Electronics and Telecommunications Research Institute

Won Seok Han

O Kyun Kwon

Hyun Woo Song

Young Gu Ju

O-Kyun Kwon

Sang Hee Park

Namje Kim

Duk Jun Kim

Jong Hee Kim

Jae Heon Shin

Shinmo An

Miran Park

Yongsoon Baek

Dong-Young Kim

Jong-Hoi Kim

Jung-Ho Song

Young-Ho Ko

Yong-Duck Chung

Tae-Soo Kim

Hyun Soo Kim

Kisoo Kim

Bong Je Park

Young-Tak Han

Jang Uk Shin

Hong-Seok Seo

Sung Bock Kim

Byung-Seok Choi

Joong-Seon Choe

Ki Soo Kim

Dae Kon Oh

Jonghyurk Park

Jae-Sik Sim

Mi Ran Park

Kap-Joong Kim

Byueng Su Yoo

Dong Hyo Lee

Ho Sung Kim

Dae-Hyung Cho

Byung-seok Choi

Jung Rae Ro

Disclosed are a Mach-Zehnder interferometric optical modulator and a method for manufacturing the same. The modulator includes first and second lower clad layers, a core layer, an upper clad layer, a waveguide, and electrodes. The waveguide may include an input waveguide, a waveguide divider, branch waveguides, and a waveguide combiner. Each of the branch waveguides includes first and second connection regions connected to the waveguide combiner and the waveguide divider, respectively, and a phase shift region having a cross-section of a reverse mesa structure that has an upper width that is the same as widths of the first and second connection regions and a lower width that is smaller than the widths of the first and second connection regions.

Mach-zehnder interferometric optical modulator with shallow ridge waveguide structure and method for manufacturing the same

Disclosed are a quantum light source and an optical communication apparatus including the same. The quantum light source device includes a vertical reflection layer disposed on a substrate, a lower electrode layer disposed on the vertical reflection layer, a horizontal reflection layer disposed on the lower electrode layer, a quantum light source disposed in the horizontal reflection layer, and an upper electrode layer disposed on the horizontal reflection layer.

Quantum light source device and optical communication apparatus including the same

Provided is a waveguide photodetector including a semiconductor substrate, a first optical waveguide and a second optical waveguide, which are sequentially laminated on the semiconductor substrate, in which each of the first optical waveguide and the second optical waveguide includes a first portion and a second portion, and the first portion extends from the second portion in a first direction parallel to a top surface of the semiconductor substrate, a refractive index matching layer disposed on the second portion of the second optical waveguide, a clad layer disposed on the refractive index matching layer, and an absorber disposed between the refractive index matching layer and the clad layer. Here, the second optical waveguide has a first conductive-type, the clad layer has a second conductive-type opposite to the first conductive-type, and the refractive index matching layer includes a first semiconductor layer that is an intrinsic semiconductor layer.

Waveguide photodetector

Provided is a quarter-wavelength shifted distributed feedback laser diode. The laser diode includes a substrate having a laser diode section and a phase adjustment section, a waveguide layer on the substrate, a clad layer on the waveguide layer, a grating disposed in the clad layer in the laser diode section, an anti-reflection coating disposed on one side walls, of the substrate, the waveguide layer, and the clad layer, adjacent to the laser diode section, and a high reflection coating disposed on the other side walls, of the substrate, the waveguide layer, and the clad layer, adjacent to the phase adjustment section.

High-output power quarter-wavelength shifted distributed feedback laser diode

Provided is a tunable semiconductor laser including an active gain region in which an optical signal is generated according to a modulation signal, a mode control region in which a resonant mode is controlled according to a mode control signal, and a signal chirp of the optical signal is compensated according to a first compensation signal determined based on the modulation signal, and a distributed Bragg reflector (DBR) region in which an oscillation wavelength of the optical signal is determined based on a wavelength selection signal for the optical signal, a second compensation signal for compensating for a thermal chirp of the optical signal on a basis of the modulation signal, and a heater signal provided to a heater electrode.

Tunable semiconductor laser and operation method thereof

Provided is an optical detection device including a first ohmic contact layer of a first conductivity type, a second ohmic contact layer of a second conductivity type, and first and second mesa structures stacked between the first and second ohmic contact layers. The first mesa structure includes an electric field buffer layer; and a diffusion layer formed in the electric field buffer layer. The second mesa structure includes a light absorbing layer and a grading layer on the light absorbing layer.

Optical detection device

An optical waveguide structure includes a substrate and a core structure disposed on the substrate. The substrate includes a first waveguide region, a second waveguide region, and a transition region between the first waveguide region and the second waveguide region. The core structure includes first core segments arranged in a first direction and a second direction crossing the first direction on the transition region. The core structure includes second core segments arranged in the first direction and the second direction on the second waveguide region. The first direction and the second direction are parallel to a top surface of the substrate.

Optical waveguide structure

An optical signal generating apparatus according to an embodiment of the inventive concept includes a first optical intensity modulator for modulating a first optical signal to generate a 2-level (where N is a positive integer) second optical signal in the form of a binary signal, a first optical amplifier for amplifying the second optical signal to generate a third optical signal, and a second optical intensity modulator for modulating the third optical signal to generate a 2-level fourth optical signal in the form of a binary signal. The optical signal generating apparatus according to an embodiment of the inventive concept may generate a low-cost, high-quality optical signal by using an optical device to generate a multi-level optical signal. Additionally, the optical signal generating apparatus according to an embodiment of the inventive concept may generate a multi-level optical signal by sequentially performing optical modulation and optical amplification operations.

Optical signal generating apparatus and operating method thereof

A method of manufacturing a solar cell includes forming a buffer layer between an optical absorption layer and a window electrode layer. Forming the buffer layer includes depositing a metal material on the optical absorption layer, supplying a non-metal material on the optical absorption layer, supplying a gas material including oxygen atoms on the optical absorption layer, and reacting the metal material with the non-metal material. The gas material reacts with the metal material and the non-metal material to form a metal sulfur oxide on the optical absorption layer.

Methods of manufacturing a solar cell

Disclosed is a planar waveguide element including a first cylindrical lens disposed based on an z-axis and configured to collimate beams emitted from a plurality of emitters of a laser diode bar; a lens array configured to gather the beam emitted from each emitter via the first cylindrical lens; a plurality of first waveguides existing on an x-y plane by a number of the plurality of emitters and configured to gather at one place via a bending section; a taper configured to connect the lens array and each first waveguide, a width of the taper being narrower from the lens array to the plurality of first waveguide; and a combined waveguide configured to combine the plurality of first waveguides into one.

Planar waveguide element

Provided is a single junction type CIGS thin film solar cell, which includes a CIGS light absorption layer manufactured using a single junction. The single junction type CIGS thin film solar cell includes a substrate, a back contact deposited on the substrate, a light absorption layer deposited on the back contact and including a P type CIGS layer and an N type CIGS layer coupled to the P type CIGS layer using a single junction, and a reflection prevention film deposited on the light absorption layer.

Single junction type cigs thin film solar cell and method for manufacturing the thin film solar cell

Provided are an etching method for a multi-layered structure of semiconductors in groups III-V and a method of manufacturing a VCSEL using the etching method. According to the etching method, a stacked structure including a first semiconductor layer and a second semiconductor layer is exposed to a plasma of a mixture consisting of Cl, Ar, CH, and Hto etch the stacked structure, so that a mirror layer of the VCSEL is formed. The first semiconductor layer is formed of a semiconductor in groups III-V and the second semiconductor layer is formed of a semiconductor in groups III-V, other than the semiconductor of the first semiconductor layer. At least part of a lower mirror layer, a lower electrode layer, an optical gain layer, an upper electrode layer, and an upper mirror layer is etched using one time of an etching process, so that a clean and smooth etched surface is obtained.

Method of etching for multi-layered structure of semiconductors in group III-V and method for manufacturing vertical cavity surface emitting laser device

Provided is a semiconductor optical device having a current-confined structure. The device includes a first semiconductor layer of a first conductivity type which is formed on a semiconductor substrate and includes one or more material layers, a second semiconductor layer which is formed on the first semiconductor layer and includes one or more material layers, and a third semiconductor layer of a second conductivity type which is formed on the second semiconductor layer and includes one or more material layers. One or more layers among the first semiconductor layer, the second semiconductor, and the third semiconductor layer have a mesa structure. A lateral portion of at least one of the material layers constituting the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer is recessed, and the recess is partially or wholly filled with an oxide layer, a nitride layer or a combination of them. The semiconductor optical device having the current-confined region is mechanically reliable, highly thermally conductive, and commercially preferable and can be used in a wavelength range for optical communications.

Semiconductor optical device having current-confined structure

A DBR structure in a VCSEL diode, a method of manufacturing the DBR structure, and a VCSEL diode are provided. The DBR structure in the VCSEL diode includes: an InAlGaAs layer having a predetermined refractive index and disposed on an InP substrate; a first InAlAs layer having a lower refractive index than the InAlGaAs layer and disposed on the InAlGaAs layer; an InP layer having a lower refractive index than the InAlGaAs layer and disposed on the first InAlAs layer; and a second InAlAs layer having a lower refractive index than the InAlGaAs layer and disposed on the InP layer. Thus, the DBR structure can reduce optical loss due to type-II band line-up at a junction between the InAlGaAs layer and the InP layer, and thus improve device characteristics.

Growing community of inventors

Daejeon, South Korea

Won Seok Han