Patents by Inventor Subhash Gupta

Subhash Gupta 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: 20020100794
    Abstract: A method of bonding a bonding element to a metal bonding pad comprises the following steps. A semiconductor structure having an exposed, recessed metal bonding pad within a layer opening is provided. The layer has an upper surface. A conductive cap having a predetermined thickness is formed over the metal bonding pad. A bonding element is bonded to the conductive cap to form an electrical connection with the metal bonding pad.
    Type: Application
    Filed: March 15, 2002
    Publication date: August 1, 2002
    Applicant: CHARTERED SEMICONDUCTOR MANUFACTURING LTD.
    Inventors: Kwok Keung Paul Ho, Simon Chooi, Yi Xu, Yakub Aliyu, Mei Sheng Zhou, John Leonard Sudijono, Subhash Gupta, Sudipto Ranendra Roy
  • Publication number: 20020096190
    Abstract: A method for cleaning a semiconductor structure using vapor phase condensation with a thermally vaporized cleaning agent, a hydrocarbon vaporized by pressure variation, or a combination of the two. In the thermally vaporized cleaning agent process, a semiconductor structure is lowered into a vapor blanket in a thermal gradient cleaning chamber at atmospheric pressure formed by heating a liquid cleaning agent below the vapor blanket and cooling the liquid cleaning agent above the vapor blanket causing it to condense and return to the bottom of the thermal gradient cleaning chamber. The semiconductor structure is then raised above the vapor blanket and the cleaning agent condenses on all of the surfaces of the semiconductor structure removing contaminants and is returned to the bottom of the chamber by gravity.
    Type: Application
    Filed: January 19, 2001
    Publication date: July 25, 2002
    Applicant: Chartered Semiconductor Manufacturing Inc.
    Inventors: Sudipto Ranendra Roy, Yi Xu, Simon Chooi, Yakub Aliyu, Mei Sheng Zhou, John Leonard Sudijono, Paul Kwok Keung Ho, Subhash Gupta
  • Patent number: 6415973
    Abstract: A method of bonding a bonding element to a metal bonding pad, comprising the following steps. A semiconductor structure having an exposed metal bonding pad within a passivation layer opening is provided. The bonding pad has an upper surface. A bonding element is positioned to contact the bonding pad upper surface. A bonding solution is applied within the passivation layer opening, covering the bonding pad and a portion of the bonding element. The structure is annealed by heating said bonding element to selectively solidify the bonding solution proximate said contact of said bonding element to said bonding pad, bonding the bonding element to the bonding pad.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: July 9, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Kwok Keung Paul Ho, Simon Chooi, Yi Xu, Mei Sheng Zhou, Yakub Aliyu, John Leonard Sudijono, Subhash Gupta, Sudipto Ranendra Roy
  • Patent number: 6417088
    Abstract: A method of forming a conductive cap layer over a metal bonding pad comprises the following steps. A semiconductor structure is provided having an exposed, recessed metal bonding pad within a layer opening. The layer has an upper surface. The exposed metal bonding pad is treated with a solution containing soluble metal ions to form a conductive cap over the metal bonding pad. The conductive cap layer is comprised of the solution metal and has a predetermined thickness. An external bonding element may then be bonded to the conductive cap, forming an electrical connection with the metal bonding pad.
    Type: Grant
    Filed: July 24, 2000
    Date of Patent: July 9, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Kwok Keung Paul Ho, Yi Xu, Simon Chooi, Yakub Aliyu, Mei Sheng Zhou, John Leonard Sudijono, Subhash Gupta, Sudipto Ranendra Roy
  • Publication number: 20020076877
    Abstract: A new method of forming silicon nitride sidewall spacers has been achieved. In addition, a new device profile for a silicon nitride sidewall spacer has been achieved. An isolation region is provided overlying a semiconductor substrate. Polysilicon traces are provided. A liner oxide layer is formed overlying the polysilicon traces and the insulator layer. A silicon nitride layer is formed overlying the liner oxide layer. A polysilicon or amorphous silicon layer is deposited overlying the silicon nitride layer. The polysilicon or amorphous silicon layer is completely oxidized to form a temporary silicon dioxide layer. The temporary silicon dioxide layer is rounded in the corners due to volume expansion during the oxidation step. The temporary silicon dioxide layer is anisotropically etched through to expose horizontal surfaces of the silicon nitride layer while leaving vertical sidewalls of the temporary silicon dioxide layer.
    Type: Application
    Filed: February 19, 2002
    Publication date: June 20, 2002
    Applicant: CHARTERED SEMICONDUCTOR MANUFACTURING LTD.
    Inventors: Subhash Gupta, Yelehanka Ramachandramurthy Pradeep, Vijai Kumar Chhagan
  • Publication number: 20020064941
    Abstract: A method of forming amorphous silicon spacers followed by the forming of metal nitride over the spacers in a copper damascene structure—single, dual, or multi-structure—is disclosed in order to prevent the formation of fluorides in copper. In a first embodiment, the interconnection between the copper damascene and an underlying copper metal layer is made by forming an opening from the dual damascene structure to the underlying copper layer after the formation of the metal nitride layer over the amorphous silicon spacers formed on the inside walls of the dual damascene structure. In the second embodiment, the interconnection between the dual damascene structure and the underlying copper line is made from the dual damascene structure by etching into the underlying copper layer after the forming of the amorphous silicon spacers and before the forming of the metal nitride layer.
    Type: Application
    Filed: January 14, 2002
    Publication date: May 30, 2002
    Applicant: CHARTERED SEMICONDUCTOR MANUFACTURING LTD.
    Inventors: Simon Chooi, Subhash Gupta, Mei Sheng Zhou, Sang Ki Hong
  • Patent number: 6394114
    Abstract: An inexpensive and safe copper removal method in the fabrication of integrated circuits is described. Copper is stripped or removed by a chemical mixture comprising an ammonium salt, an amine, and water. The rate of copper stripping can be controlled by varying the concentration of the ammonium salt component and the amount of water in the mixture. Also a novel chemical mixture for stripping copper and removing copper contamination is provided. The novel chemical mixture for removing or stripping copper comprises an ammonium salt, an amine, and water. For example, the novel chemical mixture may comprise ammonium fluoride, water, and ethylenediamine in a ratio of 1:1:1.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: May 28, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Subhash Gupta, Simon Chooi, Paul Ho, Mei Sheng Zhou
  • Patent number: 6391783
    Abstract: A method of forming a metal plug, comprising the following steps. An etched dielectric layer, over a conductive layer, over a semiconductor structure are provided. The etched dielectric layer having a via hole and an exposed periphery. The etched dielectric layer is treated with at least one alkaline earth element source to form an in-situ metal barrier layer within the dielectric layer exposed periphery. A metal plug is formed within the via hole wherein the in-situ metal barrier layer prevents diffusion of the metal from the metal plug into the dielectric oxide layer.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: May 21, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: John Sudijono, Yakub Aliyu, Mei Sheng Zhou, Simon Chooi, Subhash Gupta, Sudipto Roy, Paul Ho, Yi Xu
  • Patent number: 6391732
    Abstract: A new method of forming silicon nitride sidewall spacers has been achieved. In addition, a new device profile for a silicon nitride sidewall spacer has been achieved. An isolation region is provided overlying a semiconductor substrate. Polysilicon traces are provided. A liner oxide layer is formed overlying the polysilicon traces and the insulator layer. A silicon nitride layer is formed overlying the liner oxide layer. A polysilicon or amorphous silicon layer is deposited overlying the silicon nitride layer. The polysilicon or amorphous silicon layer is completely oxidized to form a temporary silicon dioxide layer. The temporary silicon dioxide layer is rounded in the corners due to volume expansion during the oxidation step. The temporary silicon dioxide layer is anisotropically etched through to expose horizontal surfaces of the silicon nitride layer while leaving vertical sidewalls of the temporary silicon dioxide layer.
    Type: Grant
    Filed: June 16, 2000
    Date of Patent: May 21, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Subhash Gupta, Yelehanka Ramachandramurthy, Vijai Kumar Chhagan
  • Patent number: 6378759
    Abstract: A method of bonding a bonding element to a metal bonding pad comprises the following steps. A semiconductor structure having an exposed, recessed metal bonding pad within a layer opening is provided. The layer has an upper surface. A conductive cap having a predetermined thickness is formed over the metal bonding pad. A bonding element is bonded to the conductive cap to form an electrical connection with the metal bonding pad.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: April 30, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Kwok Keung Paul Ho, Simon Chooi, Yi Xu, Yakub Aliyu, Mei Sheng Zhou, John Leonard Sudijono, Subhash Gupta, Sudipto Ranendra Roy
  • Patent number: 6380084
    Abstract: A method to form robust dual damascene interconnects by decoupling via and connective line trench filling has been achieved. A first dielectric layer is deposited overlying a silicon nitride layer. A shielding layer is deposited. The shielding layer, the first dielectric layer, and the silicon nitride layer are patterned to form via trenches. A first barrier layer is deposited to line the trenches. The via trenches are filled with a first copper layer by a single deposition or by depositing a seed layer and then electroless or electrochemical plating. The first copper layer is polished down to complete the vias. A second barrier layer is deposited. The second barrier layer is patterned to form via caps. A second dielectric layer is deposited. A capping layer is deposited. The capping layer and the second dielectric layer are patterned to form connective line trenches that expose a part of the via caps. A third barrier layer is deposited to line the connective line trenches.
    Type: Grant
    Filed: October 2, 2000
    Date of Patent: April 30, 2002
    Assignee: Chartered Semiconductor Manufacturing Inc.
    Inventors: Yeow Kheng Lim, Alex See, Cher Liang Cha, Subhash Gupta, Wang Ling Goh, Man Siu Tse
  • Patent number: 6380087
    Abstract: A method of fabricating a semiconductor wafer having at least one integrated circuit, the method comprising the following steps. A semiconductor wafer structure having at least an upper and a lower dielectric layer is provided. The semiconductor wafer structure having a bonding pad area and an interconnect area. At least one active interconnect having a first width is formed in the interconnect area, through the dielectric layers. A plurality of adjacent dummy plugs each having a second width is formed in the bonding pad area, through a portion of the dielectric layers. The semiconductor wafer structure is patterned and etched to form trenches through the upper dielectric layer. The trenches surround each of the at least one active interconnect and the dummy plugs whereby the upper dielectric level between the adjacent dummy plugs is removed. A metallization layer is deposited over the lower dielectric layer, filling the trenches at least to the upper surface of the remaining upper dielectric layer.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: April 30, 2002
    Assignee: Chartered Semiconductor Manufacturing Inc.
    Inventors: Subhash Gupta, Mei Sheng Zhou, Ramasamy Chockalingam
  • Publication number: 20020048950
    Abstract: An effective copper decontamination method in the fabrication of integrated circuits is achieved. An organic-based HFACAC decontamination compound in vapor phase is sprayed over elemental copper found on equipment or tools or as a spill wherein the compound reacts with all of the elemental copper and forms a volatile compound that can be flushed away thereby completing copper decontamination.
    Type: Application
    Filed: June 18, 2001
    Publication date: April 25, 2002
    Applicant: CHARTERED SEMICONDUCTOR MANUFACTURING LTD.
    Inventors: Yakub Aliyu, Simon Chooi, Mei Sheng Zhou, John Leonard Sudijono, Subhash Gupta, Sudipto Ranendra Roy, Paul Kwok Keung Ho, Yi Xu
  • Patent number: 6372636
    Abstract: A method of forming amorphous silicon spacers followed by the forming of metal nitride over the spacers in a copper damascene structure -single, dual, or multi-structure- is disclosed in order to prevent the formation of fluorides in copper. In a first embodiment, the interconnection between the copper damascene and an underlying copper metal layer is made by forming an opening from the dual damascene structure to the underlying copper layer after the formation of the metal nitride layer over the amorphous silicon spacers formed on the inside walls of the dual damascene structure. In the second embodiment, the interconnection between the dual damascene structure and the underlying copper line is made from the dual damascene structure by etching into the underlying copper layer after the forming of the amorphous silicon spacers and before the forming of the metal nitride layer.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: April 16, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Simon Chooi, Subhash Gupta, Mei-Sheng Zhou, Sangki Hong
  • Patent number: 6368958
    Abstract: A new method of depositing a copper layer, using disproportionation of Cu(I) ions from a solution stabilized by a polar organic solvent, for single and dual damascene interconnects in the manufacture of an integrated circuit device has been achieved. A dielectric layer, which may comprise a stack of dielectric material, is provided overlying a semiconductor substrate. The dielectric layer is patterned to form vias and trenches for planned dual damascene interconnects. A barrier layer is deposited overlying the dielectric layer to line the vias and trenches. A simple Cu(I) ion solution, stabilized by a polar organic solvent, is coated overlying said barrier layer. Water is added to the stabilized simple Cu(I) ion solution to cause disproportionation of the simple Cu(I) ion from the Cu(I) ion solution. A copper layer is deposited overlying the barrier layer.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: April 9, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Paul Kwok Keung Ho, Subhash Gupta, Mei Sheng Zhou, Simon Chooi
  • Patent number: 6365320
    Abstract: An anti-reflective film for deep ultraviolet (DUV) photolithograghy includes silicon oxime having the formula Si(1−x+y+z)NxOy:H2, wherein x, y, and z represent the atomic percentage of nitrogen, oxygen, and hydrogen, respectively. The film is characterized by a substantial lack of bonding between silicon atoms and oxygen atoms, and has a thickness of less than approximately 600 Å which is selected to produce destructive interference between incident and reflected light at a selected DUV wavelength.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: April 2, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: David K. Foote, Subhash Gupta
  • Patent number: 6365508
    Abstract: A new method to avoid post-etch cleaning in a metallization process is described. An insulating layer is formed over a first metal line in a dielectric layer overlying a semiconductor substrate. A via opening is etched through the insulating layer to the first metal line whereby a polymer forms on sidewalls of the via opening. The polymer is treated with a fluorinating agent whereby the polymer is converted to an inert layer. Thereafter, a second metal line is formed within the via opening wherein the inert layer acts is as a barrier layer to complete the metallization process in the fabrication of an integrated circuit device.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: April 2, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Mei Sheng Zhou, John Sudijono, Subhash Gupta, Sudipto Roy, Paul Ho, Xu Yi, Simon Chooi, Yakub Aliyu
  • Patent number: 6358821
    Abstract: A method of preventing copper transport on a semiconductor wafer, comprising the following steps. A semiconductor wafer having a front side and a backside is provided. Metal, selected from the group comprising aluminum, aluminum-copper, aluminum-silicon, and aluminum-copper-silicon is sputtered on the backside of the wafer to form a layer of metal. The back side sputtered aluminum layer may be partially oxidized at low temperature to further decrease the copper penetration possibility and to also provide greater flexibility in subsequent copper interconnect related processing. Once the back side layer is in place, the wafer can be processed as usual. The sputtered back side aluminum layer can be removed during final backside grinding.
    Type: Grant
    Filed: July 19, 2000
    Date of Patent: March 19, 2002
    Assignee: Chartered Semiconductor Manufacturing Inc.
    Inventors: Subhash Gupta, Simon Chooi, Sudipto Ranendra Roy, Paul Kwok Keung Ho, Xu Yi, Yakub Aliyu, Mei Sheng Zhou, John Leonard Sudijono
  • Patent number: 6352917
    Abstract: A new method of forming metal interconnect levels containing damascene interconnects and via plugs in the manufacture of an integrated circuit device has been achieved. The method creates a reversed dual damascene structure. A first dielectric layer is provided overlying a semiconductor substrate. The dielectric layer is patterned to form trenches for planned damascene interconnects. Insulating spacers may optionally be formed on the trench sidewalls. A conductive barrier layer is deposited overlying the dielectric layer and lining the trenches. A metal layer, preferably comprising copper, is deposited overlying the conductive barrier layer and filling the trenches. The metal layer and the conductive barrier layer are polished down to thereby form the damascene interconnects. A passivation layer may optionally be deposited. The damascene interconnects are patterned to form via plugs overlying the damascene interconnects.
    Type: Grant
    Filed: June 21, 2000
    Date of Patent: March 5, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Subhash Gupta, Mei-Sheng Zhou, Simon Chooi, Sangki Hong
  • Patent number: 6350675
    Abstract: This invention relates to a method of fabrication used for semiconductor integrated circuit devices, and more specifically, in the formation of self-aligned dual damascene interconnects and vias, which incorporates low dielectric constant intermetal dielectrics (IMD) and utilizes silylated top surface imaging (TSI) photoresist, with a single or multi-step selective reactive ion etch (RIE) process, to form trench/via opening. The invention incorporates the use of a silylated top surface imaging (TSI) resist etch barrier layer to form the via pattern, in the first level of a dual damascene process. Two variations of using the top surface imaging (TSI) resist, with and without leaving an exposed region in place, are described in the first and second embodiment of the invention, and in addition, a thin dielectric layer is made use of just below the resist layer.
    Type: Grant
    Filed: October 12, 2000
    Date of Patent: February 26, 2002
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Simon Chooi, Mei-Sheng Zhou, Subhash Gupta, Yi Xu