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).

  • Patent number: 6225221
    Abstract: A new method of depositing a copper seed layer in the manufacture of an integrated circuit device has been achieved. The copper seed layer is thin and conformal and well-suited for subsequent electroless plating of copper. A dielectric layer, which may comprise a stack of dielectric material, is provided overlying a semiconductor substrate. The dielectric layer patterned to form vias and trenches for planned dual damascene interconnects. A barrier layer comprising tantalum, titanium, or tungsten is deposited overlying the dielectric layer to line the vias and trenches. A copper seed layer is deposited overlying the barrier layer by the reaction of CuF2 vapor with the barrier layer, and the integrated circuit is completed.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: May 1, 2001
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Paul Kwok Keung Ho, Mei Sheng Zhou, Subhash Gupta, Chockalingam Ramasamy
  • Patent number: 6184138
    Abstract: A new method is provided to construct a copper dual damascene structure. A layer of IMD is deposited over the surface of a substrate. A cap layer is deposited over this layer of IMD, the dual damascene structure is then patterned through the cap layer and into the layer of IMD. A barrier layer is blanket deposited, a copper seed layer is deposited over the barrier layer. The dual damascene structure is then filled with a spin-on material. The barrier layer and the copper seed layer are removed above the cap layer; the cap layer can be partially removed or can be left in place. The spin on material remains in place in the via and trench opening during the operation of removing the copper seed layer and the barrier layer from above the cap surface thereby protecting the inside surfaces of these openings. The spin-on material is next removed from the dual damascene structure and copper is deposited.
    Type: Grant
    Filed: September 7, 1999
    Date of Patent: February 6, 2001
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Paul Kwok Keung Ho, Mei Sheng Zhou, Subhash Gupta
  • Patent number: 6172421
    Abstract: The present invention relates to the formation of a protective intermetallic layer 15 on the surface of damascene metal interconnects 12 during semiconductor fabrication. The intermetallic layer 15 prevents problems associated with formation of an oxide layer on the surface of the interconnect. The intermetallic layer is formed by depositing a metal on the surface of the interconnect that will both reduce any present metal oxide layer and form an intermetallic with the interconnect metal.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: January 9, 2001
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Paul Raymond Besser, Shekhar Pramanick, Takeshi Nogami, Subhash Gupta
  • Patent number: 6132521
    Abstract: A method of cleaning elemental copper, cobalt, or nickel from the surface of equipment hardware without corroding or damaging the equipment parts and surfaces in the event of wafer breakage and non-wafer breakage is described. A solution includes an alkyldione peroxide, a stabilizing agent, and alcohols is used to oxidize the metal and form soluble complexes which are removed by the cleaning solution. Also, a alkyldione peroxide solution for cleaning elemental copper, cobalt, or nickel from the surface of equipment hardware in the event of wafer breakage and non-wafer breakage is provided.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: October 17, 2000
    Assignee: Chartered Semiconductor Manufacturing Ltd.
    Inventors: Subhash Gupta, Simon Chooi, Mei Sheng Zhou, Paul Ho
  • Patent number: 6114243
    Abstract: A new method to prevent copper contamination of the intermetal dielectric layer during via or dual damascene etching by forming a capping layer over the first copper metallization is described. A first copper metallization is formed in a dielectric layer overlying a semiconductor substrate wherein a barrier metal layer is formed underlying the first copper metallization and overlying the dielectric layer. The first copper metallization is planarized, then etched to form a recess below the surface of the dielectric layer. A conductive capping layer is deposited overlying the first copper metallization within the recess and overlying the dielectric layer. The conductive capping layer is removed except over the first copper metallization within the recess using one of several methods. An intermetal dielectric layer is deposited overlying the dielectric layer and the conductive capping layer overlying the first copper metallization.
    Type: Grant
    Filed: November 15, 1999
    Date of Patent: September 5, 2000
    Assignee: Chartered Semiconductor Manufacturing Ltd
    Inventors: Subhash Gupta, Kwok Keung Paul Ho, Mei-Sheng Zhou, Simon Chool
  • Patent number: 6106286
    Abstract: A dental loop for delivering Coenzyme Q10 to the periodontium by direct physical contact therewith, and a method using such loop. The loop is a loop of plain gut defining a series of pockets for carrying a medicament. Coenzyme Q10 is placed within the pockets, so that it is available directly at the site to which said loop is applied. The loop is slipped over a tooth and placed against the periodontium, and left in place for sufficient time for the Q10 to dissolve and act, and the loop dissolve.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: August 22, 2000
    Inventor: Subhash Gupta
  • Patent number: 6071824
    Abstract: A method and system for patterning a metal layer of a semiconductor device is disclosed. The method and system includes providing a material with an antireflective low dielectric constant hard mask layer (antireflective low k hard mask layer) on top of the metal layer, and providing a photoresist pattern on top of the anti-reflective low k hard mask layer. The method and system further includes etching of the anti-reflective low k hard mask layer and etching of the metal layer, wherein the photoresist is removed but the anti-reflective low k hard mask layer remains. In a preferred embodiment, the mask layer can also be applied at low temperatures (i.e., >300.degree.) to ensure that the physical properties of the integrated circuit are not affected. Finally, the low k material does not have to be removed after processing.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: June 6, 2000
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Bhanwar Singh, Subhash Gupta, Mutya Vicente, Susan Hsuching Chen
  • Patent number: 6066578
    Abstract: A system and method for forming a plurality of structures in a low dielectric constant layer is disclosed. The low dielectric constant layer is disposed on a semiconductor. The method and system include exposing the low dielectric constant layer to an agent that improves adhesion of a photoresist, providing a layer of the photoresist on the low dielectric constant layer, patterning the photoresist, and etching the low dielectric constant layer to form the plurality of structures.
    Type: Grant
    Filed: December 1, 1997
    Date of Patent: May 23, 2000
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Subhash Gupta, Bhanwar Singh, Carmen Morales
  • Patent number: 6051882
    Abstract: A method of fabricating an interconnection level of conductive lines and connecting vias separated by insulation for integrated circuits and substrate carriers for semiconductor devices using a reverse damascene in the formation of the conductive lines and vias. A conductive line pattern is first used to etch completely through the layer to form conductive line openings. The openings are completely filled with a conductive material and planarized so that the surfaces of the conductive material and the insulating layer are coplanar. A via pattern is aligned perpendicular to the conductive lines and the conductive material is etched half way through the conductive lines in other than the areas covered by the via pattern. The openings thus created in the upper portion of the conductive lines are filled with insulating material to complete the dual damascene interconnection level with the conductive lines in the lower portion of the insulating layer and upwardly projecting vias in the upper portion of the layer.
    Type: Grant
    Filed: August 5, 1997
    Date of Patent: April 18, 2000
    Assignee: Advanced Micro Devices
    Inventors: Steven Avanzino, Subhash Gupta, Rich Klein, Scott D. Luning, Ming-Rin Lin
  • Patent number: 6040619
    Abstract: A microelectronic device such as a Metal-Oxide-Semiconductor (MOS) transistor is formed on a semiconductor substrate. A tungsten damascene interconnect for the device is formed using an etch stop layer of silicon nitride, silicon oxynitride or silicon oxime having a high silicon content of approximately 40% to 50% by weight. The etch stop layer has high etch selectivity relative to overlying insulator materials such as silicon dioxide, tetraethylorthosilicate (TEOS) glass and borophosphosilicate glass (BPSG). The etch stop layer also has a high index of refraction and is anti-reflective, thereby improving critical dimension control during photolithographic imaging.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: March 21, 2000
    Assignee: Advanced Micro Devices
    Inventors: Fei Wang, David K. Foote, Myron R. Cagan, Subhash Gupta
  • Patent number: 5994206
    Abstract: A method and system for providing a via structure for a high conductivity metal of a integrated circuit is disclosed. In a first aspect the method and system comprises etching a photoresist material and a dielectric material down to the high conductivity metal to form a via hole. The via hole includes sputtered high conductivity metal on the sidewalls. The method and system further includes providing a via plug material within the via hole. The vial plug material substantially covers a base portion of the high conductivity metal and the sidewalls of the via hole. The via plug material is also capable of gettering or dissolving the high conductivity metal sputtered on the sidewalls of the dielectric material. In a second aspect, a via structure for an integrated circuit is disclosed in accordance with the present invention. The via structure includes a high conductivity metal and a dielectric material surrounding the high conductivity metal.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: November 30, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Subhash Gupta, Susan Hsuching Chen
  • Patent number: 5936307
    Abstract: A method for reducing stress in a TiN layer of a metallization structure, and a silicon wafer portion made by this method. The surface of the dielectric under the TiN is roughened using a water polish with a hard pad, to provide micromounts and valleys on the dielectric surface.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: August 10, 1999
    Assignee: Advanced Micro Devices, inc.
    Inventors: Diana M. Schonauer, Subhash Gupta, Paul Besser, Bhanwar Singh
  • Patent number: 5926690
    Abstract: It has been discovered that all causes of critical dimension variation, both known and unknown, are compensated by adjusting the time of photoresist etch. Accordingly, a control method employs a control system using photoresist etch time as a manipulated variable in either a feedforward or a feedback control configuration to control critical dimension variation during semiconductor fabrication. By controlling critical dimensions through the adjustment of photoresist etch time, many advantages are achieved including a reduced lot-to-lot variation, an increased yield, and increased speed of the fabricated circuits. In one embodiment these advantages are achieved for polysilicon gate critical dimension control in microprocessor circuits. Polysilicon gate linewidth variability is reduced using a control method using either feedforward and feedback or feedback alone. In some embodiments, feedback control is implemented for controlling critical dimensions using photoresist etch time as a manipulated variable.
    Type: Grant
    Filed: May 28, 1997
    Date of Patent: July 20, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Anthony John Toprac, Douglas John Downey, Subhash Gupta
  • Patent number: 5910453
    Abstract: An etching process for DUV photolithography is provided for etching a layer of anti-reflection coating (ARC) comprising spin-on organic ARC material which is formed beneath a layer of photoresist. After patterning the layer of photoresist, the layer of ARC is etched by employing a mixture of oxygen plasma, nitrogen plasma, and at least one inert gas. Anisotropic etching of the layer of ARC is provided with the process of the present invention. In comparison with prior art etching processes for etching a layer of ARC, the process of the present invention provides a favorable etch rate with improved selectivity over the etching of the layer of photoresist. The layer of ARC is etched without causing lateral erosion of the layer of photoresist. Faceting of the top edges of the corners of the layer of photoresist is also minimized. The profile of the layer of photoresist is essentially maintained thereby enabling for critical dimension fidelity.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: June 8, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Subhash Gupta, Mutya Vicente
  • Patent number: 5841196
    Abstract: A method of forming a via in a interlevel dielectric of a semiconductor device wherein the via has a fluted sidewall. A semiconductor substrate is provided having a first conductive layer formed thereon. A dielectric layer is then formed on the first conductive layer. A photoresist layer is deposited on a dielectric layer and a contact opening is formed in the photoresist layer to expose a contact region of the dielectric layer. A first etch step is performed to remove portions of the dielectric layer proximal to the contact region to form a first stage of the fluted via. The first stage includes a first sidewall stage extending from an upper surface of the dielectric layer at an angle less than 50.degree.. The first stage of the fluted via exterds a first lateral distance which is greater than a lateral dimension of the contact opening. A second etch step is then performed to further remove portions of the dielectric layer to form a second stage of the fluted via.
    Type: Grant
    Filed: November 14, 1997
    Date of Patent: November 24, 1998
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Subhash Gupta, Robert Flores, Michael Ross Stamm, Eric Thomas Sharp, Erich W. E. Denninger, Pamela G. Dye, Joel Samuel Utz, James K. Kai
  • Patent number: 5814560
    Abstract: A method is provided for forming metal interconnect structures which resists the formation of pile-ups caused by electromigration. Each metal interconnect structure includes an aluminum interconnect sandwiched between two refractory metal layers. The method of the present invention involves forming a layer of aluminum intermetallic alloy on the sidewalls of the aluminum interconnects. The layer of aluminum intermetallic alloy provides reinforcement for the sidewalls. The layer of aluminum intermetallic alloy comprises aluminum-refractory metal alloy. The aluminum-refractory metal alloy is formed by reacting the exposed aluminum on the sidewalls with refractory metal-containing precursor material. After the formation of the layer of aluminum intermetallic alloy the sidewalls of the aluminum interconnects, the formation of pile-ups will be suppressed. Thus, the lifetime of the aluminum interconnects is extended.
    Type: Grant
    Filed: November 29, 1995
    Date of Patent: September 29, 1998
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Robin W. Cheung, Simon S. Chan, Subhash Gupta
  • Patent number: 5795823
    Abstract: A method of fabricating an interconnection level of conductive lines and connecting vias separated by insulation for integrated circuits and substrate carriers for semiconductor devices using dual damascene with only one mask pattern for the formation of both the conductive lines and vias. The mask pattern of conductive lines contains laterally enlarged areas where the via openings are to formed in the insulating material. After the conductive line openings with laterally enlarged areas are created, the openings are filled with a conformal material whose etch selectivity is substantially less than the etch selectivity of the insulating material to the enchant for etching the insulating material and whose etch selectivity is substantially greater than the insulating material to its enchant. The conformal material is anisotropically etched to form sidewalls in the enlarged area and remove the material between the sidewalls but leave material remaining in the parts of the conductive lines openings.
    Type: Grant
    Filed: November 20, 1996
    Date of Patent: August 18, 1998
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Steven Avanzino, Subhash Gupta, Rich Klein, Scott D. Luning, Ming-Ren Lin
  • Patent number: 5770519
    Abstract: A multilayer semiconductor structure includes a conductive via. The conductive via includes a reservoir of metal having a high resistance to electromigration. The reservoir is made from a conformal layer of copper, or gold deposited over the via to form a copper, or gold plug located in the via. A barrier layer is provided between the reservoir and an insulating layer to prevent the reservoir from diffusing into the insulating layer. The barrier layer and reservoir may be deposited by sputtering, collimated sputtering, chemical vapor deposition (CVD), dipping, evaporating, or by other means. The barrier layer and reservoir may be etched by anisotropic dry etching, plasma-assisted etching, or other layer removal techniques.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: June 23, 1998
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Richard K. Klein, Darrell Erb, Steven Avanzino, Robin Cheung, Scott Luning, Bryan Tracy, Subhash Gupta, Ming-Ren Lin
  • Patent number: 5746884
    Abstract: A method of forming a via in a interlevel dielectric of a semiconductor device wherein the via has a fluted sidewall. A semiconductor substrate is provided having a first conductive layer formed thereon. A dielectric layer is then formed on the first conductive layer. A photoresist layer is deposited on a dielectric layer and a contact opening is formed in the photoresist layer to expose a contact region of the dielectric layer. A first etch step is performed to remove portions of the dielectric layer proximal to the contact region to form a first stage of the fluted via. The first stage includes a first sidewall stage extending from an upper surface of the dielectric layer at an angle less than 50.degree.. The first stage of the fluted via extends a first lateral distance which is greater than a lateral dimension of the contact opening. A second etch step is then performed to further remove portions of the dielectric layer to form a second stage of the fluted via.
    Type: Grant
    Filed: August 13, 1996
    Date of Patent: May 5, 1998
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Subhash Gupta, Robert Flores, Michael Ross Stamm, Eric Thomas Sharp, Erich W. E. Denninger, Pamela G. Dye, Joel Samuel Utz, James K. Kai
  • Patent number: D394705
    Type: Grant
    Filed: May 2, 1997
    Date of Patent: May 26, 1998
    Assignee: Everfresh, Inc.
    Inventor: Subhash Gupta