Patents Assigned to Acorn Technologies, Inc.
  • Patent number: 9461167
    Abstract: An electrical device in which an interface layer is disposed in between and in contact with a conductor and a semiconductor.
    Type: Grant
    Filed: February 19, 2016
    Date of Patent: October 4, 2016
    Assignee: Acorn Technologies, Inc.
    Inventors: Daniel E. Grupp, Daniel J. Connelly
  • Patent number: 9425277
    Abstract: An electrical device in which an interface layer comprising arsenic is disposed between and in contact with a conductor and a semiconductor. In some cases, the interface layer may be a monolayer of arsenic.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: August 23, 2016
    Assignee: Acorn Technologies, Inc.
    Inventors: Daniel E. Grupp, Daniel J. Connelly
  • Publication number: 20160240678
    Abstract: An SOI wafer contains a compressively stressed buried insulator structure. In one example, the stressed buried insulator (BOX) may be formed on a host wafer by forming silicon oxide, silicon nitride and silicon oxide layers so that the silicon nitride layer is compressively stressed. Wafer bonding provides the surface silicon layer over the stressed insulator layer. Preferred implementations of the invention form MOS transistors by etching isolation trenches into a preferred SOI substrate having a stressed BOX structure to define transistor active areas on the surface of the SOI substrate. Most preferably the trenches are formed deep enough to penetrate through the stressed BOX structure and some distance into the underlying silicon portion of the substrate. The overlying silicon active regions will have tensile stress induced due to elastic edge relaxation.
    Type: Application
    Filed: February 8, 2013
    Publication date: August 18, 2016
    Applicant: Acorn Technologies, Inc.
    Inventors: Paul A. Clifton, R Stockton Gaines
  • Publication number: 20160234042
    Abstract: An OFDM system generates a channel estimate in the time domain for use in either a frequency domain equalizer or in a time domain equalizer. Preferably channel estimation is accomplished in the time domain using a locally generated reference signal. The channel estimator generates an initial estimate from a cross correlation between the time domain reference signal and an input signal input to the receiver and generates at least one successive channel estimate. Preferably the successive channel estimate is determined by vector addition (or subtraction) to the initial channel estimate. The at least one successive channel estimate reduces the minimum mean square error of the estimate with respect to a received signal.
    Type: Application
    Filed: May 13, 2014
    Publication date: August 11, 2016
    Applicant: Acorn Technologies, Inc.
    Inventor: Fernando Lopez de Victoria
  • Patent number: 9406798
    Abstract: An SOI wafer contains a compressively stressed buried insulator structure. In one example, the stressed buried insulator (BOX) may be formed on a host wafer by forming silicon oxide, silicon nitride and silicon oxide layers so that the silicon nitride layer is compressively stressed. Wafer bonding provides the surface silicon layer over the stressed insulator layer. Preferred implementations of the invention form MOS transistors by etching isolation trenches into a preferred SOI substrate having a stressed BOX structure to define transistor active areas on the surface of the SOI substrate. Most preferably the trenches are formed deep enough to penetrate through the stressed BOX structure and some distance into the underlying silicon portion of the substrate. The overlying silicon active regions will have tensile stress induced due to elastic edge relaxation.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: August 2, 2016
    Assignee: Acorn Technologies, Inc.
    Inventors: Paul A. Clifton, R. Stockton Gaines
  • Patent number: 9362376
    Abstract: Techniques for reducing the specific contact resistance of metal-semiconductor (group IV) junctions by interposing a monolayer of group V or group III atoms at the interface between the metal and the semiconductor, or interposing a bi-layer made of one monolayer of each, or interposing multiple such bi-layers. The resulting low specific resistance metal-group IV semiconductor junctions find application as a low resistance electrode in semiconductor devices including electronic devices (e.g., transistors, diodes, etc.) and optoelectronic devices (e.g., lasers, solar cells, photodetectors, etc.) and/or as a metal source and/or drain region (or a portion thereof) in a field effect transistor (FET). The monolayers of group III and group V atoms are predominantly ordered layers of atoms formed on the surface of the group IV semiconductor and chemically bonded to the surface atoms of the group IV semiconductor.
    Type: Grant
    Filed: October 18, 2012
    Date of Patent: June 7, 2016
    Assignee: Acorn Technologies, Inc.
    Inventors: Walter A Harrison, Paul A. Clifton, Andreas Goebel, R. Stockton Gaines
  • Patent number: 9319260
    Abstract: An OFDM receiver receives OFDM symbols in the frequency domain and comb filters and then punctures the OFDM symbols to leave symbols with actual pilot information and with null values at the data symbols. The receiver provides the punctured OFDM symbols to an OFDM symbol queue. A virtual pilot interpolator is coupled to the punctured OFDM symbol storage to generate virtual pilot information introduced to OFDM symbols. The interpolator may be a two dimensional Wiener filter. The receiver also includes a time domain channel estimator that processes a first OFDM symbol including virtual pilot information to generate a channel impulse response for the first OFDM symbol. A frequency equalizer equalizes the OFDM symbol in response to the channel impulse response for the first OFDM symbol.
    Type: Grant
    Filed: October 27, 2014
    Date of Patent: April 19, 2016
    Assignee: Acorn Technologies, Inc.
    Inventors: Steven C Thompson, Fernando Lopez de Victoria
  • Patent number: 9270083
    Abstract: Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.
    Type: Grant
    Filed: April 28, 2015
    Date of Patent: February 23, 2016
    Assignee: Acorn Technologies, Inc.
    Inventors: Paul A. Clifton, Andreas Goebel, R. Stockton Gaines
  • Patent number: 9209261
    Abstract: An electrical device in which an interface layer is disposed in between and in contact with a conductor and a semiconductor.
    Type: Grant
    Filed: June 18, 2015
    Date of Patent: December 8, 2015
    Assignee: Acorn Technologies, Inc.
    Inventors: Daniel E. Grupp, Daniel J. Connelly
  • Publication number: 20150333933
    Abstract: An OFDM system generates a channel estimate in the time domain for use in either a frequency domain equalizer or in a time domain equalizer. Preferably channel estimation is accomplished in the time domain using a locally generated reference signal. The channel estimator generates an initial estimate from a cross correlation between the time domain reference signal and an input signal input to the receiver and generates at least one successive channel estimate. Preferably the successive channel estimate is determined by vector addition (or subtraction) to the initial channel estimate. The at least one successive channel estimate reduces the minimum mean square error of the estimate with respect to a received signal.
    Type: Application
    Filed: May 13, 2014
    Publication date: November 19, 2015
    Applicant: Acorn Technologies, Inc.
    Inventor: Fernando Lopez de Victoria
  • Patent number: 9154337
    Abstract: An OFDM receiver generates an initial channel impulse response in response to a received OFDM signal. The receiver determines the time span within the initial channel impulse response in which significant paths are present. An intermediate channel impulse response estimator identifies paths within the initial channel impulse response and generates an improved intermediate channel impulse response. A channel impulse response estimator performs a second non-linear process to generate a channel impulse response. An equalizer responds to the channel impulse response and the OFDM symbol to equalize the OFDM symbol. Metrics are generated that can be used for effectively stopping the second iterative non-linear process.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: October 6, 2015
    Assignee: Acorn Technologies, Inc.
    Inventors: Steven C Thompson, Roee Kalinksy, Fernando Lopez de Victoria
  • Patent number: 9094821
    Abstract: A software upgrade application can be downloaded to a handset to selectively enable enhanced functionality physical layer circuitry. In a particular implementation, an OFDM handset or other portable modem includes selectively enabled time domain channel estimation circuitry. An upgrade application within the handset is activated. The handset is checked to confirm compatibility with the enhanced functionality and the upgrade application is checked to confirm its authenticity. The upgrade application then activates the enhanced functionality within the physical layer of the device.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: July 28, 2015
    Assignee: Acorn Technologies, Inc.
    Inventors: Steven J. Caliguri, Steven C. Thompson
  • Patent number: 9059201
    Abstract: Processes for making field effect transistors relax a buried stressor layer to induce strain in a silicon surface layer above the buried stressor layer. The buried stressor layer is relaxed and the surface layer is strained by implantation into at least the buried stressor layer, preferably on both sides of a portion of the surface layer that is to be stressed. For example, implanting ions through the surface silicon layer on either side of the gate structure of the preferred FET implementation into an underlying stressor layer can induce strain in a channel region of the FET. This process can begin with a silicon or silicon-on-insulator substrate with a buried silicon germanium layer having an appropriate thickness and germanium concentration. Other stressor materials can be used.
    Type: Grant
    Filed: January 15, 2013
    Date of Patent: June 16, 2015
    Assignee: Acorn Technologies, Inc.
    Inventor: Paul A. Clifton
  • Patent number: 9036672
    Abstract: Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.
    Type: Grant
    Filed: April 18, 2014
    Date of Patent: May 19, 2015
    Assignee: Acorn Technologies, Inc.
    Inventors: Paul A. Clifton, Andreas Goebel, R. Stockton Gaines
  • Patent number: 9029686
    Abstract: Improved silicon solar cells, silicon image sensors and like photosensitive devices are made to include strained silicon at or sufficiently near the junctions or other active regions of the devices to provide increased sensitivity to longer wavelength light. Strained silicon has a lower band gap than conventional silicon. One method of making a solar cell that contains tensile strained silicon etches a set of parallel trenches into a silicon wafer and induces tensile strain in the silicon fins between the trenches. The method may induce tensile strain in the silicon fins by filling the trenches with compressively strained silicon nitride or silicon oxide. A deposited layer of compressively strained silicon nitride adheres to the walls of the trenches and generates biaxial tensile strain in the plane of adjacent silicon fins.
    Type: Grant
    Filed: April 25, 2013
    Date of Patent: May 12, 2015
    Assignee: Acorn Technologies, Inc.
    Inventor: Paul A Clifton
  • Patent number: 9031123
    Abstract: A receiver performs interference mitigation under blind or semi-blind conditions using diversity present in the signal of interest or in the interferer. A first path interference mitigation procedure extracts training information from received signals, performs interference mitigation on the training information and estimates the channel. The second path interference mitigation procedure uses data extracted from the received signal and the channel estimate to perform interference mitigation. Each interference mitigation process can take the form of a lossy compression followed by decompression.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: May 12, 2015
    Assignee: Acorn Technologies, Inc.
    Inventor: Fernando Lopez de Victoria
  • Publication number: 20150043629
    Abstract: An OFDM receiver receives OFDM symbols in the frequency domain and comb filters and then punctures the OFDM symbols to leave symbols with actual pilot information and with null values at the data symbols. The receiver provides the punctured OFDM symbols to an OFDM symbol queue. A virtual pilot interpolator is coupled to the punctured OFDM symbol storage to generate virtual pilot information introduced to OFDM symbols. The interpolator may be a two dimensional Wiener filter. The receiver also includes a time domain channel estimator that processes a first OFDM symbol including virtual pilot information to generate a channel impulse response for the first OFDM symbol. A frequency equalizer equalizes the OFDM symbol in response to the channel impulse response for the first OFDM symbol.
    Type: Application
    Filed: October 27, 2014
    Publication date: February 12, 2015
    Applicant: Acorn Technologies, Inc.
    Inventors: Steven C. Thompson, Fernando Lopez de Victoria
  • Patent number: 8916437
    Abstract: A transistor having at least one passivated Schottky barrier to a channel includes an insulated gate structure on a p-type substrate in which the channel is located beneath the insulated gate structure. The channel and the insulated gate structure define a first and second undercut void regions that extend underneath the insulated gate structure toward the channel from a first and a second side of the insulated gate structure, respectively. A passivation layer is included on at least one exposed sidewall surface of the channel, and metal source and drain terminals are located on respective first and second sides of the channel, including on the passivation layer and within the undercut void regions beneath the insulated gate structure. At least one of the metal source and drain terminals comprises a metal that has a work function near a valence band of the p-type substrate.
    Type: Grant
    Filed: February 1, 2013
    Date of Patent: December 23, 2014
    Assignee: Acorn Technologies, Inc.
    Inventors: Daniel E. Grupp, Daniel J. Connelly
  • Publication number: 20140369372
    Abstract: Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.
    Type: Application
    Filed: April 18, 2014
    Publication date: December 18, 2014
    Applicant: Acorn Technologies, Inc.
    Inventors: Paul A. Clifton, Andreas Goebel, R. Stockton Gaines
  • Patent number: 8897353
    Abstract: An OFDM receiver receives OFDM symbols in the frequency domain and comb filters and then punctures the OFDM symbols to leave symbols with actual pilot information and with null values at the data symbols. The receiver provides the punctured OFDM symbols to an OFDM symbol queue. A virtual pilot interpolator is coupled to the punctured OFDM symbol storage to generate virtual pilot information introduced to OFDM symbols. The interpolator may be a two dimensional Wiener filter. The receiver also includes a time domain channel estimator that processes a first OFDM symbol including virtual pilot information to generate a channel impulse response for the first OFDM symbol. A frequency equalizer equalizes the OFDM symbol in response to the channel impulse response for the first OFDM symbol.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: November 25, 2014
    Assignee: Acorn Technologies, Inc.
    Inventors: Steven C Thompson, Fernando Lopez de Victoria