section having a high confinement factor and at least two sections having a relatively low confinement factor. The sections of the arrayed waveguides having a high confinement factor have the same structure.

Abstract: A non-volatile memory device includes a feedback circuit and a precharge switching transistor. The feedback circuit generates a feedback signal based on a voltage level of a bitline during a precharge operation. The precharge switching transistor, in response to the feedback signal, controls a precharge current for precharging the bitline. The speed of the precharge operation may be increased and/or mismatch of the bias signals in precharging a plurality of bitlines may be reduced.

Abstract: Provided are a superluminescent diode with a high optical power and a broad wavelength band, and a method of fabricating the same. The superluminescent diode includes: at least one high optical confinement factor (HOCF) region; and at least one low optical confinement factor (LOCF) region having a lower optical confinement factor than the HOCF region. The method includes obtaining a difference of optical confinement factors in the HOCF region and the LOCF region through a selective area growth method, the selective area growth method using a deposition thicknesses difference of thin layers according to a width difference of openings that expose a substrate.

Abstract: Provided is a photonics device including at least two arrayed waveguide grating structures. Each of the arrayed waveguide grating structures of the photonics device includes an input star coupler, an output star coupler, and a plurality of arrayed waveguides optically connecting the input star coupler to the output star coupler. Each of the arrayed waveguides includes at least one first section having a high confinement factor and at least two second sections having a low confinement factor. The first sections of the arrayed waveguides have the same 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 hybrid laser diode. The hybrid laser diode includes: a silicon layer constituting a slab waveguide; and a compound semiconductor layer disposed on the silicon layer to constitute a channel waveguide.

Abstract: Provided is a mask pattern for selective area growth of a semiconductor layer and a selective area growth method for a semiconductor layer for independently controlling a growth rate and a strain of the semiconductor layer. The selective area growth method includes: forming a plurality of pairs of first mask patterns, the first mask patterns in each pair including a first open area therebetween, the first open area having a width that is wider than a distance causing overgrowth of the semiconductor layer, the pairs of the first mask patterns repeatedly arranged with a period P therebetween; wherein controlling a growth rate and a strain of the semiconductor layer formed on the first open area by adjusting the period P.

Abstract: A nonvolatile memory system is operated by performing a program loop on each of a plurality of memory cells, each program loop comprising at least one program-verify operation and selectively pre-charging bit lines associated with each of the plurality of memory cells during the at least one program-verify operation.

Abstract: A flash memory device controls a common source line voltage and performs a program verify method. A plurality of memory cells is connected between a bit line and the common source line. A data input/output circuit is connected to the bit line and is configured to store data to be programmed in a selected memory cell of the plurality of memory cells. The data input/output circuit maintains data to be programmed within the data input/output circuit during a program verify operation, and decreases noise in the common source line by selectively precharging the bit line based on the data to be programmed.

Abstract: Provided are a waveguide structure and an arrayed waveguide grating structure. The arrayed waveguide grating structure includes an input star coupler, an output star coupler, and a plurality of arrayed waveguides optically connecting the input star coupler and the output star coupler. Each of the arrayed waveguides includes at least one section having a high confinement factor and at least two sections having a relatively low confinement factor. The sections of the arrayed waveguides having a high confinement factor have the same structure.

Abstract: The present invention relates to ethylene vinyl acetate based polymer foams with low density and superior injection molding characteristics, a preparation method thereof and a material for medical and health-care use using the same, more particularly to ethylene vinyl acetate based polymer foams with low density prepared by blending, masticating, pelletizing and foaming a matrix resin comprising ethylene vinyl acetate (EVA) resin and ethylene methyl acrylate (EMA) resin under specific condition, which has low density and superior injection molding characteristics and improved biocompatibility to human body, making them a useful environment-friendly material and particularly applicable to medical or health-care use, a preparation method thereof and a material for medical and health-care use using the same.

Abstract: Provided is a photonics device. The photonics device includes: a substrate including a star coupler region and a transition region; a lower core layer formed on the substrate; and upper core patterns formed on the substrate to define a waveguide. The upper core patterns are disposed on the lower core layer at the transition region, so that the transition region has a multi-layered core structure.

Abstract: Provided are a superluminescent diode with a high optical power and a broad wavelength band, and a method of fabricating the same. The superluminescent diode includes: at least one high optical confinement factor (HOCF) region; and at least one low optical confinement factor (LOCF) region having a lower optical confinement factor than the HOCF region. The method includes obtaining a difference of optical confinement factors in the HOCF region and the LOCF region through a selective area growth method, the selective area growth method using a deposition thicknesses difference of thin layers according to a width difference of openings that expose a substrate.

Abstract: Provided are a hybrid laser diode for single mode operation, and a method for manufacturing the hybrid laser diode. The hybrid laser diode includes a silicon layer, an active pattern disposed on the silicon layer, and a bonding layer disposed between the silicon layer and the active pattern. Here, the bonding layer includes diffraction patterns constituting a Bragg grating.

Abstract: Provided is a hybrid laser diode. The hybrid laser diode includes: a silicon layer constituting a slab waveguide; and a compound semiconductor layer disposed on the silicon layer to constitute a channel waveguide.

Abstract: Provided is a bi-directional optical module including: a transmission optical element including an SOA (semiconductor optical amplifier) aligned on an optical axis of an LD (laser diode) formed on a substrate; and a reception optical element comprising a PD (photodiode) including a light receiving surface perpendicular to the optical axis of the LD of the transmission optical element.

Abstract: A system for accessing a node of a private network includes an assigning portion for assigning external port values to respective network nodes based on information collected from the network nodes of the private network, and storing the assigned external port values; an exchanging portion for exchanging the external port values of the respective network nodes of private networks; and an address converting portion for converting the external port values into corresponding private IP addresses and internal port values when a network node of one private network accesses another network node of another private network by using the external port values of another network node of another private network. Accordingly, a network node of a private network without a global IP address becomes accessible.

Abstract: Provided is a semiconductor laser including a substrate etched into a mesa structure, an active layer, clad layers, a current blocking layer, an etch-stop, an ohmic contact layer, and electrodes, and a method for manufacturing the same, whereby it is possible to improve a ratio of light output to input current by blocking a leakage current flowing outside an active waveguide in a BH laser.

Abstract: A semiconductor optical device with a differential grating formed by a holography method and a method for manufacturing the same are provided. The provided semiconductor optical device includes an n-type InP substrate, a stack structure on the InP substrate having a waveguide and active layers, a first grating formed under the stack structure and on the InP substrate, and a second grating formed on the stack structure. The provided method for manufacturing the semiconductor optical device forms a first grating on the n-type InP substrate and under the active layer, and forms a second grating on the active layer. The first and second gratings are formed by the holography method.