Patents by Inventor Akram A. Salman

Akram A. Salman 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: 9754930
    Abstract: An integrated circuit includes an NMOS SCR in which a p-type body well of the NMOS transistor provides a base layer for a vertical NPN layer stack. The base layer is formed by implanting p-type dopants using an implant mask which has a cutout mask element over the base area, so as to block the p-type dopants from the base area. The base layer is implanted concurrently with p-type body wells under NMOS transistors in logic components in the integrated circuit. Subsequent anneals cause the p-type dopants to diffuse into the base area, forming a base with a lower doping density that adjacent regions of the body well of the NMOS transistor in the NMOS SCR. The NMOS SCR may have a symmetric transistor, a drain extended transistor, or may be a bidirectional NMOS SCR with a symmetric transistor integrated with a drain extended transistor.
    Type: Grant
    Filed: October 13, 2016
    Date of Patent: September 5, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Henry Litzmann Edwards, Akram A. Salman
  • Publication number: 20170250174
    Abstract: An apparatus includes: a first SCR device having a first source terminal coupled to a signal terminal, a first body terminal coupled to the first source terminal, a first gate terminal coupled to the signal terminal, and a first drain terminal; a second SCR device having a second drain terminal coupled to the first drain terminal, a second gate terminal coupled to a reference voltage terminal; and a second source terminal coupled to the reference voltage terminal. The apparatus also includes: a third SCR device having a third source terminal coupled to the signal terminal, a third gate terminal coupled to the first gate terminal, and a third drain terminal; a first capacitor coupled between the third drain terminal and the second gate terminal; and a second capacitor coupled between the second gate terminal and the reference voltage terminal.
    Type: Application
    Filed: September 2, 2016
    Publication date: August 31, 2017
    Inventors: Yang Xiu, Akram A. Salman, Farzan Farbiz
  • Patent number: 9711643
    Abstract: A semiconductor device includes a body and a transistor fabricated into the body. Isolation material at least partially encases the body. Biasing is coupled to the isolation material, wherein the biasing is for changing the electric potential of the isolation material in response to an electrostatic discharge event.
    Type: Grant
    Filed: November 24, 2014
    Date of Patent: July 18, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Aravind C. Appaswamy, Akram A. Salman, Farzan Farbiz, Gianluca Boselli
  • Patent number: 9633991
    Abstract: An integrated circuit includes a bidirectional ESD device which has a plurality of parallel switch legs. Each switch leg includes a first current switch and a second current switch in a back-to-back configuration. A first current supply node of each first current switch is coupled to a first terminal of the ESD device. A second current supply node of each second current switch is coupled to a second terminal of the ESD device. A first current collection node of each first current switch is coupled to a second current collection node of the corresponding second current switch. The first current collection nodes in each first current switch is not coupled to any other first current collection node, and similarly, the second current collection node in each instance second current switch is not coupled to any other second current collection node.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: April 25, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Akram A. Salman, Farzan Farbiz, Ann Margaret Concannon, Gianluca Boselli
  • Patent number: 9633990
    Abstract: An integrated circuit and method with a bidirectional ESD transistor. A base diffusion separates an emitter diffusion and a collector diffusion. Silicide is blocked from the base diffusion, the emitter-base junction, the collector-base junction, and from equal portions of the emitter diffusion and the collector diffusions.
    Type: Grant
    Filed: June 21, 2016
    Date of Patent: April 25, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Akram A. Salman, Farzan Farbiz, Aravind C. Appaswamy, Ann Margaret Concannon
  • Publication number: 20170098643
    Abstract: According to an embodiment, a bipolar transistor is disclosed for Electrostatic discharge (ESD) management in integrated circuits. The bipolar transistor enables vertical current flow in a bipolar transistor cell configured for ESD protection. The bipolar transistor includes a selectively embedded P-type floating buried layer (PBL). The floating P-region is added in a standard NPN cell. During an ESD event, the base of the bipolar transistor extends to the floating P-region with a very small amount of current. The PBL layer can provide more holes to support the current resulting in decreased holding voltage of the bipolar transistor. With the selective addition of floating P-region, the current scalability of the bipolar transistor at longer pulse widths can be significantly improved.
    Type: Application
    Filed: June 3, 2016
    Publication date: April 6, 2017
    Applicant: Texas Instruments Incorporated
    Inventors: YANG XIU, ARAVIND C. APPASWAMY, AKRAM SALMAN, MARIANO DISSEGNA
  • Publication number: 20170033096
    Abstract: An integrated circuit includes an NMOS SCR in which a p-type body well of the NMOS transistor provides a base layer for a vertical NPN layer stack. The base layer is formed by implanting p-type dopants using an implant mask which has a cutout mask element over the base area, so as to block the p-type dopants from the base area. The base layer is implanted concurrently with p-type body wells under NMOS transistors in logic components in the integrated circuit. Subsequent anneals cause the p-type dopants to diffuse into the base area, forming a base with a lower doping density that adjacent regions of the body well of the NMOS transistor in the NMOS SCR. The NMOS SCR may have a symmetric transistor, a drain extended transistor, or may be a bidirectional NMOS SCR with a symmetric transistor integrated with a drain extended transistor.
    Type: Application
    Filed: October 13, 2016
    Publication date: February 2, 2017
    Inventors: Henry Litzmann EDWARDS, Akram A. SALMAN
  • Patent number: 9496252
    Abstract: An integrated circuit includes an NMOS SCR in which a p-type body well of the NMOS transistor provides a base layer for a vertical NPN layer stack. The base layer is formed by implanting p-type dopants using an implant mask which has a cutout mask element over the base area, so as to block the p-type dopants from the base area. The base layer is implanted concurrently with p-type body wells under NMOS transistors in logic components in the integrated circuit. Subsequent anneals cause the p-type dopants to diffuse into the base area, forming a base with a lower doping density that adjacent regions of the body well of the NMOS transistor in the NMOS SCR. The NMOS SCR may have a symmetric transistor, a drain extended transistor, or may be a bidirectional NMOS SCR with a symmetric transistor integrated with a drain extended transistor.
    Type: Grant
    Filed: February 12, 2016
    Date of Patent: November 15, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Henry Litzmann Edwards, Akram A. Salman
  • Publication number: 20160300831
    Abstract: An integrated circuit and method with a bidirectional ESD transistor. A base diffusion separates an emitter diffusion and a collector diffusion. Silicide is blocked from the base diffusion, the emitter-base junction, the collector-base junction, and from equal portions of the emitter diffusion and the collector diffusions.
    Type: Application
    Filed: June 21, 2016
    Publication date: October 13, 2016
    Inventors: Akram A. Salman, Farzan Farbiz, Aravind C. Appaswamy, Ann Margaret Concannon
  • Patent number: 9431384
    Abstract: An electrostatic discharge (ESD) protection circuit (FIG. 5A) for an integrated circuit is disclosed. The integrated circuit includes a first ESD cell having a current path coupled between a first terminal and a second terminal. A second ESD cell has a current path coupled between the second terminal and a power supply terminal. A passive circuit is connected in parallel with one of the first and second ESD cells.
    Type: Grant
    Filed: March 21, 2014
    Date of Patent: August 30, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Farzan Farbiz, John Eric Kunz, Jr., Aravind C. Appaswamy, Akram A. Salman
  • Patent number: 9418197
    Abstract: A method of designing a diode includes generating a layout of the diode and calculating a calculated voltage overshoot based on the layout. The calculating includes calculating variables of: the length of an N region of the diode; current density during an ESD event; electron charge; hole mobility; electron mobility; doping concentration of the diode; and rise time of the ESD event.
    Type: Grant
    Filed: February 2, 2015
    Date of Patent: August 16, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Farzan Farbiz, Aravind C. Appaswamy, Akram A. Salman, Gianluca Boselli
  • Publication number: 20160224716
    Abstract: A method of designing a diode includes generating a layout of the diode and calculating a calculated voltage overshoot based on the layout. The calculating includes calculating variables of: the length of an N region of the diode; current density during an ESD event; electron charge; hole mobility; electron mobility; doping concentration of the diode; and rise time of the ESD event.
    Type: Application
    Filed: February 2, 2015
    Publication date: August 4, 2016
    Inventors: Farzan Farbiz, Aravind C. Appaswamy, Akram A. Salman, Gianluca Boselli
  • Patent number: 9397085
    Abstract: An integrated circuit and method with a bidirectional ESD transistor. A base diffusion separates an emitter diffusion and a collector diffusion. Silicide is blocked from the base diffusion, the emitter-base junction, the collector-base junction, and from equal portions of the emitter diffusion and the collector diffusions.
    Type: Grant
    Filed: December 22, 2014
    Date of Patent: July 19, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Akram A. Salman, Farzan Farbiz, Aravind C. Appaswamy, Ann Margaret Concannon
  • Publication number: 20160163691
    Abstract: An integrated circuit includes an NMOS SCR in which a p-type body well of the NMOS transistor provides a base layer for a vertical NPN layer stack. The base layer is formed by implanting p-type dopants using an implant mask which has a cutout mask element over the base area, so as to block the p-type dopants from the base area. The base layer is implanted concurrently with p-type body wells under NMOS transistors in logic components in the integrated circuit. Subsequent anneals cause the p-type dopants to diffuse into the base area, forming a base with a lower doping density that adjacent regions of the body well of the NMOS transistor in the NMOS SCR. The NMOS SCR may have a symmetric transistor, a drain extended transistor, or may be a bidirectional NMOS SCR with a symmetric transistor integrated with a drain extended transistor.
    Type: Application
    Filed: February 12, 2016
    Publication date: June 9, 2016
    Inventors: Henry Litzmann EDWARDS, Akram A. SALMAN
  • Publication number: 20160156176
    Abstract: An electrostatic discharge (ESD) protection circuit includes a substrate having a semiconductor surface that the ESD protection circuit formed thereon. A first ESD cell is stacked in series with at least a second ESD cell. An active shunt transistor is electrically in parallel with the first ESD cell or second ESD cell, where the active shunt includes a control node. A trigger circuit has a trigger input and a trigger output, wherein the trigger output is coupled to the control node.
    Type: Application
    Filed: December 2, 2014
    Publication date: June 2, 2016
    Inventors: JOHN ERIC KUNZ, JR., FARZAN FARBIZ, ARAVIND C. APPASWAMY, AKRAM A. SALMAN
  • Publication number: 20160086936
    Abstract: An integrated circuit includes a bidirectional ESD device which has a plurality of parallel switch legs. Each switch leg includes a first current switch and a second current switch in a back-to-back configuration. A first current supply node of each first current switch is coupled to a first terminal of the ESD device. A second current supply node of each second current switch is coupled to a second terminal of the ESD device. A first current collection node of each first current switch is coupled to a second current collection node of the corresponding second current switch. The first current collection nodes in each first current switch is not coupled to any other first current collection node, and similarly, the second current collection node in each instance second current switch is not coupled to any other second current collection node.
    Type: Application
    Filed: November 23, 2015
    Publication date: March 24, 2016
    Inventors: Akram A. Salman, Farzan Farbiz, Ann Margaret Concannon, Gianluca Boselli
  • Patent number: 9293460
    Abstract: An integrated circuit includes an NMOS SCR in which a p-type body well of the NMOS transistor provides a base layer for a vertical NPN layer stack. The base layer is formed by implanting p-type dopants using an implant mask which has a cutout mask element over the base area, so as to block the p-type dopants from the base area. The base layer is implanted concurrently with p-type body wells under NMOS transistors in logic components in the integrated circuit. Subsequent anneals cause the p-type dopants to diffuse into the base area, forming a base with a lower doping density that adjacent regions of the body well of the NMOS transistor in the NMOS SCR. The NMOS SCR may have a symmetric transistor, a drain extended transistor, or may be a bidirectional NMOS SCR with a symmetric transistor integrated with a drain extended transistor.
    Type: Grant
    Filed: August 24, 2012
    Date of Patent: March 22, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Henry Litzmann Edwards, Akram A. Salman
  • Publication number: 20160079228
    Abstract: An electrostatic discharge (ESD) protection circuit (FIG. 3C) is disclosed. The circuit includes a bipolar transistor (304) having a base, collector, and emitter. Each of a plurality of diodes (308-316) has a first terminal coupled to the base and a second terminal coupled to the collector. The collector is connected to a first terminal (V+). The emitter is connected to a first power supply terminal (V?).
    Type: Application
    Filed: November 25, 2015
    Publication date: March 17, 2016
    Inventors: Henry L. Edwards, Akram A. Salman, Lili Yu
  • Publication number: 20160079750
    Abstract: An electrostatic discharge (ESD) protection circuit (FIG. 3C) is disclosed. The circuit includes a bipolar transistor (304) having a base, collector, and emitter. Each of a plurality of diodes (308-316) has a first terminal coupled to the base and a second terminal coupled to the collector. The collector is connected to a first terminal (V+). The emitter is connected to a first power supply terminal (V?).
    Type: Application
    Filed: November 25, 2015
    Publication date: March 17, 2016
    Inventors: Henry L. Edwards, Akram A. Salman, Lili Yu
  • Publication number: 20160079227
    Abstract: An electrostatic discharge (ESD) protection circuit (FIG. 3C) is disclosed. The circuit includes a bipolar transistor (304) having a base, collector, and emitter. Each of a plurality of diodes (308-316) has a first terminal coupled to the base and a second terminal coupled to the collector. The collector is connected to a first terminal (V+). The emitter is connected to a first power supply terminal (V?).
    Type: Application
    Filed: November 25, 2015
    Publication date: March 17, 2016
    Inventors: Henry L. Edwards, Akram A. Salman, Lili Yu