Electronics and Telecommunications Research Institute

Byueng-Su Yoo

Hyo-Hoon Park

Hye Yong Chu

O-Kyun Kwon

Hye-Yong Chu

Kyung-Sook Hyun

Young-Gu Ju

El-Hang Lee

Kwang-Joon Kim

Seok-Ho Song

Young-Wan Choi

Pyong-Woon Park

Seon-Gyu Han

Tae-Hyung Zyung

Jong-Tai Lee

Kyu-Suk Lee

Disclosed is a surface-emitting laser device which eliminates an absorption loss of a p-type doped layer and reduces a scattering loss in a mirror layer and a carrier loss due to a current induction, comprising a first conductive type of semiconductor substrate; a bottom mirror layer formed on the semiconductor substrate and composed of a first conductive type of semiconductor layer; an active layer formed on the bottom mirror layer; an electron leakage barrier layer formed on the active layer and having an energy gap larger than the active layer; a current induction layer formed on the electron leakage barrier layer and a second conductive type of semiconductor layer; a current extension layer formed on the current induction layer and composed of the second conductive type of semiconductor layer; and a top mirror layer formed on the current extension layer, wherein the top mirror layer includes undoped center portion and its both end having the second conductive type of dopant diffusion region.

Long wavelength surface-emitting semiconductor laser device and method for manufacturing the same

A folded cavity laser for generating a laser beam, includes a substrate provided with a distributed Bragg reflector (DBR); an active medium formed above the DBR for amplifying the laser beam; a first and a second mirrors formed on sides of the active medium, respectively, for making a horizontal cavity and for reflecting the amplified laser beam to the DBR; and a microlens, formed on the substrate opposite the DBR, for making the amplified laser beam astigmatic after passing therethrough.

Folded cavity laser

A method of manufacturing a polarization switching surface-emitting laser in which a laser resonance wavelength depends on changing the polarization of the laser, by changing the refractivity of a compound semiconductor mirror layer of the laser depending on polarizations using an electro-optic effect of compound semiconductor materials such as GsAs and applying an electric field thereto.

Polarization switching surface-emitting laser and a method of manufacturing the same

The present invention relates to a wavelength demultiplexer. More particularly, the present invention provides the wavelength demultiplexer with straight optical waveguide that minimizes the bending loss of optical waveguide caused in the wavelength demultiplexer. A wavelength demultiplexer with straight optical waveguide in accordance with the present invention comprises an optical power distributor, a plurality of optical waveguides, and an optical power combiner. The optical power distributor evenly divides multiplexed input light by intensity. The number of optical waveguide transmits the divided multiplexed light and causes constant optical path length differences among adjacent waveguides. The optical waveguide is straight optical waveguide and includes two parts of different effective refractive indices. The optical power combiner receives output signals of the plurality of optical waveguides and separates the output signals by phase.

Wavelength demultiplexer without waveguide bending loss

The present invention relates to a semiconductor photoelectric device including a InAs layer formed to monoatomic thickness sandwiched between spacer layers adjacent to an emitter to maximize a difference in energy between two quantum states in accumulation layer of a resonant tunneling diode having a double barrier structure, resulting in separating the resonant tunneling current determined by two quantum states of the triangular well in accumulation layer of resonant tunneling diode, even when light of a low intensity is irradiated to the surface of the resonant tunneling diode. Thus, there is provided an optical controlled resonant tunneling diode, making it possible to manufacturing a switching device for controlling an electric signal using light source by adjusting, using light, the resonant tunneling determined by an excited state of the triangular well.

Optical controlled resonant tunneling diode

A three-dimensional cavity surface emitting laser structure and a fabrication method thereof which are capable of effectively controlling the characteristic of the transverse mode by applying independent electrical field to a side wall of an active region and concentrating a current flow along, inside of the active region. The structure includes a protrusion portion of a bottom mirror region formed on a substrate, an insulation film formed in a sidewall of a laser post having an active region extended from the protrusion and a top mirror region, and a sidewall metal mirror layer electrically separated from n-type and p-type electrodes for independently applying an electric field.

Three-dimensional cavity surface emitting laser structure and

A method for manufacturing a surface-emitting laser array device is disclosed. In order to control the polarization characteristics of the surface-emitting laser, the surface-emitting laser array device according to the present invention can be manufactured by alternately arranging the surface-emitting laser formed by inclining a cavity in the &lt;110&gt; and &lt;110&gt; direction in accordance with the row or the column direction of the surface-emitting laser, so that the polarization characteristics of the surface-emitting laser in two directions which are relatively perpendicular to each other may be obtained. According to the present invention, it has an advantageous effect that the interaction between the adjacent laser beams can be minimized with maintaining the symmetric feature of the lasing beam when manufacturing an integrated surface-emitting laser array device. Further, since the traveling direction of the lasing beam can be controlled depending upon the polarization characteristics, not only the optical interconnection or optical switching can easily be performed, but also the device can effectively be applied to the device, for example, the magneto-optic disk which is sensitive to the polarization characteristics.

Method of manufacturing polarization-controlled surface emitting laser

A method for producing a vertical-cavity surface-emitting laser, includes the steps of: forming a bottom mirror layer, an active layer and a top mirror layer on a semiconductor substrate; forming an antireflection layer on a rear surface of the semiconductor substrate; selectively etching peripheral portions of the antireflection layer to form a first electrode; defining laser emission portions through etching processing; forming a hydrogenated barrier over an entire surface of the resultant structure; forming a post; forming a passivation layer through the hydrogenating of the exposed top mirror layer and the portions of the active layer; forming a planarization film after the partial exposure of the top mirror and forming a second electrode pad to which the exposed top mirror layer contacts.

Method for producing a hydrogenated vertical-cavity surface-emitting

An improved parallel optical logic operator provides a path for light to pass through substrates in which a light source and an optical logic device are arranged. An optical logic device operates by transmission of light forwarded to a predetermined direction. This increases integration efficiency of the system by eliminating optical parts for changing the light path. A unit chip includes a laser array for generating a predetermined light in accordance with an electrical signal for a logic process, a laser array substrate on which via holes are formed for passing light, a microlens array for converting the light beam emitted from each laser device of the laser array into a parallel light beam for passing through the via hole, and an optical logic circuit array formed with a combination of an S-SEED which performs a logic function by transmission of the light signal through an optical window in S-SEED. A plurality of unit chips are laminated so that the light emitted from the laser device of one of the unit chips passes through an optical logic circuit of a corresponding unit chip and can be made incident on the optical logic circuit in the next unit chip through a via hole.

Compact optical logic operator array

Disclosed is an ultrafast optical switching device having two types of multiple quantum well structures to be connected with each other, the device comprising a semi-insulating substrate; and a first and a second multiple quantum well structure formed sequentially on the substrate and united with each other to produce a double-junction multiple quantum well structure. Each of the multiple quantum well structures has nonlinear optical effects and two life time constants present while switching off in the device. One of the life time constants corresponds to a short life time constant to be determined dependent on electrons in the double-junction multiple quantum well structure and the other of the life time constants corresponds to a long life time constant to be determined dependent on holes and lattices therein. The multiple quantum well structures are formed in such a manner that short life time constants thereof may be in-phase with each other and long life time constants thereof may be out-of-phase to each other. The multiple quantum well structures are formed differently from each other in composition.

Growing community of inventors

Taejon, South Korea

Byueng-Su Yoo