Electronics and Telecommunications Research Institute

Mi Ran Park

O Kyun Kwon

Hyun Soo Kim

Dong Hun Lee

Jong Sool Jeong

Eun Soo Nam

Hyun Woo Song

Won Seok Han

Ki Soo Kim

Bong Ki Mheen

Yong Hwan Kwon

Byung Seok Choi

Jae Sik Sim

Albert J P Theuwissen

Disclosed is an optical source device. The optical source device includes: a mode converter configured to be optically coupled with an optical fiber; a semiconductor optical amplifier coupled with the mode converter, and configured to amplify an optical signal input through the optical fiber; and an electro absorption modulator coupled to the optical amplifier, and configured to modulate the amplified optical signal and output the modulated optical signal, in which each of the semiconductor optical amplifier and the optical absorption modulator includes a heater.

Reflective optical source device

Disclosed are a method and an apparatus for selecting a wavelength by a wavelength tunable optical receiver. The method of selecting a wavelength of a wavelength tunable optical receiver includes: receiving, by the wavelength tunable optical receiver, an optical signal from a wavelength tunable optical transmitter; filtering, by the wavelength tunable optical receiver, the optical signal through a low frequency band electrical signal filter, and obtaining a low frequency signal; determining, by the wavelength tunable optical receiver, whether the low frequency signal is a valid signal based on a current value of the low frequency signal; and when the low frequency signal is the valid signal, obtaining, by the wavelength tunable optical receiver, an enable condition of a wavelength tunable optical filter through which the low frequency signal is selected, in which the low frequency signal includes a control/monitoring signal.

Method and apparatus for selecting wavelength by wavelength tunable optical receiver

An image sensor with a shared photodiode is provided. The image sensor includes at least two unit pixels, each of which includes a photodiode, a diffusion region which gathers electrons from the photodiode, a transfer transistor which connects the photodiode with the diffusion region, and a readout circuit which reads out a signal from the diffusion region. Photodiodes of neighboring unit pixels are disposed symmetrically to be adjacent to one another to form a shared photodiode. The image sensor does not have a STI region which causes a dark current restricting its performance and does not require a basic minimum design factor (a distance or an area) related to a STI region. A region corresponding to a STI region may be used as a region of a photodiode or for additional pixel scaling. Therefore, a limitation in scaling of a photodiode is overcome, and pixel performance is improved in spite of pixel scaling.

Shared photodiode image sensor

Provided are a vertical cavity surface emitting laser (VCSEL) module providing accurate alignment between a VCSEL and a monitoring photodiode (MPD) for efficiently detecting light emitted by the VCSEL and a method of fabricating the VCSEL module. The VCSEL module includes: a first mirror layer, a first semiconductor conducting layer, an active layer, a tunnel junction layer, and a second semiconductor conducting layer sequentially formed on a first region in a substrate having first and second regions; a MPD disposed on a portion of the second semiconductor conducting layer in the first region; and a VCSEL including layers having the same shapes as the first mirror layer, the first semiconductor conducting layer, the active layer, the tunnel junction layer and the second semiconductor conducting layer in the first region, and a second mirror layer formed on a portion of the second semiconductor conducting layer, and sequentially formed on the second region in the substrate. The predetermined distance is set so that light emitted by the VCSEL can be detected by the MPD.

Vertical cavity surface emitting laser module having monitoring photodiode and method of fabricating the same

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 method for fabricating a filed effect transistor, the method comprising: depositing a first semiconductor layer and a second semiconductor layer on a substrate in sequence, which have a different bandgap from each other, and patterning the second semiconductor layer to have a mesa structure; forming a first resist pattern to expose the second semiconductor layer of a region where source and drain are to be formed; depositing a metal on a whole upper surface, and forming metallic source and drain by performing a lift-off process; performing heat treatment to form an ohmic contact between the source and the second semiconductor layer, and between the drain and the semiconductor layer; forming an insulating layer on the whole upper surface including the source and the drain, and forming a second photoresist pattern to expose the insulating layer at a portion where a gate is to be formed; exposing the second semiconductor layer at the portion where the gate is to be formed by etching the exposed portion of the insulating layer; and depositing the metal on the whole upper surface in a state that the temperature of the substrate is lowered to perform low temperature vacuum deposition, and forming a metallic gate by performing a lift-off process and an insulating layer removing process.

Growing community of inventors

Daejeon, South Korea

Mi Ran Park