Patents by Inventor S. M. Reza Sadjadi

S. M. Reza Sadjadi 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: 20030087531
    Abstract: A system and method for achieving a silicon carbide to low-k dielectric etch selectivity ratio of greater than 1:1 using a chlorine containing gas and either hydrogen (H2) gas or nitrogen (N2) gas is described. The method is applied to a semiconductor substrate having a low-k dielectric layer and a silicon carbide layer. The chlorine containing gas is a gas mixture that includes either HCl, BCl3, Cl2, or any combination thereof. In one embodiment, the method provides for supplying an etchant gas comprising a chlorine containing gas and a hydrogen (H2) gas. The etchant gas is then energized to generate a plasma which then etches openings in the silicon carbide at a faster etch rate than the low-k dielectric etch rate. In an alternative embodiment, the etchant gas mixture comprises a chlorine containing gas and a nitrogen (N2) gas.
    Type: Application
    Filed: July 19, 2002
    Publication date: May 8, 2003
    Applicant: Lam Research Corporation
    Inventors: Sean S. Kang, Si Yi Li, S.M. Reza Sadjadi
  • Publication number: 20030024902
    Abstract: A semiconductor manufacturing process wherein a low-k dielectric layer is plasma etched with selectivity to an overlying mask layer. The etchant gas can be oxygen-free and include a fluorocarbon reactant, a nitrogen reactant and an optional carrier gas, the fluorocarbon reactant and nitrogen reactant being supplied to a chamber of a plasma etch reactor at flow rates such that the fluorocarbon reactant flow rate is less than the nitrogen reactant flow rate. The etch rate of the low-k dielectric layer can be at least 5 times higher than that of a silicon dioxide, silicon nitride, silicon oxynitride or silicon carbide mask layer. The process is useful for etching 0.25 micron and smaller contact or via openings in forming structures such as damascene structures.
    Type: Application
    Filed: March 30, 2001
    Publication date: February 6, 2003
    Inventors: Si Yi Li, Helen H. Zhu, S. M. Reza Sadjadi, James V. Tietz, Bryan A. Helmer
  • Patent number: 6495470
    Abstract: A method of forming a contact opening between two conductive features over a semiconductor substrate. Oxide spacers are formed adjacent to the conductive features. A doped oxide layer is then deposited over the semiconductor substrate. Finally, the contact opening is etched through the doped oxide layer between the conductive features such that the oxide spacers are exposed within the contact opening.
    Type: Grant
    Filed: December 29, 1995
    Date of Patent: December 17, 2002
    Assignee: Intel Corporation
    Inventors: S. M. Reza Sadjadi, Mansour Moinpour, Te Hua Lin, Farhad K. Moghadam
  • Publication number: 20020182880
    Abstract: A semiconductor manufacturing process wherein silicon nitride is plasma etched with selectivity to an overlying and/or underlying dielectric layer such as a silicon oxide or low-k material. The etchant gas includes a fluorocarbon reactant and an oxygen reactant, the ratio of the flow rate of the oxygen reactant to that of the fluorocarbon reactant being no greater than 1.5. The etch rate of the silicon nitride can be at least 5 times higher than that of the oxide. Using a combination of CH3F and O2 with optional carrier gasses such as Ar and/or N2, it is possible to obtain nitride:oxide etch rate selectivities of over 40:1. The process is useful for simultaneously removing silicon nitride in 0.25 micron and smaller contact or via openings and wide trenches in forming structures such as damascene and self-aligned structures.
    Type: Application
    Filed: March 30, 2001
    Publication date: December 5, 2002
    Inventors: Helen H. Zhu, David R. Pirkle, S.M. Reza Sadjadi, Andrew S. Li
  • Publication number: 20020177322
    Abstract: The invention provides a process for plasma etching silicon carbide with selectivity to an overlapping and/or underlying dielectric layer of material. The etching gas includes a hydrogen-containing fluorocarbon gas such as CH3F, an oxygen-containing gas such as O2 and an optional carrier gas such as Ar. The dielectric material can comprise silicon dioxide, silicon nitride, silicon oxynitride or various low-k dielectric materials including organic low-k materials. In order to achieve a desired selectivity to such dielectric materials, the plasma etch gas chemistry is selected to achieve a desired etch rate of the silicon carbide while etching the dielectric material at a slower rate. The process can be used to selectively etch a hydrogenated silicon carbide etch stop layer or silicon carbide substrates.
    Type: Application
    Filed: March 30, 2001
    Publication date: November 28, 2002
    Inventors: Si Yi Li, Helen H. Zhu, S.M. Reza Sadjadi, David R. Pirkle, James Bowers, Michael Goss
  • Publication number: 20020031901
    Abstract: A method of forming a contact opening between two conductive features over a semiconductor substrate. Oxide spacers are formed adjacent to the conductive features. A doped oxide layer is then deposited over the semiconductor substrate. Finally, the contact opening is etched through the doped oxide layer between the conductive features such that the oxide spacers are exposed within the contact opening.
    Type: Application
    Filed: December 29, 1995
    Publication date: March 14, 2002
    Inventors: S.M. REZA SADJADI, MANSOUR MOINPOUR, TE H. LIN, FARHAD K. MOGHADAM
  • Patent number: 5883436
    Abstract: A method of forming a contact opening between two conductive features over a semiconductor substrate. Oxide spacers are formed adjacent to the conductive features. A doped oxide layer is then deposited over the semiconductor substrate. Finally, the contact opening is etched through the doped oxide layer between the conductive features such that the oxide spacers are exposed within the contact opening.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: March 16, 1999
    Assignee: Intel Corporation
    Inventors: S. M. Reza Sadjadi, Mansour Moinpour, Te Hua Lin, Farhad K. Moghadam
  • Patent number: 5705419
    Abstract: In the manufacture of memory cells, horizontal etching is controlled in a manner which prevents the formation of stringers between adjacent cells without undercutting the sidewalls of a memory cell.
    Type: Grant
    Filed: July 27, 1994
    Date of Patent: January 6, 1998
    Assignee: National Semiconductor Corp.
    Inventors: Jeffrey Robert Perry, S. M. Reza Sadjadi, Kristen Ann Luttinger
  • Patent number: 5427967
    Abstract: There is disclosed herein a technique for manufacturing a group of memory cells or devices on a common oxide coated silicon substrate such that the cells are arranged in rows and columns with row and column spaces separating the individual cells from one another. Each of the cells includes an array of different layers on the oxide coated top surface of the substrate including, in particular, the polysilicon layer. As disclosed, a method is provided for preventing the formation of polysilicon stringers between individual cells during their manufacture. This method is carried out by first forming the columns before the rows are formed such that continuous sidewalls of the columns are exposed to the ambient surroundings. Thereafter, these sidewalls are coated with protective layers, specifically layers of nitride.
    Type: Grant
    Filed: March 11, 1993
    Date of Patent: June 27, 1995
    Assignee: National Semiconductor Corporation
    Inventors: S. M. Reza Sadjadi, Jeffrey R. Perry
  • Patent number: 5383018
    Abstract: A calibration wafer for a patterned wafer scanner is constructed from a substrate of semiconductor material, typically silicon, in which a pattern of features has been etched into the periphery of each die by means of photolithographic techniques. Next, a layer or layers of films composed of materials which are typically used during the fabrication of integrated circuits are deposited. Then a substantially uniform distribution of particles of a known material and size distribution is deposited onto the wafer. A second embodiment of the calibration wafer is one in which a layer or layers of film are first deposited onto a substrate. Then a pattern of features is etched into the periphery of the film covering each die by means of photolithographic techniques. After this step, a substantially uniform distribution of particles is deposited. A method of using such a calibration wafer to calibrate a patterned wafer scanner is also disclosed.
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: January 17, 1995
    Assignee: National Semiconductor Corporation
    Inventor: S. M. Reza Sadjadi
  • Patent number: 5342801
    Abstract: In the manufacture of memory cells, horizontal etching is controlled in a manner which prevents the formation of stringers between adjacent cells without undercutting the sidewalls of a memory cell.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: August 30, 1994
    Assignee: National Semiconductor Corporation
    Inventors: Jeffrey R. Perry, S. M. Reza Sadjadi, Kristen A. Luttinger