Patents by Inventor Subhas Bothra

Subhas Bothra 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: 6649253
    Abstract: A method of using films having optimized optical properties for chemical mechanical polishing (CMP) endpoint detection. Specifically, one embodiment of the present invention includes a method for improving chemical mechanical polishing endpoint detection. The method comprises the step of depositing a dielectric layer over a reflectance stop layer. The reflectance stop layer is disposed above a component that is disposed on a semiconductor wafer. During a determination of the thickness of the dielectric layer using a reflected signal of light, the reflectance stop layer substantially reduces any light from reflecting off of the component. Therefore, the present invention provides a method and system that provides more accurate endpoint detection during a CMP process of semiconductor wafers. As a result of the present invention, an operator of a CMP machine knows precisely when to stop a CMP process of a semiconductor wafer.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: November 18, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Subhas Bothra, Milind G. Weling
  • Publication number: 20030170989
    Abstract: A semiconductor inductor and a method for making a semiconductor inductor are provided. An oxide layer disposed over a substrate is etched to form an interconnect metallization trench within the oxide layer. The oxide layer is also etched to form a first inductor trench within the oxide layer such that the first inductor trench is defined in an inductor geometry. The oxide layer is then etched to form at least one via in the interconnect metallization trench and a second inductor trench over the first inductor trench in the oxide layer. The second inductor trench also has the inductor geometry. After the oxide layer is etched, the at least one via, the second inductor trench, the interconnect metallization trench and the first inductor trench are filled with copper. The semiconductor inductor is configured to have a low resistance and a high quality factor.
    Type: Application
    Filed: April 2, 2003
    Publication date: September 11, 2003
    Applicant: PHILIPS ELECTRONICS NORTH AMERICA CORP.
    Inventor: Subhas Bothra
  • Patent number: 6573148
    Abstract: A semiconductor inductor and a method for making a semiconductor inductor are provided. An oxide layer disposed over a substrate is etched to form an interconnect metallization trench within the oxide layer. The oxide layer is also etched to form a first inductor trench within the oxide layer such that the first inductor trench is defined in an inductor geometry. The oxide layer is then etched to form at least one via in the interconnect metallization trench and a second inductor trench over the first inductor trench in the oxide layer. The second inductor trench also has the inductor geometry. After the oxide layer is etched, the at least one via, the second inductor trench, the interconnect metallization trench and the first inductor trench are filled with copper. The semiconductor inductor is configured to have a low resistance and a high quality factor.
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: June 3, 2003
    Assignee: Koninklljke Philips Electronics N.V.
    Inventor: Subhas Bothra
  • Patent number: 6569757
    Abstract: A method of forming a co-axial interconnect line in a dielectric layer is provided. The method includes defining a trench in the dielectric layer and then forming a shield metallization layer within the trench. After forming the shield metallization layer, a conformal oxide layer is deposited within the shield metallization layer. A center conductor is then formed within the conformal oxide layer. Once the center conductor is formed, a fill oxide layer is deposited over the center conductor. A cap metallization layer is then formed over the fill oxide layer and is in contact with the shield metallization layer.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: May 27, 2003
    Assignee: Philips Electronics North America Corporation
    Inventors: Milind Weling, Subhas Bothra, Calvin Todd Gabriel, Michael Misheloff
  • Patent number: 6545338
    Abstract: A method for making a semiconductor device with integrated CMOS circuitry and RF circuitry fabricated over a semiconductor wafer, and a semiconductor device with integrated CMOS circuitry and RF circuitry fabricated over a semiconductor wafer is provided. The method includes forming a lower metallization layer and a lower dielectric layer over the lower metallization layer. A metallization line is formed over the lower dielectric layer with an upper dielectric layer over the metallization line. An upper metallization layer is then formed over the upper dielectric layer. After this is completed, oxide spacers are formed along the sides of the lower dielectric layer, the metallization line, and the upper dielectric layer. Finally, an encapsulating metallization layer is formed over the oxide spacers such that the lower metallization layer, the upper metallization layer and the encapsulating metallization layer define an outer shield and the metallization line defines an inner conductor of an RF line.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: April 8, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Subhas Bothra, Calvin Todd Gabriel, Michael Misheloff, Milind Weling
  • Publication number: 20020192919
    Abstract: A high density MIM capacitor structure and method of manufacturing the same is disclosed for integrated circuits having multiple metal layer interconnections. The capacitor structure is formed between selected first and second metallic interconnections which are separated by an insulating intermetallic oxide layer. A first metal-dielectric-metal layer capacitor is created over and with a portion of the first metallic interconnection and a second metal-dielectric-metal layer capacitor is created under and with a portion of the second metallic interconnection. A first metal via through the insulating intermetallic oxide layer connects the first metal-dielectric-metal layer capacitor and the second metal-dielectric-metal layer capacitor to form a first terminal of the capacitor structure and a second metal via through the insulating intermetallic oxide layer connects the first metallic interconnection portion and the second metallic interconnection portion to form a second terminal of the capacitor structure.
    Type: Application
    Filed: April 26, 2001
    Publication date: December 19, 2002
    Inventor: Subhas Bothra
  • Patent number: 6492716
    Abstract: Embodiments of the present invention provide a seal ring which includes a plurality of cuts separating the seal ring into seal ring portions which are disposed adjacent to different circuits in the integrated circuit die. The cuts reduce the noise coupling among the different circuits through the seal ring. To further isolate the sensitive RF/analog circuits from the noise generated by the digital circuit, the seal ring may be electrically (for dc noise) isolated from the substrate. This is accomplished, for instance, by inserting a polysilicon layer and gate oxide between the seal ring and the substrate. In addition, an n-well/p-well capacitor may be formed in series with the gate oxide, for instance, by implanting an n-well below the polysilicon layer in a p-type substrate.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: December 10, 2002
    Assignee: ZeeVo, Inc.
    Inventors: Subhas Bothra, Thomas G. McKay, Ravi Jhota
  • Patent number: 6472253
    Abstract: A programmable device and methods for making the programmable device are provided. The programmable device includes a link metallization line with an oxide layer defined above the link metallization line. A via hole is patterned in the oxide layer which defines a path to the link metallization line. A programming metallization line is defined over the oxide layer. The programming metallization line has an overlap portion that lies over the via hole. The overlap portion is configured to melt into the via hole to define a programming link between the link metallization line and the programming metallization line. In one example, the melting is accomplished by implementing a laser that can direct laser energy toward a desired programmable device to achieve the desired programming.
    Type: Grant
    Filed: November 15, 1999
    Date of Patent: October 29, 2002
    Assignee: VLSI Technology, Inc.
    Inventor: Subhas Bothra
  • Patent number: 6411367
    Abstract: A system and method is disclosed for enhancing an optical lithography process by capturing light diffracted from a mask having features to be exposed onto a wafer. In one embodiment, a system of the present invention has in place a mask, a wafer and a reduction lens such that the reduction lens is placed between the mask and the wafer in order to direct and expose the mask's features onto the wafer. Furthermore, a reflective member is disposed proximate to the reduction lens. In order to achieve finer resolution of the mask image on the wafer, this reflective member captures diffracted light diffracting beyond the reduction lens and redirects the diffracted light to pass through the reduction lens such that the diffracted light is redirected onto the wafer. In so doing, the reflective member resolves the mask image on the wafer in more detail than is possible by an optical lithography process using no such reflective member.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: June 25, 2002
    Assignee: VLSI Technology, Inc.
    Inventors: Daniel C. Baker, Subhas Bothra, Satyendra Sethi
  • Patent number: 6399432
    Abstract: For use with sub-micron CMOS technologies, a gate etch process improves control of the etch profile. Gate stacks utilize N-type or P-type doped amorphous or poly silicon to enhance device performance. However, the different etching characteristics of the N-type versus the P-type amorphous or poly silicon material can result in a localized breakthrough of the underlying thin gate oxide adjacent to the edge of the gate stack, especially in the N doped active regions. According to one example embodiment, this localized breakthrough (“microtrenching”) is avoided by building the gate stacks with undoped amorphous or poly silicon to the desired configuration, masking the gate stacks with a dielectric layer, planarizing the dielectric layer and then implanting the N-type or P-type species into the selected gate stack.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: June 4, 2002
    Assignee: Philips Semiconductors Inc.
    Inventors: Tammy Zheng, Subhas Bothra
  • Patent number: 6387720
    Abstract: A waveguide structure and method of making a waveguide for communicating optical signals is provided. The waveguide structure is made using standard CMOS fabrication operations and is integrated on the same chip having digital CMOS circuitry. An example method of making the waveguide includes forming a contact through a dielectric layer down to a substrate and coating sidewalls of the contact with a first metallization coating. The contact is then filled with a dielectric material. A partial waveguide structure is formed over the first metallization coating and the dielectric material of the contact. The partial waveguide structure is defined by a waveguide dielectric structure and a second metallization coating that is defined over the waveguide dielectric structure. A third metallization coating is then formed to define spacers along sides of the partial waveguide structure, the first metallization coating, the second metallization coating.
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: May 14, 2002
    Assignee: Phillips Electronics North America Corporation
    Inventors: Michael Misheloff, Subhas Bothra, Calvin Todd Gabriel, Milind Weling
  • Patent number: 6387797
    Abstract: A method of manufacturing semiconductors is provided which avoids metal deposition in voids formed in the dielectric between interconnects. In a preferred embodiment, an etch stop recess portion is provided over the dielectric which encloses the interconnects to prevent via openings from extending into the voids during the etching of the via openings. Accordingly, metal deposition of the voids during metal deposition of the vias is avoided. As a result, the semiconductors so formed has reduced capacitance between the interconnects and improved reliability since the voids are cleared of any metal deposition.
    Type: Grant
    Filed: January 20, 1999
    Date of Patent: May 14, 2002
    Assignee: Philips Electronics No. America Corp.
    Inventors: Subhas Bothra, Rao Annapragada
  • Patent number: 6372522
    Abstract: A system for repairable interconnect links using laser energy in a semiconductor integrated circuit die. The integrated circuit die is fabricated to include a plurality of interconnect links. At least a first and a second interconnect element are included in the integrated circuit die. The first and second interconnect elements are couple via an interconnect link. An anti-reflective layer is disposed on a surface above the interconnect link. The anti-reflective layer is configured to increase an amount of laser energy absorbed by the interconnect link in order to fuse the interconnect link, and thereby repair the integrated circuit die.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: April 16, 2002
    Assignee: VLSI Technology, Inc.
    Inventors: Milind Ganesh Weling, Subhas Bothra, Satyendra Sethi
  • Patent number: 6355969
    Abstract: A method for making, and a programmable structure for use in a semiconductor chip is provided. The method includes forming a lower metallization layer, and forming an upper metallization layer. The upper metallization layer has a first portion and a second portion. An eroded via is formed between the lower metallization layer and the first portion of the upper metallization layer, and a conductive via is formed between the lower metallization layer and the second portion of the upper metallization layer. The method then includes applying a current between the lower metallization layer and the second portion of the upper metallization layer. The current is configured to cause electromigration in the lower metallization layer such that some of the electromigration fills the eroded via between the lower metallization layer and first portion of the upper metallization layer. The current, if programming is desired, is applied from pads of the semiconductor chip either directly or by way of a programming circuit.
    Type: Grant
    Filed: September 27, 1999
    Date of Patent: March 12, 2002
    Assignee: Philips Electronics North America Corporation
    Inventors: Stephen L. Skala, Subhas Bothra
  • Patent number: 6327695
    Abstract: Disclosed is a network of on-chip capacitive structures for suppressing power supply inductive noise, methods for making, and systems for designing the on-chip capacitive structures. The network includes a plurality of dummy active regions that are dispersed throughout an integrated circuit design that has a plurality of active regions. The plurality of dummy active regions are separated from the plurality of active regions by at least a bloat distance. The network further includes a network of dummy polysilicon lines that are configured to overlie selected dummy active regions. The network of dummy polysilicon lines that overlie the selected dummy active regions function as dummy gates. In this embodiment, the selected dummy active regions and the dummy polysilicon lines that overlie the selected dummy active regions form the network of on-chip capacitive structures.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: December 4, 2001
    Assignee: Philips Electronics North America Corporation
    Inventors: Subhas Bothra, Paul R. Findley
  • Patent number: 6323113
    Abstract: The present invention provides methods for intelligently filling a gate layer with dummy fill patterns to produce a target pattern density. A gate layout defining gate areas on the gate layer is provided along with a diffusion layout defining active diffusion areas over a semiconductor substrate. For the gate layout, a pattern density is determined. Then, the areas not occupied by the gate areas and the diffusion areas are determined. Additionally, a range of pattern densities is provided in a set of predefined fill patterns with each predefined fill pattern having a plurality of dummy fill patterns and being associated with a pattern density within the provided range of pattern densities. Among the set of predefined fill patterns, a predefined fill pattern is selected for producing the target pattern density. Then, the gate layer is filled by placing the dummy fill patterns of the selected predefined fill pattern in the areas not occupied by the gate areas and the diffusion areas.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: November 27, 2001
    Assignee: Philips Electronics North America Corporation
    Inventors: Calvin T. Gabriel, Tammy D. Zheng, Subhas Bothra, Harlan L. Sur, Jr.
  • Patent number: 6313466
    Abstract: In a method for determining the nitrogen concentration in a film of nitrided oxide material formed over a semiconductor wafer during fabrication of a semiconductor device an optical property of the film of nitrided oxide material is determined. The determined optical property is used to determine the nitrogen concentration in the film of nitrided oxide material. In one embodiment the optical property, e.g., extinction coefficient, k, is correlated to the nitrogen concentration measured by secondary ion mass spectroscopy. In a method of making a semiconductor device a film of nitrided oxide material is formed over a plurality of semiconductor wafers in a fab. The nitrogen concentration in the film of nitrided oxide material is monitored by periodically subjecting one of the wafers to an in-line test in the fab.
    Type: Grant
    Filed: May 12, 1999
    Date of Patent: November 6, 2001
    Assignee: Philips Electronics North America Corp.
    Inventors: Christopher S. Olsen, Subhas Bothra
  • Patent number: 6303192
    Abstract: A method for making a multi-layered integrated circuit structure, includes depositing a methyl compound spin on glass layer over a substrate. The spin on glass layer is treated by plasma-deposition to form a SiO2 skin on the methyl compound spin on glass layer and then treated again by plasma-deposition to form a cap layer which adheres to the SiO2 skin.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: October 16, 2001
    Assignee: Philips Semiconductor Inc.
    Inventors: Rao V. Annapragada, Tekle M. Tafari, Subhas Bothra
  • Publication number: 20010026018
    Abstract: Metal bond pads are formed over active circuitry in a semiconductor chip in a reliable and cost effective manner. According to an example embodiment of the present invention, a metal bond pad is formed over circuitry in the semiconductor chip. A metal layer is formed over the circuitry and the metal bond pad, and a diffusion barrier layer is formed between the metal layer and the metal bond pad. In this manner, additional metal can be formed on the pad site using only one additional mask step, and thicker metal at the pad site improves the reliability of the chip by providing for a metal cushion at the pad useful in subsequent wire bonding processes.
    Type: Application
    Filed: June 5, 2001
    Publication date: October 4, 2001
    Applicant: Philips Semiconductors, Inc.
    Inventors: Stephen L. Skala, Subhas Bothra, Emmanuel Demuizon
  • Patent number: 6297557
    Abstract: Disclosed is an aluminum filled via hole for use in a semiconductor interconnect structure. The aluminum filled via hole of the semiconductor interconnect structure includes a first patterned metallization layer lying over a first dielectric layer. A second dielectric layer overlying the first patterned metallization layer and the first dielectric layer. An aluminum filled via hole defined through the second dielectric layer and in contact with the first patterned metallization layer. The aluminum filled via hole has an electromigration barrier cap over a topmost portion of the aluminum filled via hole that is substantially level with the second dielectric layer. The electromigration barrier cap having a thickness of between about 500 angstroms and about 2,500 angstroms.
    Type: Grant
    Filed: August 13, 1998
    Date of Patent: October 2, 2001
    Assignee: Philips Electronics North America Corp.
    Inventor: Subhas Bothra