Patents by Inventor Manoj Mehrotra

Manoj Mehrotra 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: 20150008532
    Abstract: A transistor is formed in a semiconductor substrate with a gate over a channel region, source/drain extension regions in the substrate adjacent the channel region, and source/drain regions in the substrate adjacent the source/drain extension regions. Silicide is formed on the source/drain extension regions and the source/drain regions so that the silicide has a first thickness over the source/drain extension regions and a second thickness over source/drain regions, with the second thickness being greater than the first thickness. Silicide on the source/drain extension regions lowers transistor series resistance which boosts transistor performance and also protects the source/drain extension regions from silicon loss and silicon damage during contact etch.
    Type: Application
    Filed: September 26, 2014
    Publication date: January 8, 2015
    Inventor: Manoj Mehrotra
  • Patent number: 8906770
    Abstract: Gate cross diffusion in a semiconductor structure is substantially reduced or eliminated by forming multiple n-type gate regions with different dopant concentrations and multiple p-type gate regions with different dopant concentrations so that the n-type gate region with the lowest dopant concentration touches the p-type gate region with the lowest dopant concentration.
    Type: Grant
    Filed: October 22, 2013
    Date of Patent: December 9, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Manoj Mehrotra
  • Patent number: 8877595
    Abstract: A transistor is formed in a semiconductor substrate with a gate over a channel region, source/drain extension regions in the substrate adjacent the channel region, and source/drain regions in the substrate adjacent the source/drain extension regions. Silicide is formed on the source/drain extension regions and the source/drain regions so that the silicide has a first thickness over the source/drain extension regions and a second thickness over source/drain regions, with the second thickness being greater than the first thickness. Silicide on the source/drain extension regions lowers transistor series resistance which boosts transistor performance and also protects the source/drain extension regions from silicon loss and silicon damage during contact etch.
    Type: Grant
    Filed: November 2, 2011
    Date of Patent: November 4, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Manoj Mehrotra
  • Publication number: 20140175597
    Abstract: An isolation trench in a substrate of a semiconductor device includes a first shallow portion, a transition region, and a second deeper portion. The isolation trench contains a dielectric filler. The isolation trench is formed by first forming a first shallow portion of the isolation trench, forming polysilicon sidewalls on the first shallow portion, and then etching the second deeper portion.
    Type: Application
    Filed: February 26, 2014
    Publication date: June 26, 2014
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Manoj Mehrotra
  • Publication number: 20140124874
    Abstract: The gate-to-source and gate-to-drain overlap capacitance of a MOS transistor with a metal gate and a high-k gate dielectric are reduced by forming the high-k gate dielectric along the inside of a sidewall structure which has been formed to lie further away from the source and the drain.
    Type: Application
    Filed: November 8, 2012
    Publication date: May 8, 2014
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Manoj Mehrotra, Hiroaki Niimi
  • Patent number: 8691661
    Abstract: An isolation trench in a substrate of a semiconductor device includes a first shallow portion, a transition region, and a second deeper portion. The isolation trench contains a dielectric filler. The isolation trench is formed by first forming a first shallow portion of the isolation trench, forming polysilicon sidewalls on the first shallow portion, and then etching the second deeper portion.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: April 8, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Manoj Mehrotra
  • Patent number: 8685831
    Abstract: An isolation trench in a substrate of a semiconductor device includes a first shallow portion with a dielectric sidewall and a second deeper portion without a dielectric sidewall. The isolation trench is formed by forming a first shallow portion of the trench, forming dielectric sidewalls on the first shallow portion, and then etching the substrate below the first shallow portion to form the second deeper portion. Shallow isolation trenches may be formed simultaneously with the etching of the second deeper portion.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: April 1, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Manoj Mehrotra
  • Publication number: 20140087536
    Abstract: Gate cross diffusion in a semiconductor structure is substantially reduced or eliminated by forming multiple n-type gate regions with different dopant concentrations and multiple p-type gate regions with different dopant concentrations so that the n-type gate region with the lowest dopant concentration touches the p-type gate region with the lowest dopant concentration.
    Type: Application
    Filed: October 22, 2013
    Publication date: March 27, 2014
    Applicant: Texas Instruments Incorporated
    Inventor: Manoj MEHROTRA
  • Patent number: 8617954
    Abstract: Provided is a method for manufacturing a gate dielectric. This method, without limitation, includes subjecting a silicon substrate to a first plasma nitridation process to incorporate a nitrogen region therein. This method further includes growing a dielectric material layer over the nitrogen region using a nitrogen containing oxidizer gas, and subjecting the dielectric material layer to a second plasma nitridation process, thereby forming a nitrided dielectric material layer over the nitrogen region.
    Type: Grant
    Filed: October 9, 2007
    Date of Patent: December 31, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Hiroaki Niimi, Manoj Mehrotra
  • Patent number: 8592902
    Abstract: Gate cross diffusion in a semiconductor structure is substantially reduced or eliminated by forming multiple n-type gate regions with different dopant concentrations and multiple p-type gate regions with different dopant concentrations so that the n-type gate region with the lowest dopant concentration touches the p-type gate region with the lowest dopant concentration.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: November 26, 2013
    Assignee: Texas Instrument Incorporated
    Inventor: Manoj Mehrotra
  • Patent number: 8435848
    Abstract: A process of forming a CMOS integrated circuit including integrating SiGe source/drains in the PMOS transistor after source/drain and LDD implants and anneals. A dual layer hard mask is formed on a polysilicon gate layer. The bottom layer prevents SiGe growth on the polysilicon gate. The top layer protects the bottom layer during source/drain spacer removal. A stress memorization layer may be formed on the integrated circuit prior to a source/drain anneal and removed prior to forming a SiGe blocking layer over the NMOS. SiGe spacers may be formed on the PMOS gate to laterally offset the SiGe recesses.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: May 7, 2013
    Assignee: Texas Instruments Incorporated
    Inventor: Manoj Mehrotra
  • Publication number: 20120104540
    Abstract: An isolation trench in a substrate of a semiconductor device includes a first shallow portion, a transition region, and a second deeper portion. The isolation trench contains a dielectric filler. The isolation trench is formed by first forming a first shallow portion of the isolation trench, forming polysilicon sidewalls on the first shallow portion, and then etching the second deeper portion.
    Type: Application
    Filed: October 28, 2011
    Publication date: May 3, 2012
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Manoj Mehrotra
  • Publication number: 20120104503
    Abstract: A transistor is formed in a semiconductor substrate with a gate over a channel region, source/drain extension regions in the substrate adjacent the channel region, and source/drain regions in the substrate adjacent the source/drain extension regions. Silicide is formed on the source/drain extension regions and the source/drain regions so that the silicide has a first thickness over the source/drain extension regions and a second thickness over source/drain regions, with the second thickness being greater than the first thickness. Silicide on the source/drain extension regions lowers transistor series resistance which boosts transistor performance and also protects the source/drain extension regions from silicon loss and silicon damage during contact etch.
    Type: Application
    Filed: November 2, 2011
    Publication date: May 3, 2012
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Manoj Mehrotra
  • Publication number: 20120108021
    Abstract: A process of forming a CMOS integrated circuit including integrating SiGe source/drains in the PMOS transistor after source/drain and LDD implants and anneals. A dual layer hard mask is formed on a polysilicon gate layer. The bottom layer prevents SiGe growth on the polysilicon gate. The top layer protects the bottom layer during source/drain spacer removal. A stress memorization layer may be formed on the integrated circuit prior to a source/drain anneal and removed prior to forming a SiGe blocking layer over the NMOS. SiGe spacers may be formed on the PMOS gate to laterally offset the SiGe recesses.
    Type: Application
    Filed: October 28, 2011
    Publication date: May 3, 2012
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Manoj Mehrotra
  • Publication number: 20120104539
    Abstract: An isolation trench in a substrate of a semiconductor device includes a first shallow portion with a dielectric sidewall and a second deeper portion without a dielectric sidewall. The isolation trench is formed by forming a first shallow portion of the trench, forming dielectric sidewalls on the first shallow portion, and then etching the substrate below the first shallow portion to form the second deeper portion. Shallow isolation trenches may be formed simultaneously with the etching of the second deeper portion.
    Type: Application
    Filed: October 28, 2011
    Publication date: May 3, 2012
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Manoj Mehrotra
  • Patent number: 7960238
    Abstract: An integrated circuit (IC) includes at least one NMOS transistor, wherein the NMOS transistor includes a substrate having a semiconductor surface, and a gate stack formed in or on the surface including a gate electrode on a gate dielectric, wherein a channel region is located in the semiconductor surface below the gate dielectric. A source and a drain region are on opposing sides of the gate stack. An In region having a retrograde profile is under at least a portion of the channel region. The retrograde profile includes (i) a surface In concentration at a semiconductor surface interface with the gate dielectric of less than 5×1016 cm?3, (ii) a peak In concentration at least 20 nm from the semiconductor surface below the gate dielectric, and wherein (iii) the peak In concentration is at least two (2) orders of magnitude higher than the In concentration at the semiconductor surface interface.
    Type: Grant
    Filed: December 29, 2008
    Date of Patent: June 14, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Puneet Kohli, Manoj Mehrotra
  • Patent number: 7897496
    Abstract: Semiconductor doping techniques, along with related methods and structures, are disclosed that produce components having a more tightly controlled source and drain extension region dopant profiles without significantly inducing gate edge diode leakage. The technique follows the discovery that carbon, which may be used as a diffusion suppressant for dopants such as boron, may produce a gate edge diode leakage if present in significant quantities in the source and drain extension regions. As an alternative to placing carbon in the source and drain extension regions, carbon may be placed in the source and drain regions, and the thermal anneal used to activate the dopant may be relied upon to diffuse a small concentration of the carbon into the source and drain extension regions, thereby suppressing dopant diffusion in these regions without significantly inducing gate edge diode leakage.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: March 1, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Puneet Kohli, Nandakumar Mahalingam, Manoj Mehrotra, Song Zhao
  • Patent number: 7846783
    Abstract: A process of fabricating an IC is disclosed in which a polysilicon resistor and a gate region of an MOS transistor are implanted concurrently. The concurrent implantation may be used to reduce steps in the fabrication sequence of the IC. The concurrent implantation may also be used to provide another species of transistor in the IC with enhanced performance. Narrow PMOS transistor gates may be implanted concurrently with p-type polysilicon resistors to increase on-state drive current. PMOS transistor gates over thick gate dielectrics may be implanted concurrently with p-type polysilicon resistors to reduce gate depletion. NMOS transistor gates may be implanted concurrently with n-type polysilicon resistors to reduce gate depletion, and may be implanted concurrently with p-type polysilicon resistors to provide high threshold NMOS transistors in the IC.
    Type: Grant
    Filed: November 5, 2008
    Date of Patent: December 7, 2010
    Assignee: Texas Instruments Incorporated
    Inventors: Manoj Mehrotra, Puneet Kohli
  • Publication number: 20100164003
    Abstract: An integrated circuit (IC) includes at least one NMOS transistor, wherein the NMOS transistor includes a substrate having a semiconductor surface, and a gate stack formed in or on the surface including a gate electrode on a gate dielectric, wherein a channel region is located in the semiconductor surface below the gate dielectric. A source and a drain region are on opposing sides of the gate stack. An In region having a retrograde profile is under at least a portion of the channel region. The retrograde profile includes (i) a surface In concentration at a semiconductor surface interface with the gate dielectric of less than 5×1016 cm?3, (ii) a peak In concentration at least 20 nm from the semiconductor surface below the gate dielectric, and wherein (iii) the peak In concentration is at least two (2) orders of magnitude higher than the In concentration at the semiconductor surface interface.
    Type: Application
    Filed: December 29, 2008
    Publication date: July 1, 2010
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: PUNEET KOHLI, MANOJ MEHROTRA
  • Patent number: 7736983
    Abstract: Pipe defects in n-type lightly doped drain (NLDD) regions and n-type source/drain (NDS) regions are associated with arsenic implants, while excess diffusion in NLDD and NSD regions is mainly due to phosphorus interstitial movement. Carbon implantation is commonly used to reduce phosphorus diffusion in the NLDD, but contributes to gated diode leakage (GDL). In high threshold NMOS transistors GDL is commonly a dominant off-state leakage mechanism. This invention provides a method of forming an NMOS transistor in which no carbon is implanted into the NLDD, and the NSD is formed by a pre-amorphizing implant (PAI), a phosphorus implant and a carbon species implant. Use of carbon in the NDS allows a higher concentration of phosphorus, resulting in reduced series resistance and reduced pipe defects. An NMOS transistor with less than 1·1014 cm?2 arsenic in the NSD and a high threshold NMOS transistor formed with the inventive method are also disclosed.
    Type: Grant
    Filed: January 10, 2008
    Date of Patent: June 15, 2010
    Assignee: Texas Instruments Incorporated
    Inventors: Puneet Kohli, Manoj Mehrotra, Shaoping Tang