Patents by Inventor Chang-jin Sohn

Chang-jin Sohn 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: 5985491
    Abstract: A photolithographic projection system for selectively irradiating a photosensitive layer on a wafer according to a predetermined pattern on a mask is discussed. The photolithographic projection system includes a radiation source which generates radiation such as light. A reflector reflects the radiation from the radiation source on a path which intersects the wafer. This reflector includes a radiation reflecting portion and a phase-shifting and partially reflecting portion adjacent the radiation reflecting portion. The reflecting portion may include a plurality of reflecting portions surrounded by the absorbing portion, or the reflecting portion may surround the absorbing portion. Alternately, the reflector may include a reflecting portion and an absorbing portion adjacent the reflecting portion. Related methods are also discussed.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: November 16, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Cheol-hong Kim, Chang-jin Sohn
  • Patent number: 5978138
    Abstract: A projection method uses a modified illumination method for a lithography process of semiconductor device, and a projection system and mask use the projection method. An object is exposed by removing the vertical incident component of light passed through a condenser lens. Zero-order diffracted light interferes destructively and the oblique component of .-+.first-order diffracted light, interferes constructively. The obliquely incident component light illuminates a mask having a pattern formed thereon. The vertical incident component of the light is removed by a phase difference of light due to a grating mask or a grating pattern formed on the back surface of the conventional mask. The resolution of a lithography process is improved due to the increased contrast, and the depth of focus is also increased. Thus, patterns for 64 Mb DRAMs can be formed using a conventional projection exposure system.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: November 2, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-young Kang, Cheol-hong Kim, Seong-oon Choi, Woo-sung Han, Chang-jin Sohn
  • Patent number: 5808796
    Abstract: A projection method uses a modified illumination method for a lithography process of semiconductor device, and a projection system and mask use the projection method. An object is exposed by removing the vertical incident component of light passed through a condenser lens. Zero-order diffracted light interferes destructively and the oblique component of -/+ first-order diffracted light, interferes constructively. The obliquely incident component light illuminates a mask having a pattern formed thereon. The vertical incident component of the light is removed by a phase difference of light due to a grating mask or a grating pattern formed on the back surface of the conventional mask. The resolution of a lithography process is improved due to the increased contrast, and the depth of focus is also increased. Thus, patterns for 64 Mb DRAMs can be formed using a conventional projection exposure system.
    Type: Grant
    Filed: April 7, 1997
    Date of Patent: September 15, 1998
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-young Kang, Cheol-hong Kim, Seong-oon Choi, Woo-sung Han, Chang-jin Sohn
  • Patent number: 5726738
    Abstract: An aperture for an off-axis illumination (OAI) and a projection exposure apparatus which employs the same. In the aperture for an OAI having a light-intercepting region and a light-transmitting region, at least a portion of the light-transmitting region is prismoidal and diffracts incident light toward the periphery of the condenser lens. Accordingly, light intensity is increased due to an increased light-transmitting region, which can lead to a reduction in the exposure time required for photolithography procedures and to an increased productivity of semiconductor devices.
    Type: Grant
    Filed: August 6, 1996
    Date of Patent: March 10, 1998
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chang-jin Sohn, Cheol-hong Kim, Woo-sung Han
  • Patent number: 5725973
    Abstract: A photo mask and method for manufacturing the same increase the capacitance of a capacitor by improving the proximity effect of a mask pattern. The photo mask includes a transparent substrate, an opaque mask pattern for defining an optical transmission area on the substrate, and an optical transmittance control film pattern for suppressing proximity effect in the optical transmission area. The proximity effect is suppressed by forming an optical transmittance control film pattern in the transmission area between the individual portions of the opaque mask pattern, so that the mask pattern shape can be exactly transferred onto a substrate.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: March 10, 1998
    Assignee: Samsung Electronic Co., Ltd.
    Inventors: Woo-sung Han, Chang-jin Sohn
  • Patent number: 5661601
    Abstract: A projection method uses a modified illumination method for a lithography process of semiconductor device, and a projection system and mask use the projection method. An object is exposed by removing the vertical incident component of light passed through a condenser lens. Zero-order diffracted light interferes destructively and the oblique component of .-+. first-order diffracted light, interferes constructively. The obliquely incident component light illuminates a mask having a pattern formed thereon. The vertical incident component of the light is removed by a phase difference of light due to a grating mask or a grating pattern formed on the back surface of the conventional mask. The resolution of a lithography process is improved due to the increased contrast, and the depth of focus is also increased. Thus, patterns for 64 Mb DRAMs can be formed using a conventional projection exposure system.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: August 26, 1997
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-young Kang, Cheol-hong Kim, Seong-oon Choi, Woo-sung Han, Chang-jin Sohn
  • Patent number: 5608576
    Abstract: A projection method uses a modified illumination method for a lithography process of semiconductor device, and a projection system and mask use the projection method. An object is exposed by removing the vertical incident component of light passed through a condenser lens. Zero-order diffracted light interferes destructively and the oblique component of -/+ first-order diffracted light, interferes constructively. The obliquely incident component light illuminates a mask having a pattern formed thereon. The vertical incident component of the light is removed by a phase difference of light due to a grating mask or a grating pattern formed on the back surface of the conventional mask. The resolution of a lithography process is improved due to the increased contrast, and the depth of focus is also increased. Thus, patterns for 64 Mb DRAMs can be formed using a conventional projection exposure system.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: March 4, 1997
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Woo-sung Han, Chang-jin Sohn, Ho-young Kang, Cheol-hong Kim, Seong-oon Choi
  • Patent number: 5585210
    Abstract: A mask pattern for manufacturing a resist pattern of a semiconductor device through photolithography is provided with an additional mask pattern whose size is such that resist patterns are not formed after exposure on the spaces thereof. Using such a mask pattern, a manufacturing method of fine patterns enables the formation of specific patterns having an improved profile.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: December 17, 1996
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Dong-Seon Lee, Chang-Jin Sohn, Woo-Sung Han, Gee-Hoo Kim
  • Patent number: 5547788
    Abstract: A mask and a method for manufacturing the same, which can form a correct pattern on a semiconductor wafer having steps, includes a mask substrate having steps oppositely corresponding to steps on said semiconductor wafer and an opaque mask pattern for cutting off light from the mask substrate to thereby enable the same exposure focus to be provided to the step and non-step regions on the semiconductor wafer. Further, a clean and correct pattern can be formed by controlling the amount of exposure irradiated onto the step and non-step regions on the semiconductor wafer.
    Type: Grant
    Filed: March 4, 1994
    Date of Patent: August 20, 1996
    Assignee: Samsung Electronic Co., Ltd.
    Inventors: Woo-sung Han, Chang-jin Sohn
  • Patent number: 5446587
    Abstract: A projection method uses a modified illumination method for a lithography process of semiconductor device, and a projection system and mask use the projection method. An object is exposed by removing the vertical incident component of light passed through a condenser lens. Zero-order diffracted light interferes destructively and the oblique component of .-+. first-order diffracted light, interferes constructively. The obliquely incident component light illuminates a mask having a pattern formed thereon. The vertical incident component of the light is removed by a phase difference of light due to a grating mask or a grating pattern formed on the back surface of the conventional mask. The resolution of a lithography process is improved due to the increased contrast, and the depth of focus is also increased. Thus, patterns for 64 Mb DRAMs can be formed using a conventional projection exposure system.
    Type: Grant
    Filed: September 2, 1993
    Date of Patent: August 29, 1995
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-young Kang, Cheol-hong Kim, Seong-oon Choi, Woo-sung Han, Chang-jin Sohn