Patents by Inventor Alexander B. Hoefler

Alexander B. Hoefler 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: 20110267869
    Abstract: A memory system including a one time programmable (OTP) memory is provided. The memory system further includes a write enable verification circuit including an asymmetric inverter stage and a symmetric inverter stage coupled at a node. The write enable verification circuit is configured to receive a write enable signal. When the write enable signal changes from a first voltage level to a second voltage level, a voltage at the node changes at a first rate and wherein when the write enable signal changes from the second voltage level to the first voltage level, the voltage at the node changes at a second rate higher than the first rate. The write enable verification circuit is further configured to generate a verified write enable signal for enabling programming of the OTP memory.
    Type: Application
    Filed: April 30, 2010
    Publication date: November 3, 2011
    Inventors: Alexander B. Hoefler, Mohamed S. Moosa
  • Patent number: 7787323
    Abstract: A detect circuit may be used to detect one or more characteristics corresponding to the fuse being programmed. When the one or more characteristics of the fuse being programmed reach the desired states or values, the programming of the fuse is discontinued. Thus, the programming duration for each fuse is customized for each fuse. As a result, for some embodiments, there may be fewer fuses that have been over-programmed. In addition, for some embodiments, the range of impedances of the programmed fuses have a narrower distribution of impedances due to the use of the detect circuit.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: August 31, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Lawrence N. Herr, Alexander B. Hoefler
  • Publication number: 20100198896
    Abstract: A random number generator includes a first one time programmable (OTP) element and a second OTP element. The first OTP element and second OTP element have a first distribution of probable values for an electrical characteristic when unprogrammed and a second distribution of probable values when programmed. A programming circuit applies a programming signal to the first OTP element and to the second OTP element that causes the first OTP element to switch from being unprogrammed to being programmed and having a first value for its electrical characteristic and the second OTP element to switch from being unprogrammed to being programmed and having a second value for its electrical characteristic. A sense amplifier provides an output signal at a first logic state when the first value exceeds the second value and at a second logic state when the second value exceeds the first value.
    Type: Application
    Filed: January 30, 2009
    Publication date: August 5, 2010
    Inventor: Alexander B. Hoefler
  • Patent number: 7733711
    Abstract: A memory has an array of memory cells, a word line driver, a sense amplifier, and a sense enable circuit. Each memory cell has a coupling transistor for coupling a storage portion to a bit line. The coupling transistors have an average threshold voltage and a maximum threshold voltage. The word line driver is coupled to the array and is for enabling a selected row of memory cells in the array. The sense amplifier detects a state of a memory cell in the selected row in response to a sense enable signal. The sense enable circuit provides the sense enable signal at a time based on the maximum threshold voltage. This timing enables the sense amplifier sufficiently late for low temperature operation while providing for faster operation at high temperature than would normally be achieved using just the average threshold voltage in providing timing of the sense enable signal.
    Type: Grant
    Filed: September 8, 2008
    Date of Patent: June 8, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: James D. Burnett, Alexander B. Hoefler
  • Patent number: 7678620
    Abstract: A method for making a one time programmable (OTP) memory array includes providing a wafer comprising a buried insulator layer and a semiconductor layer over the buried insulator layer and forming a plurality of bit lines in the semiconductor layer. Each of the plurality of bit lines comprise a portion of the semiconductor layer and the plurality of bit lines are separated from each other by isolation regions formed in the semiconductor layer. The method further includes forming an anti-fuse dielectric layer over and in physical contact with the plurality of bit lines and the isolation regions, and forming a plurality of word lines over and in physical contact with the anti-fuse dielectric layer.
    Type: Grant
    Filed: October 5, 2006
    Date of Patent: March 16, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Alexander B. Hoefler
  • Publication number: 20100061162
    Abstract: A memory has an array of memory cells, a word line driver, a sense amplifier, and a sense enable circuit. Each memory cell has a coupling transistor for coupling a storage portion to a bit line. The coupling transistors have an average threshold voltage and a maximum threshold voltage. The word line driver is coupled to the array and is for enabling a selected row of memory cells in the array. The sense amplifier detects a state of a memory cell in the selected row in response to a sense enable signal. The sense enable circuit provides the sense enable signal at a time based on the maximum threshold voltage. This timing enables the sense amplifier sufficiently late for low temperature operation while providing for faster operation at high temperature than would normally be achieved using just the average threshold voltage in providing timing of the sense enable signal.
    Type: Application
    Filed: September 8, 2008
    Publication date: March 11, 2010
    Inventors: James D. Burnett, Alexander B. Hoefler
  • Patent number: 7583554
    Abstract: The fuse array described herein is very compact and uses little semiconductor area because of its crosspoint architecture. The disclosed crosspoint architecture reduces the number of conductors that must be run horizontally or vertically through each bit cell. As a result, the area required for each bit cell is significantly reduced. In one embodiment, a selected set of voltages on various wordlines and bitlines are used to program the fuses to produce programmed fuses having a tighter distribution of impedances. Similarly, a selected set of voltages on various wordlines and bitlines are used to read the fuses.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: September 1, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Alexander B. Hoefler
  • Patent number: 7575958
    Abstract: A programmable fuse and method of formation utilizing a layer of silicon germanium (SiGe) (e.g. monocrystalline) as a thermal insulator to contain heat generated during programming. The programmable fuse, in some examples, may be devoid of any dielectric materials between a conductive layer and a substrate. In one example, the conductive layer serves as programmable material, that in a low impedance state, electrically couples conductive structures. A programming current is applied to the programmable material to modify the programmable material to place the fuse in a high impedance state.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: August 18, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Alexander B. Hoefler, Marius K. Orlowski
  • Patent number: 7560965
    Abstract: A circuit has a master latch having an input for receiving an input data signal, and an output. A slave latch has a first input coupled to the output of the master latch, and an output for providing an output data signal. A non-volatile storage element stores a predetermined value. The non-volatile storage element has an output coupled to the first input of the slave latch. The output data signal corresponds to one of either the input data signal or the predetermined value stored by the non-volatile storage element in response to a control signal.
    Type: Grant
    Filed: April 30, 2007
    Date of Patent: July 14, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jeffrey W. Waldrip, Alexander B. Hoefler
  • Patent number: 7518177
    Abstract: A semiconductor storage device floats the gate of a conventional transistor between two capacitors to store a logic state which can be utilized to store the condition of a circuit such as a latching type circuit such as a flip-flop or register prior to a power down operation to save power. The gate and first terminals of the two capacitors preferably share the same conductive line such as a polysilicon segment. A second transistor and a second set of capacitors store the complementary state of the logic state so that complementary signals are provided for detecting the stored logic state. After the time for power down has ended, the state of the semiconductor storage device made up of the two transistors and four capacitors is sensed, and the detected logic state is loaded back into the latching type circuit.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: April 14, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Alexander B. Hoefler
  • Publication number: 20080265962
    Abstract: A circuit has a master latch having an input for receiving an input data signal, and an output. A slave latch has a first input coupled to the output of the master latch, and an output for providing an output data signal. A non-volatile storage element stores a predetermined value. The non-volatile storage element has an output coupled to the first input of the slave latch. The output data signal corresponds to one of either the input data signal or the predetermined value stored by the non-volatile storage element in response to a control signal.
    Type: Application
    Filed: April 30, 2007
    Publication date: October 30, 2008
    Inventors: Jeffrey W. Waldrip, Alexander B. Hoefler
  • Publication number: 20080266994
    Abstract: A detect circuit may be used to detect one or more characteristics corresponding to the fuse being programmed. When the one or more characteristics of the fuse being programmed reach the desired states or values, the programming of the fuse is discontinued. Thus, the programming duration for each fuse is customized for each fuse. As a result, for some embodiments, there may be fewer fuses that have been over-programmed. In addition, for some embodiments, the range of impedances of the programmed fuses have a narrower distribution of impedances due to the use of the detect circuit.
    Type: Application
    Filed: April 27, 2007
    Publication date: October 30, 2008
    Inventors: Lawrence N. Herr, Alexander B. Hoefler
  • Patent number: 7444557
    Abstract: A memory not only uses redundant cells but also redundant references to reduce the likelihood of a failure. In one approach a failure in a reference can cause both the primary cell as well as the redundant cell to be ineffective. To overcome this potential problem two references for each bit are employed. In one form, the primary cell of a first bit is compared to one reference and the redundant cell of the first bit is compared to another reference. The primary and redundant cell of a second bit can use these two references as well. In another aspect, two references are placed in parallel for both the primary and redundant cell of the bit.
    Type: Grant
    Filed: July 15, 2004
    Date of Patent: October 28, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Alexander B. Hoefler, Qadeer A. Qureshi
  • Patent number: 7432547
    Abstract: A semiconductor device (30) comprises an underlying insulating layer (34), an overlying insulating layer (42) and a charge storage layer (36) between the insulating layers (34, 42). The charge storage layer (36) and the overlying insulating layer (42) form an interface, where at least a majority of charge in the charge storage layer (36) is stored. This can be accomplished by forming a charge storage layer (36) with different materials such as silicon and silicon germanium layers or n-type and p-type material layers, in one embodiment. In another embodiment, the charge storage layer (36) comprises a dopant that is graded. By storing at least a majority of the charge at the interface between the charge storage layer (36) and the overlying insulating layer (42), the leakage of charge through the underlying insulating layer is decreased allowing for a thinner underlying insulating layer (34) to be used.
    Type: Grant
    Filed: February 13, 2004
    Date of Patent: October 7, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Frank K. Baker, Jr., Paul A. Ingersoll, Alexander B. Hoefler
  • Publication number: 20080212387
    Abstract: The fuse array described herein is very compact and uses little semiconductor area because of its crosspoint architecture. The disclosed crosspoint architecture reduces the number of conductors that must be run horizontally or vertically through each bit cell. As a result, the area required for each bit cell is significantly reduced. In one embodiment, a selected set of voltages on various wordlines and bitlines are used to program the fuses to produce programmed fuses having a tighter distribution of impedances. Similarly, a selected set of voltages on various wordlines and bitlines are used to read the fuses.
    Type: Application
    Filed: March 2, 2007
    Publication date: September 4, 2008
    Inventor: Alexander B. Hoefler
  • Publication number: 20080212388
    Abstract: The fuse array described herein is very compact and uses little semiconductor area because of its crosspoint architecture. The disclosed crosspoint architecture reduces the number of conductors that must be run horizontally or vertically through each bit cell. As a result, the area required for each bit cell is significantly reduced. In one embodiment, a selected set of voltages on various wordlines and bitlines are used to program the fuses to produce programmed fuses having a tighter distribution of impedances. Similarly, a selected set of voltages on various wordlines and bitlines are used to read the fuses.
    Type: Application
    Filed: March 2, 2007
    Publication date: September 4, 2008
    Inventor: Alexander B. Hoefler
  • Patent number: 7369452
    Abstract: A device having an OTP memory is disclosed. A program state of the OTP device is stored at a fuse that is connected in series between a first node and a latch. During a program mode, the first node is electrically connected to a program voltage. During a read mode, the first node is electrically connected to ground, whereby a first divided voltage is generated at a first node of the latch.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: May 6, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Prashant U. Kenkare, Jeffrey W. Waldrip, Alexander B. Hoefler
  • Publication number: 20080085574
    Abstract: A method for making a one time programmable (OTP) memory array includes providing a wafer comprising a buried insulator layer and a semiconductor layer over the buried insulator layer and forming a plurality of bit lines in the semiconductor layer. Each of the plurality of bit lines comprise a portion of the semiconductor layer and the plurality of bit lines are separated from each other by isolation regions formed in the semiconductor layer. The method further includes forming an anti-fuse dielectric layer over and in physical contact with the plurality of bit lines and the isolation regions, and forming a plurality of word lines over and in physical contact with the anti-fuse dielectric layer.
    Type: Application
    Filed: October 5, 2006
    Publication date: April 10, 2008
    Inventor: Alexander B. Hoefler
  • Patent number: 7312129
    Abstract: A semiconductor process and apparatus use a predetermined sequence of patterning and etching steps to etch a gate stack (62) formed over a substrate (11) and a first spacer structure (42), thereby forming etched gate structures (72, 74) that are physically separated from one another but that control a substrate channel (71) subsequently defined in the substrate (11) by source/drain regions (82, 102, 84, 104) that are implanted around the etched gate structures (72, 74). Depending on how the first spacer structure (42) is positioned and configured, the channel (71) may be controlled to provide either a logical AND gate (100) or logical OR gate (200) functionality.
    Type: Grant
    Filed: January 25, 2006
    Date of Patent: December 25, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Sinan Goktepeli, Alexander B. Hoefler, Marius K. Orlowski
  • Patent number: 7289352
    Abstract: A semiconductor storage device floats the gate of a conventional transistor between two capacitors to store a logic state which can be utilized to store the condition of a circuit such as a latching type circuit such as a flip-flop or register prior to a power down operation to save power. The gate and first terminals of the two capacitors preferably share the same conductive line such as a polysilicon segment. A second transistor and a second set of capacitors store the complementary state of the logic state so that complementary signals are provided for detecting the stored logic state. After the time for power down has ended, the state of the semiconductor storage device made up of the two transistors and four capacitors is sensed, and the detected logic state is loaded back into the latching type circuit.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: October 30, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Alexander B. Hoefler