Patents by Inventor Tae Ahn

Tae Ahn has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20050020093
    Abstract: The method for forming a flowable dielectric layer is employed to use a barrier layer on sidewalls of patterned flowable dielectrics, thereby preventing a bridge phenomenon between adjacent contact plugs.
    Type: Application
    Filed: December 19, 2003
    Publication date: January 27, 2005
    Inventors: Sang-Tae Ahn, Dong-Sun Sheen, Seok-Pyo Song
  • Patent number: 6845185
    Abstract: A high-speed wavelength channel selector has properties of relatively easy manufacturing and easy extension to multi-channel integration, and a high-speed space and wavelength multiplexed channel selector uses the high-speed wavelength channel selector. The high-speed wavelength channel selector is integrated with electro-optic waveguide switches of non-crystalline materials, such as electro-optic polymers or glasses, in the middle of a pair of wavelength multiplexer and demultiplexer and the high-speed space and wavelength multiplexed channel selector has the photonic integrated circuit-type composition of a space multiplexed channel selector containing M electro-optic waveguide switches and an M×1 channel combiner, the high-speed wavelength channel selector, optical amplifier and a high-speed wavelength converter.
    Type: Grant
    Filed: April 15, 2002
    Date of Patent: January 18, 2005
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Kyong Hon Kim, Joon Tae Ahn, Yong Gyu Choi, Doo-Hee Cho
  • Publication number: 20050009281
    Abstract: Disclosed is the method of forming the gate in the semiconductor device. The present method can prevent abnormal oxidization and lifting at the interface of the stack gate consisting of polysilicon and a metal and can be applied to even the single metal gate, by replacing a re-oxidization process for recovering damage of the gate oxide film generated in the gate patterning process with the oxygen plasma treatment.
    Type: Application
    Filed: July 8, 2003
    Publication date: January 13, 2005
    Inventors: Kwan Lim, Heung Cho, Tae Ahn
  • Publication number: 20040246567
    Abstract: A gain-clamped optical amplifier including: optical reflection means installed on an input optical fiber or an output optical fiber; optical anti-reflection means installed on the optical fiber opposite to the optical fiber having the optical reflection means installed on; and an optical amplifier located between the optical reflection means and the optical anti-reflection means, for amplifying an input signal or an output signal, wherein an amplified spontaneous emission light emitted from the optical amplifier to the input optical fiber and the output optical fiber is reflected by the optical reflection means and amplified in the optical amplifier.
    Type: Application
    Filed: November 25, 2003
    Publication date: December 9, 2004
    Inventors: Joon Tae Ahn, Jong Moo Lee, Kyong Hon Kim
  • Publication number: 20040223677
    Abstract: The present invention relates to a polymer optical waveguide device using electrooptic effect. A polymer optical waveguide device has Mach-Zehnder interference system structure of dividing a path of a light applied to one optical waveguide into two paths, making the light travel through two optical waveguides, and combining the two optical waveguides into one optical waveguide. A heater is formed on branched one optical waveguide or two optical waveguides. Current is applied to the heater to change the index of refraction of the waveguides so that the bias of the optical device is controlled. The device of the present invention does not affected by the electric characteristic of the polymer but the reliability of the device operation can be improved.
    Type: Application
    Filed: November 10, 2003
    Publication date: November 11, 2004
    Inventors: Sun Tak Park, Jung Jin Ju, Jung Yun Do, Seung Koo Park, Myung Hyun Lee, Joon Tae Ahn, Jong Moo Lee
  • Publication number: 20040214405
    Abstract: A method for fabricating an isolation layer in a semiconductor device is disclosed. The disclosed method comprises steps of: forming a trench on a semiconductor substrate; forming a flowing insulating layer within the trench; making the insulating layer precise; and forming a precise insulating layer over an upper surface of the whole structure on which the flowing insulating layer is formed. According to the method of fabricating an isolation layer in a semiconductor device, occurrence of fine pores at adjacent active regions of sidewalls in a trench can be prevented.
    Type: Application
    Filed: December 17, 2003
    Publication date: October 28, 2004
    Inventors: Sang Tae Ahn, Sung Woong Chung, Hyun Chul Sohn
  • Publication number: 20040213535
    Abstract: Provided is a polymeric optical device comprising a substrate, a lower cladding layer formed on the substrate, at least one core layer pattern formed on a predetermined region of the lower cladding layer and an upper cladding layer having at least two sub-upper cladding layers and formed on the lower cladding layer in which the core layer pattern is formed, and a method of fabricating the same, whereby birefringence of a polymeric optical device could be improved and polarization dependence could be reduced by adjusting the thickness of the sub-upper cladding layer and the number of stacks thereof.
    Type: Application
    Filed: February 13, 2004
    Publication date: October 28, 2004
    Inventors: Jong Moo Lee, Sun Tak Park, Joon Tae Ahn, Jung Jin Ju, Myung Hyun Lee, Kyong Hon Kim
  • Publication number: 20040206426
    Abstract: Steel wires and steel rods with excellent cold forging properties and used in a manufacture of various machine components, which have relatively high strengths, are disclosed. The steel wires are produced by maintaining a product (n×YS) of a yield strength (YS) and a work hardening coefficient (n) obtained by a tensile test of the steel wire within a range of 4.0-11.0 kgf/mm2, without a need of additional quenching and tempering treatments after cold forging. There is no need to perform heating for spheroidizing annealing for a long time, and it is possible to produce quenched and tempered steel wires having excellent cold forging properties by quenching and tempering treatments in a short period of time.
    Type: Application
    Filed: May 3, 2004
    Publication date: October 21, 2004
    Applicant: Samhwa Steel Co., Ltd.
    Inventors: Soon-Tae Ahn, Yukio Yamaoka
  • Patent number: 6785449
    Abstract: The present invention relates to a multi-layer optical planar waveguide which is vertically coupled using multimode-interference couplers and to the method of manufacturing the same. The purpose of this invention is to increase the degree of integration on the multi-layer optical planar waveguide by applying the concept of via holes of the multi-layer printed circuit board (MLPCB) used in electronic circuits to the optical waveguide devices. According to the present invention, particularly, a multimode interference coupler of a stepped structure has the higher coupling ratio at relatively short length of interference than the usual multimode interference coupler. The present invention can implement a multimode interference coupler at a specialized spot while reducing evanescent field interference between the upper and lower optical waveguides out of the spot by separating the layers enough.
    Type: Grant
    Filed: August 6, 2002
    Date of Patent: August 31, 2004
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jong Moo Lee, Doo Hee Cho, Joon Tae Ahn, Myung Hyun Lee, Kyong Hon Kim
  • Patent number: 6769274
    Abstract: The present invention relates to a method of manufacturing a waveguide using an ion exchange process. The present invention controls the refractive index and the thickness of a surface layer on a glass substrate using an ion exchange process, forms the waveguide pattern on the surface layer by means of photolithography and etching process and coats with materials having the refractive index same to or lower than that of the glass substrate to form a cladding layer. Accordingly, the present invention can manufacture a planar waveguide, which is excellent in dimension control and reproducibility and has a sharp step wall.
    Type: Grant
    Filed: December 26, 2001
    Date of Patent: August 3, 2004
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Doo Hee Cho, Joon Tae Ahn, Min Yong Jeon, Kyong Hon Kim
  • Patent number: 6752880
    Abstract: Steel wires and steel rods with excellent cold forging properties and used in a manufacture of various machine components, which have relatively high strengths, are disclosed. The steel wires are produced by maintaining a product (n×YS) of a yield strength (YS) and a work hardening coefficient (n) obtained by a tensile test of the steel wire within a range of 4.0-11.0 kgf/2, without a need of additional quenching and tempering treatments after cold forging. There is no need to perform heating for spheroidizing annealing for a long time, and it is possible to produce quenched and tempered steel wires having excellent cold forging properties by quenching and tempering treatments in a short period of time.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: June 22, 2004
    Assignee: Samhwa Steel Co., Ltd.
    Inventors: Soon-Tae Ahn, Yukio Yamaoka
  • Publication number: 20040086229
    Abstract: The present invention relates to the polarization-independent optical polymeric intensity modulator independent of input signal using polymers with electro-optical property. To use the electro-optical property for electro-optical polymer, polymers must be poled by applying high voltage to the waveguide. The size of phase modulation caused by such an poling varies from the biggest value at polarization parallel to the poling to the smallest value at polarization perpendicular to the poling. Therefore, the performance of the electro-optical polymeric intensity modulator depends on the polarization state of input light. The present invention provides the polarization-independent optical polymeric intensity modulator capable of modulating the optical intensity without regard to the polarization of the input signal by making the polarizing directions of two optical paths of M-Z interferometer perpendicular each other.
    Type: Application
    Filed: December 30, 2002
    Publication date: May 6, 2004
    Inventors: Joon Tae Ahn, Sun Tak Park, Jong Moo Lee, Myung Hyun Lee, Kyong Hon Kim
  • Publication number: 20030231382
    Abstract: A direct optical modulation (DOM) type wavelength converter is provided. The provided wavelength converter is a gain-clamped semiconductor optical amplifier (GC-SOA), which does not require a continuous wave (CW) signal, or a semiconductor laser in itself, and reduces a coupling loss between the GC-SOA or the semiconductor laser and an optical fiber while improving an emission threshold of a laser. Therefore, the provided wavelength converter converts a wavelength of an input signal beam having a low intensity by controlling the intensity of the input signal.
    Type: Application
    Filed: September 18, 2002
    Publication date: December 18, 2003
    Inventors: Joon Tae Ahn, Jong Moo Lee, Kyong Hon Kim
  • Publication number: 20030228091
    Abstract: A wavelength selector to be used in WDM networks is provided. The wavelength selector is composed of a circulator, an arrayed waveguide grating (AWG), which is used for wavelength demultiplexing and multiplexing part, and an electro-optical (EO) switching part. The input light after the circulator is demultiplexed through the AWG part and each channel of the demultiplexed lights is modulated and reflected through the EO switching part which is formed as Michelson type interferometer with mirror parts returning the light to the AWG. The modulated and reflected light is multiplexed through the AWG and the direction is changed to the output through the circulator.
    Type: Application
    Filed: November 12, 2002
    Publication date: December 11, 2003
    Inventors: Jong-moo Lee, Joon-tae Ahn, Doo-hee Cho, Sun-tak Park, Myung-hyun Lee, Kyong-hon Kim
  • Publication number: 20030215189
    Abstract: The present invention relates to a multi-layer optical planar waveguide which is vertically coupled using multimode-interference couplers and to the method of manufacturing the same. The purpose of this invention is to increase the degree of integration on the multi-layer optical planar waveguide by applying the concept of via holes of the multi-layer printed circuit board (MLPCB) used in electronic circuits to the optical waveguide devices. According to the present invention, particularly, a multimode interference coupler of a stepped structure has the higher coupling ratio at relatively short length of interference than the usual multimode interference coupler. The present invention can implement a multimode interference coupler at a specialized spot while reducing evanescent field interference between the upper and lower optical waveguides out of the spot by separating the layers enough.
    Type: Application
    Filed: August 6, 2002
    Publication date: November 20, 2003
    Inventors: Jong Moo Lee, Doo Hee Cho, Joon Tae Ahn, Myung Hyun Lee, Kyong Hon Kim
  • Patent number: 6627533
    Abstract: A method of manufacturing an insulating film in a semiconductor device is disclosed. The method comprises the steps of forming a SOD film on the entire structure to fill any distance between conductive layer patterns and after performing a curing process, forming a hard mask film on the SOD film, wherein the silicon oxide film is deposited by plasma deposition method using SiH4 and N2O as a reaction gas at a low-temperature and at a low-pressure and wherein in a stabilization step, the supply amount of SiH4 is greater than that of N2O and in a deposition step, the supply amount of N2O is greater than that of SiH4.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: September 30, 2003
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventors: Sang Tae Ahn, Jung Gyu Song
  • Patent number: 6560251
    Abstract: There is disclosed a mode-locked optical fiber laser stabilizing apparatus for stabilizing the length of the optical fiber laser resonator by feedbacking the optical signals to the laser resonator, in the direction where the signal reflected by the optical fiber loop mirror is detected as an error signal to minimize the signal, and method thereof.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: May 6, 2003
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Min Yong Jeon, Hak Kyu Lee, Dong Sung Lim, Joon Tae Ahn, Do Il Chang, Kyong Hon Kim
  • Publication number: 20030066576
    Abstract: Steel wires and steel rods with excellent cold forging properties and used in a manufacture of various machine components, which have relatively high strengths, are disclosed. The steel wires are produced by maintaining a product (n×YS) of a yield strength (YS) and a work hardening coefficient (n) obtained by a tensile test of the steel wire within a range of 4.0-11.0 kgf/mm2, without a need of additional quenching or tempering treatments after cold forging. There is no need to perform heating for spheroidizing annealing for a long time, and it is possible to produce quenched and tempered steel wires having excellent cold forging properties by quenching and tempering treatments in a short period of time.
    Type: Application
    Filed: September 11, 2002
    Publication date: April 10, 2003
    Inventors: Soon-Tae Ahn, Yukio Yamaoka
  • Publication number: 20030058233
    Abstract: A scheme to reduce output variations in a column driver for a flat-panel display by sharing the characteristics of analog circuit is disclosed. An input multiplexer is provided between two neighboring digital inputs, and an output multiplexer is provided between two neighboring analog outputs so that the characteristics of neighboring analog circuits can be shared by multiplexing. The averaging effect by sharing reduces variations in the output. The multiplexing may be done either in time division or on a frame-by-frame basis.
    Type: Application
    Filed: August 30, 2002
    Publication date: March 27, 2003
    Inventors: Sung Tae Ahn, Yung Jin Jeon, Chen Young Jeong, Keunmyung Lee
  • Publication number: 20030058203
    Abstract: A single-chip column driver for organic light emitting diode (OLED) display is disclosed. Instead of using two column drivers for dual scan, the present invention uses one column driver driving both the upper and the lower OLED panels. The column driver has a two set of output circuitry: one for driving the upper panel and the other for driving the lower panel. The single chip solution of the present invention eliminates the problem of display uniformity without increasing the part count. The invention also enables independent control of RGB without further increasing the part count.
    Type: Application
    Filed: August 30, 2002
    Publication date: March 27, 2003
    Inventors: Sung Tae Ahn, Keunmyung Lee, Dae Young Ahn, Tae Kwang Park