Patents by Inventor Kyoo Choi

Kyoo Choi 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).

  • Patent number: 5891596
    Abstract: A method for fabricating a phase shifting mask includes the steps of: forming a light shielding layer on a light transmitting substrate; forming a first mask on the light shielding layer; forming plural openings in the light shielding layer through to the substrate by patterning the light shielding layer using the first mask; forming a second mask layer on the light transmitting substrate and on the first mask layer pattern; patterning the second mask layer to form a second mask that exposes selected ones of the openings in the light shielding layer; and forming a phase shifting region in the light transmitting substrate using the first and second masks. The method prevents the light shielding layer from being damaged by the etching process that forms the phase shifting region, and makes it possible to transfer a pattern accurately, thus achieving a phase shifting mask having high reliability.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: April 6, 1999
    Assignee: LG Semicon Co., Ltd.
    Inventor: Yong Kyoo Choi
  • Patent number: 5845503
    Abstract: A refrigerator having an opening degree control means and a control method thereof which have an opening degree control means for controlling a refrigerant flow provided into each evaporator, and thus enhance an energy efficiency, in a refrigerator which independently cools or maintains the freezing and refrigerating compartments at different temperatures by including an evaporator in each of the freezing and refrigerating compartments.
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: December 8, 1998
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Dong-Kyoo Choi
  • Patent number: 5824438
    Abstract: The structure of a phase shift mask and a method of manufacturing the same are disclosed. A phase shifting mask in accordance with the present invention comprises a light transmitting substrate, a phase shifting layer formed on the upper side of the light transmitting substrate, an adhesive layer formed on the phase shifting layer, and a light shielding layer formed on the adhesive layer. Accordingly, when etching the phase shifting layer, the light shielding layer is protected by the adhesive layer. The adhesive strength is increased due to the adhesive layer formed between the phase shifting layer and the light shielding layer, thereby much improving the reliability of the phase shifting mask.
    Type: Grant
    Filed: January 31, 1997
    Date of Patent: October 20, 1998
    Assignee: LG Semicon Co., Ltd.
    Inventors: Yong-Kyoo Choi, Chan-Min Park, Jun-Seok Lee
  • Patent number: 5770336
    Abstract: A lithography mask and a method for fabricating a mask are disclosed. The method includes the steps of forming a plurality of insulating film patterns on a semiconductor substrate, forming a plurality of doped regions in the semiconductor substrate, forming a conductive layer on the doped regions and the insulating film patterns, and forming a plurality of passages through the semiconductor substrate. The lithography mask includes a semiconductor substrate, a plurality of patterns formed on the semiconductor substrate, a plurality of doped regions formed in the semiconductor substrate between the patterns, a plurality of trenches formed on a lower portion of the semiconductor substrate to expose the doped regions, and a plurality of first holes each penetrating a corresponding one of the doped regions.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: June 23, 1998
    Assignee: LG Semicon Co., Ltd
    Inventor: Yong-Kyoo Choi
  • Patent number: 5732566
    Abstract: A heat pump heating and cooling system includes a compressor, indoor and outdoor heat exchangers, and two expansion devices. Interposed between the expansion devices is a cut-off device which permits refrigerant to flow between the indoor and outdoor heat exchanges while the compressor is operating, and blocks such flow while the compressor is idle, thereby isolating high and low pressure fluids from one another while the compressor is idle.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: March 31, 1998
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Dong Kyoo Choi
  • Patent number: 5699181
    Abstract: A deformable mirror device and a manufacturing method thereof, which decreases the possibility of damage to a substrate having an address scanning circuit and increases the efficiency of light reflection of a moving mirror. First and second moving mirrors and first and second posts are fabricated on a substrate. An address scanning circuit (SRAM) is fabricated on another substrate, independently. Finally, both the substrates are combined. The second post is vertically formed by sputtering after the second moving mirror is formed.
    Type: Grant
    Filed: April 25, 1996
    Date of Patent: December 16, 1997
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Bum-Kyoo Choi
  • Patent number: 5658695
    Abstract: A method is provided for fabricating a phase shift mask of the out rigger sub-resolution type capable of accurately fabricating an ultra-fine semiconductor circuit.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: August 19, 1997
    Assignee: Goldstar Electron Co., Ltd.
    Inventor: Yong Kyoo Choi
  • Patent number: 5650347
    Abstract: A method of manufacturing a lightly doped drain MOS transistor having the double shallow junction is disclosed including the steps of forming a gate and a gate insulating film on a semiconductor substrate of a first conductivity type, sequentially; forming, on the top and sidewalls of the gate, on side edges of the gate insulating layer, and on the substrate, an insulating film including two kinds of impurities whose diffusivity and conductivity type are different from each other forming a cap insulating film on the insulating film; performing the heat treatment process thereby to form impurity regions of a second conductivity type and impurity regions of the first conductivity type surrounding the impurity regions of the second conductivity type, on both sides of the gate in the substrate; etching the insulating film and the cap insulating film thereby to form sidewall spacers on both sides of the gate; and ion-implanting an impurity of the second conductivity type in the substrate thereby to form impurity r
    Type: Grant
    Filed: July 26, 1995
    Date of Patent: July 22, 1997
    Assignee: LG Semicon Co., Ltd.
    Inventor: Yong-Kyoo Choi