Patents by Inventor Lap Chan

Lap Chan 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: 6566208
    Abstract: A method for forming a sub-quarter micron MOSFET having an elevated source/drain structure is described. A gate electrode is formed over a gate dielectric on a semiconductor substrate. Ions are implanted into the semiconductor substrate to form lightly doped regions using the gate electrode as a mask. Thereafter, dielectric spacers are formed on sidewalls of the gate electrode. A polysilicon layer is deposited overlying the semiconductor substrate, gate electrode, and dielectric spacers wherein the polysilicon layer is heavily doped. The polysilicon layer is etched back to leave polysilicon spacers on the dielectric spacers. Dopant is diffused from the polysilicon spacers into the semiconductor substrate to form source and drain regions underlying the polysilicon spacers.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: May 20, 2003
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Yang Pan, Lee Yong Meng, Leung Ying Keung, Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek, Ravi Sundarensan
  • Patent number: 6566215
    Abstract: A novel method for forming short channel MOS transistors is described. A hard mask stack is formed over a substrate. A first opening is formed through a top portion of the hard mask stack. Oxide spacers are formed on sidewalls of the first opening thereby forming a second opening smaller than the first opening. The second opening is filled with a polysilicon layer. Thereafter, the oxide spacers are removed. First ions are implanted into the substrate underlying the removed oxide spacers to form source/drain extensions. Then, the polysilicon layer is removed wherein the first opening remains and wherein the substrate is exposed in a channel region. A gate dielectric layer is formed over the channel region. The first opening is filled with a gate electrode material that is polished back to form a gate electrode. The hard mask stack is removed using the gate electrode as a mask.
    Type: Grant
    Filed: June 6, 2002
    Date of Patent: May 20, 2003
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Yung Fu Chong, Lap Chan
  • Publication number: 20030092251
    Abstract: A method for forming a region of low dielectric constant nanoporous material is disclosed. In one embodiment, the present method includes the step of preparing a microemulsion. The method of the present embodiment then recites applying the microemulsion to a surface above which it is desired to form a region of low dielectric constant nanoporous material. Next, the present method recites subjecting the microemulsion, which has been applied to the surface, to a thermal process such that the region of low dielectric constant nanoporous material is formed above the surface.
    Type: Application
    Filed: November 13, 2001
    Publication date: May 15, 2003
    Applicant: CHARTERED SEMICONDUCTORS MANUFACTURED LIMITED
    Inventors: Soo Choi Pheng, Lap Chan, Wang Cui Yang, Siew Yong Kong, Alex See
  • Publication number: 20030075758
    Abstract: A method to form a closely-spaced, vertical NMOS and PMOS transistor pair in an integrated circuit device is achieved. A substrate comprise silicon implanted oxide (SIMOX) wherein an oxide layer is sandwiched between underlying and overlying silicon layers. Ions are selectively implanted into a first part of the overlying silicon layer, to form a drain, channel region, and source for an NMOS transistor. The drain is formed directly overlying the oxide layer, the channel region is formed overlying the drain, and the source is formed overlying the channel region. Ions are selectively implanted into a second part of the overlying silicon layer to form a drain, channel region, and source for a PMOS transistor. The drain is formed directly overlying the oxide layer, the PMOS channel region is formed overlying the drain, and the source is formed overlying the channel region. The PMOS transistor drain is in contact with said NMOS transistor drain.
    Type: Application
    Filed: September 12, 2002
    Publication date: April 24, 2003
    Applicant: CHARTERED SEMICONDUCTOR MANUFACTURING LTD.
    Inventors: Ravi Sundaresan, Yang Pan, James Yong Meng Lee, Ying Keung Leung, Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek
  • Publication number: 20030077863
    Abstract: A Flash memory is provided having a trilayer structure of rapid thermal oxide/germanium (Ge) nanocrystals in silicon dioxide (SiO2)/sputtered SiO2 cap with demonstrated via capacitance versus voltage (C-V) measurements having memory hysteresis due to Ge nanocrystals in the middle layer of the trilayer structure. The Ge nanocrystals are synthesized by rapid thermal annealing of a co-sputtered Ge+SiO2 layer.
    Type: Application
    Filed: March 1, 2002
    Publication date: April 24, 2003
    Inventors: Wee Kiong Choi, Wai Kin Chim, Vivian Ng, Lap Chan
  • Patent number: 6544824
    Abstract: A method of manufacturing a vertical transistor. A doped region is formed in a substrate. We form sequentially on the substrate: a first spacer dielectric layer, a first gate electrode, a second spacer dielectric layer, a second gate electrode and a third spacer dielectric layer. A trench is formed through the first spacer dielectric layer, the first gate electrode, the second spacer dielectric layer, the second gate electrode and the third spacer dielectric layer. The trench has sidewalls. A gate dielectric layer is formed over the sidewalls of the trench. We form sequentially, in the trench: a first doped layer, a first channel layer, a second doped layer, a third doped layer, a second channel layer, and a fourth doped layer. A cap layer is formed over the structure. Contacts are preferably formed to the doped region, doped layers and gate electrodes.
    Type: Grant
    Filed: January 3, 2002
    Date of Patent: April 8, 2003
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Yelehanka Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek, Ravi Sundaresan, Yang Pan, James Lee Yong Meng, Ying Keung
  • Patent number: 6541327
    Abstract: A method to form elevated source/drain (S/D) over staircase shaped openings in insulating layers. A gate structure is formed over a substrate. The gate structure is preferably comprised of a gate dielectric layer, gate electrode, first spacers, and hard mask. A first insulating layer is formed over the substrate and the gate structure. A resist layer is formed having an opening over the gate structure and over a lateral area adjacent to the gate structure. We etch the insulating layer through the opening in the resist layer. The etching removes a first thickness of the insulating layer to form a source/drain (S/D) opening. We remove the first spacers and hardmask to form a source/drain (S/D) contact opening. We implant ions into the substrate through the source/drain (S/D) contact opening to form lightly doped drain regions.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: April 1, 2003
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Lap Chan, Elgin Quek, Ravi Sundaresan, Yang Pan, James Yong Meng Lee, Ying Keung Leung, Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng
  • Patent number: 6531750
    Abstract: A method of forming shallow junction MOSFETs is achieved. A gate oxide layer is formed overlying a substrate. A first electrode layer, of polysilicon or metal, is deposited. A silicon nitride layer is deposited. The silicon nitride layer and the first electrode layer are etched through to form temporary MOSFET gates. Ions are implanted into the substrate to form lightly doped junctions. A spacer layer is deposited. The spacer layer and the gate oxide layer are anisotropically etched to form sidewall spacers. Ions are implanted into the substrate to form heavily doped junctions. The silicon nitride layer is etched away. A second electrode layer, of polysilicon or metal, is deposited overlying the substrate, the sidewall spacers, and the first polysilicon layer. The second electrode layer is polished down to the top surfaces of the sidewall spacers to complete the MOSFETs and to form permanent gates and conductive connections to the source and drain junctions.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: March 11, 2003
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Lap Chan, Cher Liang Cha, Ravishankar Sundaresan
  • Publication number: 20030022450
    Abstract: A method for forming a sub-quarter micron MOSFET having an elevated source/drain structure is described. A gate electrode is formed over a gate dielectric on a semiconductor substrate. Ions are implanted into the semiconductor substrate to form lightly doped regions using the gate electrode as a mask. Thereafter, dielectric spacers are formed on sidewalls of the gate electrode. A polysilicon layer is deposited overlying the semiconductor substrate, gate electrode, and dielectric spacers wherein the polysilicon layer is heavily doped. The polysilicon layer is etched back to leave polysilicon spacers on the dielectric spacers. Dopant is diffused from the polysilicon spacers into the semiconductor substrate to form source and drain regions underlying the polysilicon spacers.
    Type: Application
    Filed: July 25, 2001
    Publication date: January 30, 2003
    Applicant: Chartered Semiconductor manufacturing Ltd.
    Inventors: Yang Pan, James Lee Yong Meng, Leung Ying Keung, Yelehanka Ramachandramurthy Predeep, Jia Zhen Zheng, Lap Chan, Elgin Quek, Ravi Sundarensan
  • Patent number: 6511884
    Abstract: A method of fabricating an isolated vertical transistor comprising the following steps. A wafer having a first implanted region selected from the group comprising a source region and a drain region is provided. The wafer further includes STI areas on either side of a center transistor area. The wafer is patterned down to the first implanted region to form a vertical pillar within the center transistor area using a patterned hardmask. The vertical pillar having side walls. A pad dielectric layer is formed over the wafer, lining the vertical pillar. A nitride layer is formed over the pad dielectric layer. The structure is patterned and etched through the nitride layer and the pad dielectric layer; and into the wafer within the STI areas to form STI trenches within the wafer. The STI trenches are filled with insulative material to form STIs within STI trenches. The patterned nitride and pad dielectric layers are removed. The patterned hardmask is removed.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: January 28, 2003
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Elgin Quek, Ravi Sundaresan, Yang Pan, Yong Meng Lee, Ying Keung Leung, Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan
  • Publication number: 20030017710
    Abstract: A method of forming a sloped staircase STI structure, comprising the following steps. a) A substrate having an upper surface is provided. b) A patterned masking layer is formed over the substrate to define an STI region. The patterned masking layer having exposed sidewalls. c) The substrate is etched a first time through the masking layer to form a first step trench within the STI region. The first step trench having exposed sidewalls. d) Continuous side wall spacers are formed on the exposed patterned masking layer and first step trench sidewalls. e) The substrate is etched a second time using the masking layer and the continuous sidewall spacers as masks to form a second step trench within the STI region. The second step trench having exposed sidewalls. f) Second side wall spacers are formed on the second step trench sidewalls. g) Steps e) and f) are repeated x more times to create x+2 total step trenches and x+2 total side wall spacers on x+2 total step trench sidewalls.
    Type: Application
    Filed: July 19, 2001
    Publication date: January 23, 2003
    Applicant: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Pan Yang, James Lee Yong Meng, Leung Ying Keung, Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek, Ravi Sundaresan
  • Patent number: 6501122
    Abstract: A new method of fabricating a stacked gate Flash EEPROM device having an improved interpoly oxide layer is described. A gate oxide layer is provided on the surface of a substrate. A first polysilicon layer is deposited overlying the gate oxide layer and patterned to form a floating gate. Source and drain regions associated with the floating gate are formed within the substrate. An oxide layer is deposited overlying the floating gate and the substrate. The oxide layer is polished away until the top of the oxide layer is even with the top of the floating gate. A second polysilicon layer is deposited overlying the oxide layer and the first polysilicon layer of the floating gate wherein the second polysilicon layer has a smooth surface. An interpoly dielectric layer is deposited overlying the second polysilicon layer. A third polysilicon layer is deposited overlying the interpoly dielectric layer.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: December 31, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Lap Chan, Cher Liang Cha
  • Patent number: 6495200
    Abstract: A method of for electroless copper deposition using a Pd/Pd acetate seeding layer formed in using only two components (Pd acetate and solvent) to form an interconnect for a semiconductor device. The invention has two preferred embodiments. The first embodiment forms a Key seed layer composed of Pd/Pd acetate by a spin-on or dip process for the electroless plating of a Cu plug. The second embodiment forms a Pd passivation cap layer over the Cu plug to prevent the Cu plug from oxidizing.
    Type: Grant
    Filed: December 7, 1998
    Date of Patent: December 17, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Lap Chan, Fong Yau Li, Hou Tee Ng
  • Publication number: 20020173106
    Abstract: A method for forming a gate dielectric having regions with different dielectric constants. A low-K dielectric layer is formed over a semiconductor structure. A dummy dielectric layer is formed over the low-K dielectric layer. The dummy dielectric layer and low-K dielectric layer are patterned to form an opening. The dummy dielectric layer is isontropically etched selectively to the low-K dielectric layer to form a stepped gate opening. A high-K dielectric layer is formed over the dummy dielectric and in the stepped gate opening. A gate electrode is formed on the high-K dielectric layer.
    Type: Application
    Filed: July 16, 2002
    Publication date: November 21, 2002
    Applicant: CHARTERED SEMICONDUCTOR MANUFACTURING LTD.
    Inventors: James Yong Meng Lee, Ying Keung Leung, Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek, Ravi Sundaresan, Yang Pan
  • Patent number: 6483148
    Abstract: A method of forming a self-aligned elevated transistor using selective epitaxial growth is described. An oxide layer is provided overlying a semiconductor substrate. The oxide layer is etched through to the semiconductor substrate to form a trench having a lower portion contacting the substrate and an upper portion having a width larger than the width of the lower portion. A silicon layer is grown within the trench using selective epitaxial growth wherein the silicon layer fills the lower portion and partially fills the upper portion. Nitride spacers are formed on the sidewalls of the trench. A polysilicon layer is deposited overlying the oxide layer and within the trench and etched back to form a gate electrode within the trench between the nitride spacers. The nitride spacers are etched away where they are not covered by the gate electrode leaving thin nitride spacers on sidewalls of the gate electrode.
    Type: Grant
    Filed: February 1, 2002
    Date of Patent: November 19, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Lap Chan, Cher Liang Cha
  • Publication number: 20020155703
    Abstract: A novel method for forming a C54 phase titanium disilicide film in the fabrication of an integrated circuit is described. A semiconductor substrate is provided having silicon regions to be silicided. A titanium layer is deposited overlying the silicon regions to be silicided. The substrate is subjected to a first annealing whereby the titanium is transformed to phase C40 titanium disilicide where it overlies the silicon regions and wherein the titanium not overlying the silicon regions is unreacted. The unreacted titanium layer is removed. The substrate is subjected to a second annealing whereby the phase C40 titanium disilicide is transformed to phase C54 titanium disilicide to complete formation of a phase 54 titanium disilicide film in the manufacture of an integrated circuit.
    Type: Application
    Filed: April 20, 2001
    Publication date: October 24, 2002
    Applicant: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Shaoyin Chen, Ze Xiang Shen, Alex See, Lap Chan
  • Patent number: 6468906
    Abstract: An interconnect line on an IMD layer on a semiconductor device is formed in an interconnect hole in the IMD layer. The interconnect hole has walls and a bottom in the IMD layer. A diffusion barrier is formed on the walls and the bottom of the hole. Fill the interconnect hole with a copper metal line. Perform a CMP step to planarize the device and to remove copper above the IMD layer. Deposit a passivating metal layer on the surface of the copper metal line encapsulating the copper metal line at the top of the hole. Alternatively, a blanket deposit of a copper metal line layer covers the diffusion layer and fills the interconnect hole with a copper metal line. Perform a CMP process to planarize the device to remove copper above the IMD layer. Deposit a passivating metal layer on the surface of the copper metal line encapsulating the copper metal line at the top of the hole in a self-aligned deposition process.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: October 22, 2002
    Assignees: Chartered Semiconductor Manufacturing Ltd., National University of Singapore, Namyang Technological University of Singapore, Institute of Microelectronics
    Inventors: Lap Chan, Kuan Pei Yap, Kheng Chok Tee, Flora S. Ip, Wye Boon Loh
  • Patent number: 6468877
    Abstract: A method of fabricating an air-gap spacer of a semiconductor device, comprising the following steps. A semiconductor substrate having at least a pair of STIs defining an active region is provided. A gate electrode is formed on the substrate within the active region. The gate electrode having an underlying gate dielectric layer. A liner oxide layer is formed over the structure, covering the sidewalls of the gate dielectric layer, the gate electrode, and over the top surface of the gate electrode. A liner nitride layer is formed over the liner oxide layer. A thick oxide layer is formed over the structure. The thick oxide, liner nitride, and liner oxide layers are planarized level with the top surface of the gate electrode, and exposing the liner oxide layer at either side of the gate electrode.
    Type: Grant
    Filed: July 19, 2001
    Date of Patent: October 22, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek, Ravi Sundaresan, Yang Pan, James Yong Meng Lee, Ying Keung Leung
  • Patent number: 6461887
    Abstract: A method of forming an inverted staircase shaped STI structure comprising the following steps. A semiconductor substrate having an overlying oxide layer is provided. The substrate having at least a pair of active areas defining an STI region therebetween. The oxide layer is etched a first time within the active areas to form first step trenches. The first step trenches having exposed sidewalls. Continuous side wall spacers are formed on said exposed first step trench sidewalls. The oxide layer is etched X+1 more successive times using the previously formed step side wall spacers as masks to form successive step trenches within the active areas. Each of the successive step trenches having exposed sidewalls and have side wall spacers successively formed on the successive step trench exposed sidewalls. The oxide layer is etched a final time using the previously formed step side wall spacers as masks to form final step trenches exposing the substrate within the active areas.
    Type: Grant
    Filed: January 3, 2002
    Date of Patent: October 8, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek, Ravi Sundaresan, Yang Pan, James Yong Meng Lee, Ying Keung Leung
  • Patent number: 6461900
    Abstract: A method to form a closely-spaced, vertical NMOS and PMOS transistor pair in an integrated circuit device is achieved. A substrate comprises silicon implanted oxide (SIMOX) wherein an oxide layer is sandwiched between underlying and overlying silicon layers. Ions are selectively implanted into a first part of the overlying silicon layer to form a drain, channel region, and source for an NMOS transistor. The drain is formed directly overlying the oxide layer, the channel region is formed overlying the drain, and the source is formed overlying the channel region. Ions are selectively implanted into a second part of the overlying silicon layer to form a drain, channel region, and source for a PMOS transistor. The drain is formed directly overlying the oxide layer, the PMOS channel region is formed overlying the drain, and the source is formed overlying the channel region. The PMOS transistor drain is in contact with said NMOS transistor drain.
    Type: Grant
    Filed: October 18, 2001
    Date of Patent: October 8, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Ravi Sundaresan, Yang Pan, James Lee Young Meng, Ying Keung Leung, Yelehanka Ramachandramurthy Pradeep, Jia Zhen Zheng, Lap Chan, Elgin Quek