Patents by Inventor Suresh Venkatesan

Suresh Venkatesan 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: 7078297
    Abstract: A memory cell includes devices having associated isolation recesses of differing magnitudes. The effective channel width of a corresponding transistor is substantially equal to a channel top surface width plus twice a sidewall width formed by the isolation recesses. In an SRAM cell, a latch transistor has a larger effective channel width than an associated pass transistor by forming larger recesses, and therefore larger sidewalls in isolation layers surrounding the latch transistor and limiting such recesses for pass transistors. During manufacture of the memory cell, a mask is used to mask an area of the pass transistor while exposing an area of the latch transistor. Accordingly, recesses in an isolation layer around the latch transistor are formed without affecting a corresponding area around the pass transistor.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: July 18, 2006
    Assignee: Freescale Semiconductor, Inc.
    Inventors: James D. Burnett, Suresh Venkatesan
  • Publication number: 20060046366
    Abstract: A method and apparatus is presented that provides mobility enhancement in the channel region of a transistor. In one embodiment, a channel region (18) is formed over a substrate that is bi-axially stressed. Source (30) and drain (32) regions are formed over the substrate. The source and drain regions provide an additional uni-axial stress to the bi-axially stressed channel region. The uni-axial stress and the bi-axial stress are both compressive for P-channel transistors and both tensile for N-channel transistors. The result is that carrier mobility is enhanced for both short channel and long channel transistors. Both transistor types can be included on the same integrated circuit.
    Type: Application
    Filed: August 24, 2004
    Publication date: March 2, 2006
    Inventors: Marius Orlowski, Suresh Venkatesan
  • Publication number: 20050275018
    Abstract: A semiconductor device structure uses two semiconductor layers to separately optimize N and P channel transistor carrier mobility. The conduction characteristic for determining this is a combination of material type of the semiconductor, crystal plane, orientation, and strain. Hole mobility is improved in P channel transistors when the conduction characteristic is characterized by the semiconductor material being silicon germanium, the strain being compressive, the crystal plane being (100), and the orientation being <100>. In the alternative, the crystal plane can be (111) and the orientation in such case is unimportant. The preferred substrate for N-type conduction is different from the preferred (or optimum) substrate for P-type conduction. The N channel transistors preferably have tensile strain, silicon semiconductor material, and a (100) plane. With the separate semiconductor layers, both the N and P channel transistors can be optimized for carrier mobility.
    Type: Application
    Filed: June 10, 2004
    Publication date: December 15, 2005
    Inventors: Suresh Venkatesan, Mark Foisy, Michael Mendicino, Marius Orlowski
  • Publication number: 20050266643
    Abstract: A memory cell includes devices having associated isolation recesses of differing magnitudes. The effective channel width of a corresponding transistor is substantially equal to a channel top surface width plus twice a sidewall width formed by the isolation recesses. In an SRAM cell, a latch transistor has a larger effective channel width than an associated pass transistor by forming larger recesses, and therefore larger sidewalls in isolation layers surrounding the latch transistor and limiting such recesses for pass transistors. During manufacture of the memory cell, a mask is used to mask an area of the pass transistor while exposing an area of the latch transistor. Accordingly, recesses in an isolation layer around the latch transistor are formed without affecting a corresponding area around the pass transistor.
    Type: Application
    Filed: May 28, 2004
    Publication date: December 1, 2005
    Inventors: James Burnett, Suresh Venkatesan
  • Patent number: 6713381
    Abstract: An interconnect overlies a semiconductor device substrate (10). In one embodiment, a conductive barrier layer overlies a portion of the interconnect, a passivation layer (92) overlies the conductive barrier layer and the passivation layer (92) has an opening that exposes portions of the conductive barrier layer (82). In an alternate embodiment a passivation layer (22) overlies the interconnect, the passivation layer (22) has an opening (24) that exposes the interconnect and a conductive barrier layer (32) overlies the interconnect within the opening (24).
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: March 30, 2004
    Assignee: Motorola, Inc.
    Inventors: Alexander L. Barr, Suresh Venkatesan, David B. Clegg, Rebecca G. Cole, Olubunmi Adetutu, Stuart E. Greer, Brian G. Anthony, Ramnath Venkatraman, Gregor Braeckelmann, Douglas M. Reber, Stephen R. Crown
  • Publication number: 20040012037
    Abstract: High quality gallium arsenide (GaAs) (38) is grown over a thin germanium layer (26) and co-exists with silicon (40) for hetero-integration of devices. A bonded germanium wafer of silicon (22), oxide (24), and germanium (26) is formed and capped (30). The cap (30) and germanium layer (26) are partially removed so as to expose a silicon region (32) and leave a stack (31) of oxide, germanium, and capping layer on the silicon. Selective silicon is grown over the exposed silicon region. Silicon devices (36) are made in the selectively grown region of silicon (34). The remaining capping layer (30) is etched away to expose the thin layer of germanium (26). GaAs (38) is grown on the thin germanium layer (26), and GaAs devices (29) are built which can interoperate with the silicon devices (36). Alternatively, a smaller portion of the remaining cap (30) can be removed and germanium or silicon-germanium can be selectively grown on the exposed germanium (214) in order to form germanium or silicon-germanium devices (216).
    Type: Application
    Filed: July 18, 2002
    Publication date: January 22, 2004
    Applicant: MOTOROLA, INC.
    Inventors: Suresh Venkatesan, Papu D. Maniar
  • Patent number: 6573173
    Abstract: A copper interconnect polishing process begins by polishing (17) a bulk thickness of copper (63) using a first platen. A second platen is then used to remove (19) a thin remaining interfacial copper layer to expose a barrier film (61). Computer control (21) monitors polish times of the first and second platen and adjusts these times to improve wafer throughput. One or more platens and/or the wafer is rinsed (20) between the interfacial copper polish and the barrier polish to reduce slurry cross contamination. A third platen and slurry is then used to polish away exposed portions of the barrier (61) to complete polishing of the copper interconnect structure. A holding tank that contains anti-corrosive fluid is used to queue the wafers until subsequent scrubbing operations (25). A scrubbing operation (25) that is substantially void of light is used to reduce photovoltaic induced corrosion of copper in the drying chamber of the scubber.
    Type: Grant
    Filed: June 20, 2002
    Date of Patent: June 3, 2003
    Assignee: Motorola, Inc.
    Inventors: Janos Farkas, Brian G. Anthony, Abbas Guvenilir, Mohammed Rabiul Islam, Venkat Kolagunta, John Mendonca, Rajesh Tiwari, Suresh Venkatesan
  • Patent number: 6551919
    Abstract: A dual inlaid copper interconnect structure uses a plasma enhanced nitride (PEN) bottom capping layer and a silicon rich silicon oxynitride intermediate etch stop layer. The interfaces (16a, 16b, 20a, and 20b) between these layers (16 and 20) and their adjacent dielectric layers (18 and 22) are positioned in the stack (13) independent of the desired aspect ratio of trench openings of the copper interconnect in order to improve optical properties of the dielectric stack (13). Etch processing is then used to position the layers (16) and (20) at locations within the inlaid structure depth that result in one or more of reduced DC leakage current, improved optical performance, higher frequency of operation, reduced cross talk, increased flexibility of design, or like improvements.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: April 22, 2003
    Assignee: Motorola, Inc.
    Inventors: Suresh Venkatesan, Bradley P. Smith, Mohammed Rabiul Islam
  • Publication number: 20020151167
    Abstract: A copper interconnect polishing process begins by polishing (17) a bulk thickness of copper (63) using a first platen. A second platen is then used to remove (19) a thin remaining interfacial copper layer to expose a barrier film (61). Computer control (21) monitors polish times of the first and second platen and adjusts these times to improve wafer throughput. One or more platens and/or the wafer is rinsed (20) between the interfacial copper polish and the barrier polish to reduce slurry cross contamination. A third platen and slurry is then used to polish away exposed portions of the barrier (61) to complete polishing of the copper interconnect structure. A holding tank that contains anti-corrosive fluid is used to queue the wafers until subsequent scrubbing operations (25). A scrubbing operation (25) that is substantially void of light is used to reduce photovoltaic induced corrosion of copper in the drying chamber of the scubber.
    Type: Application
    Filed: June 20, 2002
    Publication date: October 17, 2002
    Inventors: Janos Farkas, Brian G. Anthony, Abbas Guvenilir, Mohammed Rabiul Islam, Venkat Kolagunta, John Mendonca, Rajesh Tiwari, Suresh Venkatesan
  • Patent number: 6444569
    Abstract: A copper interconnect polishing process begins by polishing (17) a bulk thickness of copper (63) using a first platen. A second platen is then used to remove (19) a thin remaining interfacial copper layer to expose a barrier film (61). Computer control (21) monitors polish times of the first and second platen and adjusts these times to improve wafer throughput. One or more platens and/or the wafer is rinsed (20) between the interfacial copper polish and the barrier polish to reduce slurry cross contamination. A third platen and slurry is then used to polish away exposed portions of the barrier (61) to complete polishing of the copper interconnect structure. A holding tank that contains anti-corrosive fluid is used to queue the wafers until subsequent scrubbing operations (25). A scrubbing operation (25) that is substantially void of light is used to reduce photovoltaic induced corrosion of copper in the drying chamber of the scubber.
    Type: Grant
    Filed: April 16, 2001
    Date of Patent: September 3, 2002
    Assignee: Motorola, Inc.
    Inventors: Janos Farkas, Brian G. Anthony, Abbas Guvenilir, Mohammed Rabiul Islam, Venkat Kolagunta, John Mendonca, Rajesh Tiwari, Suresh Venkatesan
  • Publication number: 20020093098
    Abstract: An interconnect overlies a semiconductor device substrate (10). In one embodiment, a conductive barrier layer overlies a portion of the interconnect, a passivation layer (92) overlies the conductive barrier layer and the passivation layer (92) has an opening that exposes portions of the conductive barrier layer (82). In an alternate embodiment a passivation layer (22) overlies the interconnect, the passivation layer (22) has an opening (24) that exposes the interconnect and a conductive barrier layer (32) overlies the interconnect within the opening (24).
    Type: Application
    Filed: January 18, 2002
    Publication date: July 18, 2002
    Inventors: Alexander L. Barr, Suresh Venkatesan, David B. Clegg, Rebecca G. Cole, Olubunmi Adetutu, Stuart E. Greer, Brian G. Anthony, Ramnath Venkatraman, Gregor Braeckelmann, Douglas M. Reber, Stephen R. Crown
  • Publication number: 20020039836
    Abstract: A dual inlaid copper interconnect structure uses a plasma enhanced nitride (PEN) bottom capping layer and a silicon rich silicon oxynitride intermediate etch stop layer. The interfaces (16a, 16b, 20a, and 20b) between these layers (16 and 20) and their adjacent dielectric layers (18 and 22) are positioned in the stack (13) independent of the desired aspect ratio of trench openings of the copper interconnect in order to improve optical properties of the dielectric stack (13). Etch processing is then used to position the layers (16) and (20) at locations within the inlaid structure depth that result in one or more of reduced DC leakage current, improved optical performance, higher frequency of operation, reduced cross talk, increased flexibility of design, or like improvements.
    Type: Application
    Filed: October 3, 2001
    Publication date: April 4, 2002
    Inventors: Suresh Venkatesan, Bradley P. Smith, Mohammed Rabiul Islam
  • Patent number: 6362057
    Abstract: A conductive layer (14) and a dummy feature (16) are formed over a semiconductor substrate (10) doped with a first dopant type. A spacer (42) is then formed adjacent the dummy feature (16) and is used to define a first patterned feature (92). In one embodiment, substrate regions (90) are doped with a second dopant type that is a same dopant type as the first dopant type. In an alternative embodiment, substrate regions (90) are doped with a second dopant type that is opposite the first dopant type. The dummy feature (16) is then removed and remaining portions of the spacer (100) are used to define a gate electrode (120). The substrate (10) is then doped optionally with a third dopant type and then with a fourth dopant type, the third and fourth dopant types being opposite the first dopant type, to form asymmetrically doped source (172) and drain regions (174) in the semiconductor substrate (10).
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: March 26, 2002
    Assignee: Motorola, Inc.
    Inventors: William J. Taylor, Jr., Suresh Venkatesan, Asanga H. Perera
  • Publication number: 20020000665
    Abstract: An interconnect overlies a semiconductor device substrate (10). In one embodiment, a conductive barrier layer overlies a portion of the interconnect, a passivation layer (92) overlies the conductive barrier layer and the passivation layer (92) has an opening that exposes portions of the conductive barrier layer (82). In an alternate embodiment a passivation layer (22) overlies the interconnect, the passivation layer (22) has an opening (24) that exposes the interconnect and a conductive barrier layer (32) overlies the interconnect within the opening (24).
    Type: Application
    Filed: April 5, 1999
    Publication date: January 3, 2002
    Inventors: ALEXANDER L. BARR, SURESH VENKATESAN, DAVID B. CLEGG, REBECCA G. COLE, OLUBUNMI ADETUTU, STUART E. GREER, BRIAN G. ANTHONY, RAMNATH VENKATRAMAN, GREGOR BRAECKELMANN, DOUGLAS M. REBER, STEPHEN R. CROWN
  • Patent number: 6326301
    Abstract: A dual inlaid copper interconnect structure uses a plasma enhanced nitride (PEN) bottom capping layer and a silicon rich silicon oxynitride intermediate etch stop layer. The interfaces (16a, 16b, 20a, and 20b) between these layers (16 and 20) and their adjacent dielectric layers (18 and 22) are positioned in the stack (13) independent of the desired aspect ratio of trench openings of the copper interconnect in order to improve optical properties of the dielectric stack (13). Etch processing is then used to position the layers (16) and (20) at locations within the inlaid structure depth that result in one or more of reduced DC leakage current, improved optical performance, higher frequency of operation, reduced cross talk, increased flexibility of design, or like improvements.
    Type: Grant
    Filed: July 13, 1999
    Date of Patent: December 4, 2001
    Assignee: Motorola, Inc.
    Inventors: Suresh Venkatesan, Bradley P. Smith, Mohammed Rabiul Islam
  • Publication number: 20010027083
    Abstract: A copper interconnect polishing process begins by polishing (17) a bulk thickness of copper (63) using a first platen. A second platen is then used to remove (19) a thin remaining interfacial copper layer to expose a barrier film (61). Computer control (21) monitors polish times of the first and second platen and adjusts these times to improve wafer throughput. One or more platens and/or the wafer is rinsed (20) between the interfacial copper polish and the barrier polish to reduce slurry cross contamination. A third platen and slurry is then used to polish away exposed portions of the barrier (61) to complete polishing of the copper interconnect structure. A holding tank that contains anti-corrosive fluid is used to queue the wafers until subsequent scrubbing operations (25). A scrubbing operation (25) that is substantially void of light is used to reduce photovoltaic induced corrosion of copper in the drying chamber of the scubber.
    Type: Application
    Filed: April 16, 2001
    Publication date: October 4, 2001
    Inventors: Janos Farkas, Brian G. Anthony, Abbas Guvenilir, Mohammed Rabiul Islam, Venkat Kolagunta, John Mendonca, Rajesh Tiwari, Suresh Venkatesan
  • Patent number: 6274478
    Abstract: A copper interconnect polishing process begins by polishing (17) a bulk thickness of copper (63) using a first platen. A second platen is then used to remove (19) a thin remaining interfacial copper layer to expose a barrier film (61). Computer control (21) monitors polish times of the first and second platen and adjusts these times to improve wafer throughput. One or more platens and/or the wafer is rinsed (20) between the interfacial copper polish and the barrier polish to reduce slurry cross contamination. A third platen and slurry is then used to polish away exposed portions of the barrier (61) to complete polishing of the copper interconnect structure. A holding tank that contains anti-corrosive fluid is used to queue the wafers until subsequent scrubbing operations (25). A scrubbing operation (25) that is substantially void of light is used to reduce photovoltaic induced corrosion of copper in the drying chamber of the scrubber.
    Type: Grant
    Filed: July 13, 1999
    Date of Patent: August 14, 2001
    Assignee: Motorola, Inc.
    Inventors: Janos Farkas, Brian G. Anthony, Abbas Guvenilir, Mohammed Rabiul Islam, Venkat Kolagunta, John Mendonca, Rajesh Tiwari, Suresh Venkatesan
  • Patent number: 5960270
    Abstract: A method for forming a metal gate MOS transistor begins by forming source and drain electrodes (26, 28, and/or 118) within a substrate (12 or 102). These source and drain regions (26, 28, and 118) are self-aligned to a lithographically-patterned feature (24 or 108). After formation of the source and drain regions, the features (24 and 108 are processed to fill these features with a metallic gate layer (28a or 128a). This metal layer (28a or 128a) is then chemically mechanically polished (CMPed) to form a metallic plug region (28b or 128b) within the features (24 or 108). The plug region (28b or 128b) is formed in either an inlaid or dual inlaid manner wherein this metallic plug region (28b or 128b) is self-aligned to the previously formed source and drain regions and preferably functions as a metal MOS gate region.
    Type: Grant
    Filed: August 11, 1997
    Date of Patent: September 28, 1999
    Assignee: Motorola, Inc.
    Inventors: Veena Misra, Suresh Venkatesan, Christopher C. Hobbs, Brad Smith, Jeffrey S. Cope, Earnest B. Wilson
  • Patent number: 5736435
    Abstract: A process for fabricating a MOSFET on an SOI substrate includes the formation of an active region (14) isolated by field isolation regions (16, 18) and by an insulating layer (12). A recess (26) is formed in the active region (14) using a masking layer (22) having an opening (24) therein. A gate dielectric layer (32) is formed in the recess (26) and a polycrystalline silicon layer (34) is deposited to overlie the masking layer (22), and to fill the recess (26). A planarization process is carried out to form a gate electrode (36) in the recess (26), and source and drain regions (40, 42) are formed in a self-aligned manner to the gate electrode (36). A channel region (44) resides intermediate to the source and drain regions (40, 42) and directly below the gate electrode (36).
    Type: Grant
    Filed: July 3, 1995
    Date of Patent: April 7, 1998
    Assignee: Motorola, Inc.
    Inventors: Suresh Venkatesan, Stephen Poon, Jeffrey Lutze, Sergio Ajuria
  • Patent number: 5627097
    Abstract: A CMOS device having reduced parasitic junction capacitance and a process for fabrication of the device. The device includes an a portion (20') of an undoped epitaxial layer (20) vertically separating source and drain regions (52 and 53, 54 and 55) from buried layers (16, 18) formed in a semiconductor substrate (12). The undoped epitaxial layer (20) reduces the junction capacitance of the source and drain regions by providing an intrinsic silicon region physically separating regions of high dopant concentration from the source and drain regions. Additionally, MOS transistors fabricated in accordance with the invention have fully self-aligned channel regions extending from the upper surface (22) of the undoped epitaxial layer (20) to the buried layers (16, 18) residing in the semiconductor substrate (12).
    Type: Grant
    Filed: July 3, 1995
    Date of Patent: May 6, 1997
    Assignee: Motorola, Inc.
    Inventors: Suresh Venkatesan, Stephen Poon, Jeffrey Lutze