Patents by Inventor Ruggero Castagnetti

Ruggero Castagnetti 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: 6586291
    Abstract: A memory cell having a transistor and a capacitor formed in a silicon substrate. The capacitor is formed with a lower electrically conductive plate etched in a projected surface area of the silicon substrate. The lower electrically conductive plate has at least one cross section in the shape of a vee, where the sides of the vee are disposed at an angle of about fifty-five degrees from a top surface of the silicon substrate. The surface area of the lower electrically conductive plate is about seventy-three percent larger than the projected surface area of the silicon substrate in which the lower electrically conductive plate is etched. A capacitor dielectric layer is formed of a first deposited dielectric layer, which is disposed adjacent the lower electrically conductive plate. A top electrically conductive plate is disposed adjacent the capacitor dielectric layer and opposite the lower electrically conductive plate.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: July 1, 2003
    Assignee: LSI Logic Corporation
    Inventors: Arvind Kamath, Ruggero Castagnetti
  • Patent number: 6566171
    Abstract: Fuses, and optionally metal pads, are formed over a layer of low k dielectric material structure having first openings lined with conductive barrier material and filled to form metal interconnects in the upper surface of the low k dielectric material. A dielectric layer is formed over the low k dielectric material and over the metal interconnects, and patterned to form second openings therein communicating with the metal interconnects. A conductive barrier layer is formed over this dielectric layer in contact with the metal interconnects, and patterned to form fuse portions between some of the metal interconnects, and a liner over one or more of the metal interconnects. A dielectric layer is then formed over the patterned conductive barrier layer to form a window above each fuse, and patterned to form openings over at least some of the conductive barrier liners filled with metal to form metal pads.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: May 20, 2003
    Assignee: LSI Logic Corporation
    Inventors: Yauh-Ching Liu, Ruggero Castagnetti, Ramnath Venkatraman
  • Patent number: 6566730
    Abstract: A severable horizontal portion of a fuse link is formed relative to a vertically configured structure in an IC to promote separation of the severable portion upon applying energy from a laser beam. The vertically configured structure may be a reduced vertical thickness of the severable portion, an elevated lower surface of the severable portion above adjoining portions of the fuse link, a protrusion which supports the severable portion at a height greater than a height of the adjoining portions of the fuse link, flowing the melted severable portion down sloped surfaces away from a break point, and a propellent material beneath the severable portion which explodes to ablate the severable portion.
    Type: Grant
    Filed: November 27, 2000
    Date of Patent: May 20, 2003
    Assignee: LSI Logic Corporation
    Inventors: Gary K. Giust, Ruggero Castagnetti, Yauh-Ching Liu, Shiva Ramesh
  • Patent number: 6472715
    Abstract: An integrated circuit structures such as an SRAM construction wherein the soft error rate is reduced comprises an integrated circuit structure formed in a semiconductor substrate, wherein at least one N channel transistor is built in a P well adjacent to one or more deep N wells connected to the high voltage supply and the deep N wells extend from the surface of the substrate down into the substrate to a depth at least equal to that depth at which alpha particle-generated electron-hole pairs can effectively cause a soft error in the SRAM cell. For a 0.25 &mgr;m SRAM design having one or more N wells of a conventional depth not exceeding about 0.5 &mgr;m, the depth at which alpha particle-generated electron-hole pairs can effectively cause a soft error in the SRAM cell is from 1 to 3 &mgr;m. The deep N well of the 0.25 &mgr;m SRAM design, therefore, extends down from the substrate surface a distance of at least about 1 &mgr;m, and preferably at least about 2 &mgr;m.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: October 29, 2002
    Assignee: LSI Logic Corporation
    Inventors: Yauh-Ching Liu, Helmut Puchner, Ruggero Castagnetti, Weiran Kong, Lee Phan, Franklin Duan, Steven Michael Peterson
  • Patent number: 6442061
    Abstract: A method of forming a memory cell according to the present invention. A first pass gate transistor is formed of a first transistor type. The first pass gate transistor has a gate oxide with a first thickness. The source of the first pass gate transistor is electrically connected to a first bit line, and the drain of the first pass gate transistor is electrically connected to a first state node. The gate of the first pass gate transistor is electrically connected to a memory cell enable line. A second pass gate transistor is also formed of the first transistor type. The second pass gate transistor also has a gate oxide with the first thickness. The source of the second pass gate transistor is electrically connected to a second bit line, and the drain of the second pass gate transistor is electrically connected to a second state node. The gate of the second pass gate transistor is electrically connected to the memory cell enable line. A first state node transistor is also formed of the first transistor type.
    Type: Grant
    Filed: February 14, 2001
    Date of Patent: August 27, 2002
    Assignee: LSI Logic Corporation
    Inventors: Weiran Kong, Gary K. Giust, Ramnath Venkatraman, Yauh-Ching Liu, Franklin Duan, Ruggero Castagnetti, Steven M. Peterson, Myron J. Buer, Minh Tien Nguyen
  • Patent number: 6413848
    Abstract: Provided are a self-aligned semiconductor fuse structure, a method of making such a fuse structure, and apparatuses incorporating such a fuse structure. The fuse break point, that point at which the electrical link of which the fuse is part is severed by a laser beam, is self-aligned by the use of photolithographically patterned anti-reflective dielectric coatings. The self-alignment allows the size location of the break point to be less sensitive to the laser beam size and alignment. This has several advantages including allowing photolithographic control and effective size reduction of the laser spot irradiating the fuse material and surrounding structure. This permits reduced fuse pitch, increasing density and the efficiency of use of chip area, and results in reduced thermal exposure, which causes less damage to chip. In addition, laser alignment is less critical and therefore less timely, which increases throughput in fabrication.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: July 2, 2002
    Assignee: LSI Logic Corporation
    Inventors: Gary K. Giust, Ruggero Castagnetti, Yauh-Ching Liu, Subramanian Ramesh
  • Patent number: 6259146
    Abstract: Provided are a self-aligned semiconductor fuse structure, a method of making such a fuse structure, and apparatuses incorporating such a fuse structure. The fuse break point, that point at which the electrical link of which the fuse is part is severed by a laser beam, is self-aligned by the use of photolithographically patterned dielectric and a heat sink material. The self-alignment allows the size and location of the break point to be more forgiving of the laser beam size and alignment. This has several advantages, including allowing photolithographic control and effective size reduction of the laser spot irradiating the fuse material and surrounding structure. This permits reduced fuse pitch, increasing density and the efficiency of use of chip area, and results in reduced thermal exposure, which causes less damage to chip. In addition, laser alignment is less critical and therefore less time-consuming, which increases throughput in fabrication.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: July 10, 2001
    Assignee: LSI Logic Corporation
    Inventors: Gary K. Giust, Ruggero Castagnetti, Yauh-Ching Liu, Subramanian Ramesh
  • Patent number: 6218276
    Abstract: Provided is a method of forming a silicide layer on the top and sidewall surfaces of a polysilicon gate/interconnect in a MOS transistor and on the exposed surfaces of the source and drain regions of the transistor. Devices produced according to the present invention may have different types of silicide formed on their gate and their source/drain electrodes. The invention achieves the advantages of silicide encapsulation of a polysilicon gate in an MOS transistor while also providing silicidation of the source/drain regions of the transistor, thereby reducing electrode resistivity in the transistor and interconnect.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: April 17, 2001
    Assignee: LSI Logic Corporation
    Inventors: Yauh-Ching Liu, Gary K. Giust, Ruggero Castagnetti, Subramanian Ramesh
  • Patent number: 6166403
    Abstract: An integrated circuit including a substrate having a memory area and a non-memory area. An embedded memory is fabricated on the substrate within the memory area. First and second semiconductor cells are fabricated on the substrate within the non-memory area. An electromagnetic shield covers substantially memory area. A routing layer is fabricated over the memory and non-memory areas and over the electromagnetic shield. A signal wire is electrically coupled between the first and second semiconductor cells and has a conductive segment which is routed within the routing layer and extends over the memory area.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: December 26, 2000
    Assignee: LSI Logic Corporation
    Inventors: Ruggero Castagnetti, Yauh-Ching Liu, Subramanian Ramesh
  • Patent number: 6162714
    Abstract: A method is provided for forming thin polysilicon transistor gates using dual doped polysilicon without reducing the ion implant energy. The method comprises depositing polysilicon over a region of a substrate, masking and implanting the polysilicon with dopant impurities to form the channel regions of one conductivity type, and removing the photo resist mask. The polysilicon layer is then masked to define the channel regions of the opposite conductivity type and is implanted with dopant impurities of the opposite conductivity type. Following the dual ion implantation, the photo resist mask is removed and the substrate may be annealed to activate the dopants in the polysilicon. The dual doped polysilicon layer is then polished using a chemical-mechanical polish to achieve a desired thickness for the polysilicon transistor gates. The polysilicon is subsequently masked and etched to define the polysilicon transistor gates.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: December 19, 2000
    Assignee: LSI Logic Corporation
    Inventors: Ruggero Castagnetti, Yauh-Ching Liu, Gary Giust, Subramanian Ramesh
  • Patent number: 6144076
    Abstract: A multiple well formation is provided in a CMOS region of a semiconductor substrate to provide enhanced latchup protection for one or more CMOS transistors formed in the wells. The structure comprises an N well extending from the substrate surface down into the substrate, a buried P well formed in the substrate beneath the N well, a second P well extending from the substrate surface down into the substrate, and an isolation region formed in the substrate between the N well and the second P well. The buried P well may extend beneath both the N well and the second P well in the substrate. In a preferred embodiment of the invention, the N well and the second P well are each implanted in the substrate at an energy level sufficient to provide a dopant concentration peak in the substrate below the depth of the isolation region to provide punch through protection and to provide a channel stop beneath the isolation region by proving a P-N junction between the N well and P well beneath the isolation region.
    Type: Grant
    Filed: December 8, 1998
    Date of Patent: November 7, 2000
    Assignee: LSI Logic Corporation
    Inventors: Helmut Puchner, Shih-Fen Huang, Ruggero Castagnetti
  • Patent number: 6066525
    Abstract: Disclosed are planar DRAM cells including a storage capacitor having a high dielectric constant capacitor dielectric. The DRAM cell also includes an access transistor having a gate dielectric which does not include the high dielectric constant material. A single polysilicon layer is employed to form the gate electrode of the access transistor and a reference plate of the storage capacitor. A disclosed fabrication process forms the high dielectric constant material that is limited to a capacitor region of the DRAM cell and then forms the gate dielectric over an entire active region including both the high dielectric constant material layer at the capacitor region and the semiconductor substrate at the access transistor region. In this manner, a high quality gate dielectric (e.g., silicon oxide) is formed at the access transistor region and a high dielectric constant dielectric layer (e.g., silicon nitride) is formed at the capacitor region.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: May 23, 2000
    Assignee: LSI Logic Corporation
    Inventors: Yauh-Ching Liu, Ruggero Castagnetti, Subramanian Ramesh
  • Patent number: 6061264
    Abstract: Provided are a self-aligned semiconductor fuse structure, a method of making such a fuse structure, and apparatuses incorporating such a fuse structure. The fuse break point, that point at which the electrical link of which the fuse is part is severed by a laser beam, is self-aligned by the use of photolithography and an anti-reflective coating. The self-alignment allows the size and location of the break point to be less sensitive to the laser beam size and alignment. This has several advantages, including allowing photolithographic control and effective size reduction of the laser spot irradiating the fuse material and surrounding structure. This permits reduced fuse pitch, increasing density and the efficiency of use of chip area, and results in reduced thermal exposure, which causes less damage to chip. In addition, laser alignment is less critical and therefore less time-consuming, which increases throughput in fabrication.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: May 9, 2000
    Assignee: LSI Logic Corporation
    Inventors: Gary K. Giust, Ruggero Castagnetti, Yauh-Ching Liu, Subramanian Ramesh
  • Patent number: 6037233
    Abstract: Provided are methods of forming a metal layer on the horizontal and vertical surfaces of a polysilicon gate electrode/interconnect in a MOS transistor, and devices having metal-encapsulated gates and interconnects. The metal encapsulation method of the present invention may also provide a layer of metal on the exposed surfaces of the source and drain regions of the transistor. The methods and apparatuses of the present invention allow reductions in device resistance and signal propagation delays.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: March 14, 2000
    Assignee: LSI Logic Corporation
    Inventors: Yauh-Ching Liu, Gary K. Giust, Ruggero Castagnetti, Subramanian Ramesh
  • Patent number: 5953614
    Abstract: A process is described for forming self-aligned contacts to an MOS device on an integrated circuit structure characterized by the simultaneous formation of the metal silicide gate portion and the metal silicide source/drain portions. The process comprises forming a gate oxide layer on a silicon substrate, forming a polysilicon gate electrode layer over the gate oxide layer, and forming a layer of a first insulation material over the polysilicon gate electrode layer. Metal silicide is simultaneously formed on the exposed surface of the polysilicon gate electrode and over the exposed portions of the silicon substrate. Source/drain regions are formed in the silicon substrate, either before or after formation of the metal silicide over the exposed portions of the silicon substrate, whereby the metal silicide portions on the substrate above the source/drain regions are in electrical communication with the source/drain regions.
    Type: Grant
    Filed: October 9, 1997
    Date of Patent: September 14, 1999
    Assignee: LSI Logic Corporation
    Inventors: Yauh-Ching Liu, Gary K. Giust, Ruggero Castagnetti, Subramanian Ramesh