Patents by Inventor Thomas E. Harrington, III

Thomas E. Harrington, III 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: 9117709
    Abstract: Improvement of key electrical specifications of vertical semiconductor devices, usually found in the class of devices known as discrete semiconductors, has a direct impact on the performance achievement and power efficiency of the systems in which these devices are used. Imprecise vertical device specifications cause system builders to either screen incoming devices for their required specification targets or to design their system with lower performance or lower efficiency than desired. Disclosed is an architecture and method for achieving a desired target specification for a vertical semiconductor device. Precise trimming of threshold voltage improves targeting of both on-resistance and switching time. Precise trimming of gate resistance also improves targeting of switching time. Precise trimming of a device's effective width improves targeting of both on-resistance and current-carrying capability.
    Type: Grant
    Filed: November 26, 2013
    Date of Patent: August 25, 2015
    Assignee: D3 Semiconductor LLC
    Inventor: Thomas E. Harrington, III
  • Patent number: 9117899
    Abstract: A semiconductor field-effect device is disclosed that utilizes an octagonal or inverse-octagonal deep trench super-junction in combination with an octagonal or inverse-octagonal gate trench. The field-effect device achieves improved packing density, improved current density, and improved on resistance, while at the same time maintaining compatibility with the multiple-of-45°-angles of native photomask processing and having well characterized (010), (100) and (110) (and their equivalent) silicon sidewall surfaces for selective epitaxial refill and gate oxidation, resulting in improved scalability. By varying the relative length of each sidewall surface, devices with differing threshold voltages can be achieved without additional processing steps. Mixing trenches with varying sidewall lengths also allows for stress balancing during selective epitaxial refill.
    Type: Grant
    Filed: November 26, 2013
    Date of Patent: August 25, 2015
    Assignee: D3 Semiconductor LLC
    Inventors: Thomas E. Harrington, III, Robert Kuo-Chang Yang
  • Patent number: 8987778
    Abstract: Embodiments of the invention provide increased ESD protection suitable for high-voltage devices. In one embodiment, an internal DMOS circuit is placed in parallel with a lateral NPN ESD clamp. The clamp has both a high holding voltage, above the operating voltage of the DMOS circuit, and a high maximum current before breakdown. The discharge path of the clamp includes a high-voltage lightly doped well containing a low-voltage higher doped well. The dopant of both wells is the same type, and the interface between the two defines a graded junction. The emitter of the entire circuit is grounded and the collector is coupled to the voltage of the DMOS circuit.
    Type: Grant
    Filed: December 16, 2009
    Date of Patent: March 24, 2015
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Yue Zu, Hoang Phung Nguyen, Thomas E. Harrington, III
  • Publication number: 20140264343
    Abstract: A field effect device is disclosed that provides a reduced variation in on-resistance as a function of junction temperature. The field effect device, having a source junction, gate junction and drain junction, includes a resistive thin film adjacent the drain junction wherein the resistive thin film comprises a material having a negative temperature coefficient of resistance. The material is selected from one or more materials from the group consisting of doped polysilicon, amorphous silicon, silicon-chromium and silicon-nickel, where the material properties, such as thickness and doping level, are chosen to create a desired resistance and temperature profile for the field effect device. Temperature variation of on-resistance for the disclosed field effect device is reduced from the temperature variation for a similar field effect device without the resistive thin film.
    Type: Application
    Filed: March 13, 2014
    Publication date: September 18, 2014
    Applicant: D3 SEMICONDUCTOR LLC
    Inventor: Thomas E. Harrington, III
  • Publication number: 20140145240
    Abstract: Improvement of key electrical specifications of vertical semiconductor devices, usually found in the class of devices known as discrete semiconductors, has a direct impact on the performance achievement and power efficiency of the systems in which these devices are used. Imprecise vertical device specifications cause system builders to either screen incoming devices for their required specification targets or to design their system with lower performance or lower efficiency than desired. Disclosed is an architecture and method for achieving a desired target specification for a vertical semiconductor device. Precise trimming of threshold voltage improves targeting of both on-resistance and switching time. Precise trimming of gate resistance also improves targeting of switching time. Precise trimming of a device's effective width improves targeting of both on-resistance and current-carrying capability.
    Type: Application
    Filed: November 26, 2013
    Publication date: May 29, 2014
    Applicant: D3 Semiconductor LLC
    Inventor: Thomas E. Harrington, III
  • Publication number: 20140145245
    Abstract: A semiconductor field-effect device is disclosed that utilizes an octagonal or inverse-octagonal deep trench super-junction in combination with an octagonal or inverse-octagonal gate trench. The field-effect device achieves improved packing density, improved current density, and improved on resistance, while at the same time maintaining compatibility with the multiple-of-45°-angles of native photomask processing and having well characterized (010), (100) and (110) (and their equivalent) silicon sidewall surfaces for selective epitaxial refill and gate oxidation, resulting in improved scalability. By varying the relative length of each sidewall surface, devices with differing threshold voltages can be achieved without additional processing steps. Mixing trenches with varying sidewall lengths also allows for stress balancing during selective epitaxial refill.
    Type: Application
    Filed: November 26, 2013
    Publication date: May 29, 2014
    Applicant: D3 Semiconductor LLC
    Inventors: Thomas E. Harrington, III, Robert Kuo-Chang Yang
  • Patent number: 6306718
    Abstract: A polysilicon resistor is formed using a late implant process. Low dopant concentrations on the order of 6×1019 to 3.75×1020 have shown good results. with a reduced post anneal temperature. Both the first and second order temperature coefficients (TC1 and TC2) can then be adjusted. Using electrical trimming resistors can be produced with highly linear temperature characteristics. By varying the geometries of the resistors, low trimming threshold current densities and voltages can be used to produce good results.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: October 23, 2001
    Assignee: Dallas Semiconductor Corporation
    Inventors: Varun Singh, Tanmay Kumar, Thomas E. Harrington, III, Roy Austin Hensley, Allan T. Mitchell, Jack Gang Qian
  • Patent number: 5688722
    Abstract: A CMOS integrated circuit, in which the PMOS devices each include a buried channel region (26). The P+ source/drain regions (54) and (56) are separated from the channel region (26) by N-type lateral field isolating regions (58) and (60). Whenever a voltage negative enough to turn on the channel is applied, the isolating regions will be inverted by the electric fields from the comers of the gate. Thus, the value of the transistor's threshold voltage is not changed. However, these lateral field isolating regions provide an electric field modification which helps to minimize drain-induced barrier lowering, and thereby reduces the leakage current of the device in the off state. Preferably the lateral field isolating regions are formed by a doping which is maximal at the same depth (below the gate oxide) at which the threshold-voltage-adjust doping of the channel is maximal.The preferred CMOS process provides lateral field isolating regions on the PMOS devices, and also provides LDD regions on the NMOS devices.
    Type: Grant
    Filed: June 16, 1992
    Date of Patent: November 18, 1997
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III
  • Patent number: 5682051
    Abstract: A CMOS integrated circuit, in which the PMOS devices each include a buried channel region (26). The P+ source/drain regions (54) and (56) are separated from the channel region (26) by N-type lateral field isolating regions (58) and (60). Whenever a voltage negative enough to turn on the channel is applied, the isolating regions will be inverted by the electric fields from the comers of the gate. Thus, the value of the transistor's threshold voltage is not changed. However, these lateral field isolating regions provide an electric field modification which helps to minimize drain-induced barrier lowering, and thereby reduces the leakage current of the device in the off state. Preferably the lateral field isolating regions are formed by a doping which is maximal at the same depth (below the gate oxide) at which the threshold-voltage-adjust doping of the channel is maximal. The preferred CMOS process provides lateral field isolating regions on the PMOS devices, and also provides LDD regions on the NMOS devices.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 28, 1997
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III
  • Patent number: 5181091
    Abstract: A battery-backed integrated circuit, with a double diode structure connected to signal lines. In the double diode structure, a first junction is three-dimensionally enclosed by a second junction, so that minority carriers generated at the first junction will be collected at the second junction. Thus, when a negative transient voltage appears on the signal line, the first junction can be forward biassed to source the needed current from ground, with minimal minority carrier injection.
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: January 19, 1993
    Assignee: Dallas Semiconductor Corp.
    Inventors: Thomas E. Harrington, III, Robert D. Lee
  • Patent number: 5159426
    Abstract: A battery-backed integrated circuit, which receives battery power to maintain data (or logic states) when the system (external) power supply goes down. The battery power input is connected through a diode, so that the battery cannot be charged when the system power supply is active. The battery isolation diode is a junction diode, which is surrounded by a second junction. The battery junction collects minority carriers which will be generated when the battery protection diode is forward biased (i.e. when the integrated circuit is being powered from the battery). Otherwise, minority carriers can diffuse to other junctions, to cause leakage currents which can significantly degrade the lifetime of a low-powered device.
    Type: Grant
    Filed: December 20, 1990
    Date of Patent: October 27, 1992
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III
  • Patent number: 5122474
    Abstract: A CMOS integrated circuit, in which the PMOS devices each include a buried channel region (26). The P+ source/drain regions (54) and (56) are separated from the channel region (26) by N-type lateral field isolating regions (58) and (60). Whenever a voltage negative enough to turn on the channel is applied, the isolating regions will be inverted by the electric fields from the corners of the gate. Thus, the value of the transistor's threshold voltage is not changed. However, these lateral field isolating regions provide an electric field modification which helps to minimize drain-induced barrier lowering, and thereby reduces the leakage current of the device in the off state. Preferably the lateral field isolating regions are formed by a doping which is maximal at the same depth (below the gate oxide) at which the threshold-voltage-adjust doping of the channel is maximal.The preferred CMOS process provides lateral field isolating regions on the PMOS devices, and also provides LDD regions on the NMOS devices.
    Type: Grant
    Filed: September 27, 1991
    Date of Patent: June 16, 1992
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III
  • Patent number: 4980746
    Abstract: A battery-backed integrated circuit, which receives battery power to maintain data (or logic states) when the system (external) power supply goes down. The battery power input is connected through a diode, so that the battery cannot be charged when the system power supply is active. The battery isolation diode is a junction diode, which is surrounded by a second junction. The second junction collects minority carriers which will be generated when the battery protection diode is forward biased (i.e. when the integrated circuit is being powered from the battery). Otherwise, minority carriers can diffuse to other junctions, to cause leakage currents which can significantly degrade the lifetime of a low-powered device.
    Type: Grant
    Filed: April 28, 1989
    Date of Patent: December 25, 1990
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III
  • Patent number: 4950620
    Abstract: An integrated circuit which uses vertical current flow through arsenic-implanted oxide films to provide low-current loads. These load elements provide a compact four-transistor SRAM which has very simple fabrication and very low power consumption.
    Type: Grant
    Filed: September 30, 1988
    Date of Patent: August 21, 1990
    Assignee: Dallas Semiconductor Corp.
    Inventor: Thomas E. Harrington, III
  • Patent number: 4943537
    Abstract: A CMOS integrated circuit, in which the PMOS devices each include a buried channel region (26). The P+ source/drain regions (54) and (56) are separated from the channel region (26) by N-type lateral field isolating regions (58) and (60). Whenever a voltage negative enough to turn on the channel is applied, the isolating regions will be inverted by the electric fields from the corners of the gate. Thus, the value of the transistor's threshold voltage is not changed. However, these lateral field isolating regions provide an electric field modification which helps to minimize drain-induced barrier lowering, and thereby reduces the leakage current of the device in the off state. Preferably the lateral field isolating regions are formed by a doping which is maximal at the same depth (below the gate oxide) at which the threshold-voltage-adjust doping of the channel is maximal.The preferred CMOS process provides lateral field isolating regions on the PMOS devices, and also provides LDD regions on the NMOS devices.
    Type: Grant
    Filed: June 27, 1989
    Date of Patent: July 24, 1990
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III
  • Patent number: 4906588
    Abstract: An enclosed buried channel device includes a buried channel region (26) disposed under a gate electrode (24). Source and drain regions (54) and (56) are formed on either side of gate electrode (26). The source/drain regions (54) and (56) are separated from the various channel region (26) by isolating regions of N-type material (58) and (60), respectively. The isolating regions (58) and (60) are operable to be inverted during normal operation of the transistor when the transistor is conducting, but are operable to isolate fields on the drain side of the transistor from the buried channel region (26) to lower the leakage current of the device in the off state.
    Type: Grant
    Filed: June 23, 1988
    Date of Patent: March 6, 1990
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III
  • Patent number: 4862310
    Abstract: A battery protection device for preventing battery charging comprises a diode formed with a p+ region (36) within an N-type region (34). The diode is completely surrounded by a P-well (32) to prevent minority carrier injection from the N-type region (34) to the N-type substrate (30). The N-type region (34) is connected to the P-well (32) and to the substrate (30) through an electrical connection (43). By preventing minority carrier injection into the substrate (30), leakage through a parasitic transistor is prevented.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: August 29, 1989
    Assignee: Dallas Semiconductor Corporation
    Inventor: Thomas E. Harrington, III