Patents by Inventor Ko-Min Chang

Ko-Min Chang 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: 20070218633
    Abstract: A memory device is formed on a semiconductor substrate. A select gate electrode and a control gate electrode are formed adjacent to one another. One of either the select gate electrode or the control gate electrodes is recessed with respect to the other. The recess allows for a manufacturable process with which to form silicided surfaces on both the select gate electrode and the control gate electrode.
    Type: Application
    Filed: March 15, 2006
    Publication date: September 20, 2007
    Inventors: Erwin Prinz, Ko-Min Chang, Robert Steimle
  • Publication number: 20070020856
    Abstract: forming a first gate electrode within the trench after forming the discontinuous storage elements. At least one discontinuous storage element lies along the wall of the trench at an elevation between an upper surface of the first gate electrode and a primary surface of the substrate. The process can also include forming a second gate electrode overlying the first gate electrode and the primary surface of the substrate.
    Type: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Michael Sadd, Ko-Min Chang, Gowrishankar Chindalore, Cheong Hong, Craig Swift
  • Publication number: 20070018222
    Abstract: An electronic device can include discontinuous storage elements that lie within a trench. In one embodiment, the electronic device can include a substrate having a trench that includes a wall and a bottom. The electronic device can also include a portion of discontinuous storage elements that lie within the trench. The electronic device can also include a first gate electrode, wherein at least one discontinuous storage element lies along the wall of the trench at an elevation between and upper surface of the first gate electrode and a primary surface of the substrate. The electronic device can also include a second gate electrode overlying the first gate electrode and the primary surface of the substrate. In another embodiment, a conductive line can be electrically connected to one or more rows or columns of memory cells, and another conductive line can be more rows or more columns of memory cells.
    Type: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Michael Sadd, Ko-Min Chang, Gowrishankar Chindalore, Cheong Hong, Craig Swift
  • Patent number: 6939767
    Abstract: A non-volatile memory (10) includes at least two buried bit lines (45, 47) formed within a semiconductor substrate (12), a charge storage layer (18) overlying the semiconductor substrate (12); a control gate (26) overlying the charge storage layer (18); an insulating liner (30) overlying the control gate; and first and second conductive sidewall spacer control gates (32, 34). Multiple programmable charge storage regions (42) and (41, 44) are created within the charge storage layer (18) beneath respective ones of the control gate (26) and the first and second sidewall spacer control gates (32, 34). Also, the non-volatile memory (10) is a virtual ground NOR type multi-bit flash EEPROM (electrically erasable programmable read only memory). By using conductive sidewall spacers as the control gates, a very dense multi-bit non-volatile memory can be manufactured.
    Type: Grant
    Filed: November 19, 2003
    Date of Patent: September 6, 2005
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Alexander B. Hoefler, Ko-Min Chang
  • Publication number: 20050106812
    Abstract: A non-volatile memory (10) includes at least two buried bit lines (45, 47) formed within a semiconductor substrate (12), a charge storage layer (18) overlying the semiconductor substrate (12); a control gate (26) overlying the charge storage layer (18); an insulating liner (30) overlying the control gate; and first and second conductive sidewall spacer control gates (32, 34). Multiple programmable charge storage regions (42) and (41, 44) are created within the charge storage layer (18) beneath respective ones of the control gate (26) and the first and second sidewall spacer control gates (32, 34). Also, the non-volatile memory (10) is a virtual ground NOR type multi-bit flash EEPROM (electrically erasable programmable read only memory). By using conductive sidewall spacers as the control gates, a very dense multi-bit non-volatile memory can be manufactured.
    Type: Application
    Filed: November 19, 2003
    Publication date: May 19, 2005
    Inventors: Alexander Hoefler, Ko-Min Chang
  • Patent number: 6844588
    Abstract: A semiconductor device includes a non-volatile memory, such as an electrically erasable programmable read only memory (EEPROM) array of memory cells. The memory is arranged as an array of cells in rows and columns. Each column of the array is located within an isolated well, common to the cells in the column but isolated from other wells of other columns. The array is programmed by pulsing potentials to each column, with isolation of results for each column. In one embodiment, the memory cells are devoid of floating gate devices and use a non-conductive charge storage layer to store charges. In another embodiment, the memory cells store charges in nanocrystals.
    Type: Grant
    Filed: December 19, 2001
    Date of Patent: January 18, 2005
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig A. Cavins, Ko-Min Chang
  • Patent number: 6791883
    Abstract: A non-volatile memory having a thin film dielectric storage element is programmed by hot carrier injection (HCI) and erased by tunneling. The typical structure for the memory cells for this type of memory is silicon, oxide, nitride, oxide, and silicon (SONOS). The hot carrier injection provides relatively fast programming for SONOS, while the tunneling provides for erase that avoids the difficulties with the hot hole erase (HHE) type erase that generally accompanies hot carrier injection for programming. HHE is significantly more damaging to dielectrics leading to reliability issues. HHE also has a relatively narrow area of erasure that may not perfectly match the pattern for the HCI programming leaving an incomplete erasure. The tunnel erase effectively covers the entire area so there is no concern about incomplete erase. Although tunnel erase is slower than HHE, erase time is generally less critical in a system operation than is programming time.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: September 14, 2004
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Jane A. Yater, Alexander B. Hoefler, Ko-Min Chang, Erwin J. Prinz, Bruce L. Morton
  • Publication number: 20030235083
    Abstract: A non-volatile memory having a thin film dielectric storage element is programmed by hot carrier injection (HCI) and erased by tunneling. The typical structure for the memory cells for this type of memory is silicon, oxide, nitride, oxide, and silicon (SONOS). The hot carrier injection provides relatively fast programming for SONOS, while the tunneling provides for erase that avoids the difficulties with the hot hole erase (HHE) type erase that generally accompanies hot carrier injection for programming. HHE is significantly more damaging to dielectrics leading to reliability issues. HHE also has a relatively narrow area of erasure that may not perfectly match the pattern for the HCI programming leaving an incomplete erasure. The tunnel erase effectively covers the entire area so there is no concern about incomplete erase. Although tunnel erase is slower than HHE, erase time is generally less critical in a system operation than is programming time.
    Type: Application
    Filed: June 24, 2002
    Publication date: December 25, 2003
    Inventors: Craig T. Swift, Jane A. Yater, Alexander B. Hoefler, Ko-Min Chang, Erwin J. Prinz, Bruce L. Morton
  • Publication number: 20030111672
    Abstract: A semiconductor device includes a non-volatile memory, such as an electrically erasable programmable read only memory (EEPROM) array of memory cells. The memory is arranged as an array of cells in rows and columns. Each column of the array is located within an isolated well, common to the cells in the column but isolated from other wells of other columns. The array is programmed by pulsing potentials to each column, with isolation of results for each column. In one embodiment, the memory cells are devoid of floating gate devices and use a non-conductive charge storage layer to store charges. In another embodiment, the memory cells store charges in nanocrystals.
    Type: Application
    Filed: December 19, 2001
    Publication date: June 19, 2003
    Inventors: Craig A. Cavins, Ko-Min Chang
  • Patent number: 5969383
    Abstract: An EEPROM device includes a split-gate FET (10) having a source (36), a drain (22), a select gate (16) adjacent the drain (22), and a control gate (32) adjacent the source (36). When programming the split-gate FET (10), electrons are accelerated in a portion of a channel region (38) between the select gate (16) and the control gate (32), and then injected into a nitride layer (24) of an ONO stack (25) underlying the control gate (32). The split-gate FET (10) is erased by injecting holes from the channel region (38) into the charge nitride layer (24). When reading data from the split-gate FET (10), a reading voltage is applied to the drain (22) adjacent the select gate (16). Data is then read from the split-gate FET (10) by sensing a current flowing in a bit line coupled to the drain (22).
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: October 19, 1999
    Assignee: Motorola, Inc.
    Inventors: Kuo-Tung Chang, Ko-Min Chang, Wei-Ming Chen, Keith Forbes, Douglas R. Roberts
  • Patent number: 5949706
    Abstract: A memory circuit and method of formation uses a transmission gate (24) as a select gate. The transmission gate (24) contains a transistor (30) which is an N-channel transistor and a transistor (28) which is a P-channel transistor. The transistors (28 and 30) are electrically connected in parallel. The use of the transmission gate (24) as a select gate allows reads and writes to occur to a memory cell storage device (i.e. a capacitor (32), a floating gate (22), etc.) without a significant voltage drop occurring across the transmission gate. In addition, EEPROM technology is more compatible with EPROM/flash technology when using a transmission gate as a select gate within EEPROM devices.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: September 7, 1999
    Assignee: Motorola, Inc.
    Inventors: Ko-Min Chang, Bruce L. Morton, Clinton C. K. Kuo, Keith E. Witek, Kent J. Cooper
  • Patent number: 5898619
    Abstract: A memory circuit and method of formation uses a transmission gate (24) as a select gate. The transmission gate (24) contains a transistor (30) which is an N-channel transistor and a transistor (28) which is a P-channel transistor. The transistors (28 and 30) are electrically connected in parallel. The use of the transmission gate (24) as a select gate allows reads and writes to occur to a memory cell storage device (i.e. a capacitor (32), a floating gate (22), etc.) without a significant voltage drop occurring across the transmission gate. In addition, EEPROM technology is more compatible with EPROM/flash technology when using a transmission gate as a select gate within EEPROM devices.
    Type: Grant
    Filed: May 16, 1994
    Date of Patent: April 27, 1999
    Inventors: Ko-Min Chang, Bruce L. Morton, Clinton C. K. Kuo, Keith E. Witek, Kent J. Cooper
  • Patent number: 5731238
    Abstract: An integrated circuit (10) is formed using jet vapor deposition (JVD) silicon nitride. A non-volatile memory device (11) has a tunnel dielectric layer (27) and an inter-poly dielectric layer (31) that can be formed from JVD silicon nitride. A transistor (12,13,40) is formed that has a gate dielectric material made from JVD silicon nitride. In addition, a passivation layer (47) can be formed overlying a semiconductor device (40) that is formed from JVD silicon nitride.
    Type: Grant
    Filed: August 5, 1996
    Date of Patent: March 24, 1998
    Assignee: Motorola Inc.
    Inventors: Craig Allan Cavins, Hsing-Huang Tseng, Ko-Min Chang
  • Patent number: 5705415
    Abstract: A semiconductor device is formed having a floating gate memory cell (11) that has its channel region (33) oriented vertically with a portion of the channel region (33) that is not capacitively coupled to a floating gate (32). The memory cell (11) is less likely to be over-erased and may be programmed by source-side injection. The cell (11) may not need to be repaired after erasing. Less power may be consumed during programming compared to hot electron injection and Fowler-Nordheim tunneling.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: January 6, 1998
    Assignee: Motorola, Inc.
    Inventors: Marius K. Orlowski, Ko-Min Chang
  • Patent number: 5706228
    Abstract: A memory array (25) having a selected memory cell (10) and an unselected memory cell (30) is programmed and read. Each memory cell in the memory array (25) contains an isolation transistor (22) and a floating gate transistor (23). To program the selected memory cell (10), programming voltages are applied to a control gate line (21), a drain line (14), an isolation line (19), and a source line (12). To reduce the effects of the drain disturb problem, a gate terminal (32) of the unselected memory cell (30) is held at a positive voltage. To read selected memory cell (10), a read voltage is applied to an isolation gate line (31) of unselected memory cell (30) which insures that the unselected memory cell (30) does not conduct or contribute to leakage current and power consumption during the read operation.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: January 6, 1998
    Assignee: Motorola, Inc.
    Inventors: Kuo-Tung Chang, Craig A. Cavins, Ko-Min Chang, Bruce L. Morton, George L. Espinor
  • Patent number: 5646060
    Abstract: An EEPROM cell (40) includes a floating gate transistor (47) and an isolation transistor (45). Both a floating gate (48) and an isolation gate (46) are formed on a tunnel dielectric (44) within the cell. The isolation gate is coupled to a doped source region (52) of the floating gate transistor. The isolation transistor is not biased during a program operation of the cell, enabling a thin tunnel dielectric (less than 120 angstroms) to be used beneath all portions of both gates within the cell. Thus, the need for both a conventional tunnel dielectric and a gate dielectric is eliminated. The cell tolerates over-erasure, can be programmed at low programming voltages, and has good current drive due to the thin tunnel dielectric throughout the cell.
    Type: Grant
    Filed: May 30, 1995
    Date of Patent: July 8, 1997
    Assignee: Motorola, Inc.
    Inventors: Ko-Min Chang, Danny Pak-Chum Shum, Kuo-Tung Chang
  • Patent number: 5633186
    Abstract: A process for fabricating a non-volatile memory cell (10) in a semiconductor device includes the formation of a doped region (28) in a semiconductor substrate (40) underlying a floating gate electrode (16) and separated therefrom by a tunnel dielectric layer (44). Stress induced failure of the tunnel dielectric layer (44) is avoided by laterally diffusing dopant atoms under the floating gate electrode (16) after completely fabricating both the floating gate electrode (16) and the underlying tunnel dielectric layer (44).
    Type: Grant
    Filed: August 14, 1995
    Date of Patent: May 27, 1997
    Assignee: Motorola, Inc.
    Inventors: Danny P. C. Shum, Ko-Min Chang, William J. Taylor, Jr.
  • Patent number: 5605855
    Abstract: A process for fabricating a graded-channel MOS device includes the formation of a masking layer (16) on the surface of a semiconductor substrate (10) and separated from the surface by a gate oxide layer (12). A first doped region (22) is formed in a channel region (20) of the semiconductor substrate (10) using the masking layer (16) as a doping mask. A second doped region (24) is formed in the channel region (20) and extends from the principal surface (14) of the semiconductor substrate (10) to the first doped region (22). A gate electrode (34) is formed within an opening (18) in the masking layer (16) and aligned to the channel region (20). Upon removal of the masking layer (16) source and drain regions (36, 38) are formed in the semiconductor substrate (10) and aligned to the gate electrode (34).
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: February 25, 1997
    Assignee: Motorola Inc.
    Inventors: Ko-Min Chang, Marius Orlowski, Craig Swift, Shih-Wei Sun, Shiang-Chyong Luo
  • Patent number: 5474947
    Abstract: A process for fabricating an improved nonvolatile memory device includes the formation of a control gate electrode (70) which overlies a floating gate electrode (42) and is separated therefrom by an inter-level-dielectric layer (62). The control gate electrode (70) and the underlying floating gate electrode (42) form a stacked gate structure (72) located in the active region (44) of a semiconductor substrate (40). An electrically insulating sidewall spacer (54) is formed at the edges of the floating gate electrode (42) and electrically isolates the control gate (70) from the semiconductor substrate (40). During the fabrication process, implanted memory regions (56, 58) are formed in the active region (44) prior to the formation of control gate electrode (70). A word-line (68) and the control gate (70) are formed by anisotropic etching of a semiconductor layer (66), which is deposited to overlie inter-level-dielectric layer (62).
    Type: Grant
    Filed: December 27, 1993
    Date of Patent: December 12, 1995
    Assignee: Motorola Inc.
    Inventors: Ko-Min Chang, Bruce L. Morton, Henry Y. Choe, Clinton C. K. Kuo
  • Patent number: 5471422
    Abstract: An EEPROM cell (40) includes a floating gate transistor (47) and an isolation transistor (45). Both a floating gate (48) and an isolation gate (46) are formed on a tunnel dielectric (44) within the cell. The isolation gate is coupled to a doped source region (52) of the floating gate transistor. The isolation transistor is not biased during a program operation of the cell, enabling a thin tunnel dielectric (less than 120 angstroms) to be used beneath all portions of both gates within the cell. Thus, the need for both a conventional tunnel dielectric and a gate dielectric is eliminated. The cell tolerates over-erasure, can be programmed at low programming voltages, and has good current drive due to the thin tunnel dielectric throughout the cell.
    Type: Grant
    Filed: April 11, 1994
    Date of Patent: November 28, 1995
    Assignee: Motorola, Inc.
    Inventors: Ko-Min Chang, Danny P. Shum, Kuo-Tung Chang