Patents Assigned to ACORN SEMI, LLC
  • Patent number: 10727647
    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: December 7, 2018
    Date of Patent: July 28, 2020
    Assignee: Acorn Semi, LLC
    Inventors: Paul A. Clifton, Andreas Goebel, R. Stockton Gaines
  • Patent number: 10580896
    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: August 20, 2018
    Date of Patent: March 3, 2020
    Assignee: ACORN SEMI, LLC
    Inventors: Paul A. Clifton, R. Stockton Gaines
  • Patent number: 10553695
    Abstract: An electrical contact structure (an MIS contact) includes one or more conductors (M-Layer), a semiconductor (S-Layer), and an interfacial dielectric layer (I-Layer) of less than 4 nm thickness disposed between and in contact with both the M-Layer and the S-Layer. The I-Layer is an oxide of a metal or a semiconductor. The conductor of the M-Layer that is adjacent to and in direct contact with the I-Layer is a metal oxide that is electrically conductive, chemically stable and unreactive at its interface with the I-Layer at temperatures up to 450° C. The electrical contact structure has a specific contact resistivity of less than or equal to approximately 10?5-10?7 ?-cm2 when the doping in the semiconductor adjacent the MIS contact is greater than approximately 2×1019 cm?3 and less than approximately 10?8 ?-cm2 when the doping in the semiconductor adjacent the MIS contact is greater than approximately 1020 cm?3.
    Type: Grant
    Filed: October 30, 2018
    Date of Patent: February 4, 2020
    Assignee: Acorn Semi, LLC
    Inventors: Paul A. Clifton, Andreas Goebel
  • Patent number: 10505047
    Abstract: A nanowire transistor includes undoped source and drain regions electrically coupled with a channel region. A source stack that is electrically isolated from a gate conductor includes an interfacial layer and a source conductor, and is coaxially wrapped completely around the source region, extending along at least a portion of the source region. A Schottky barrier between the source conductor and the source region is a negative Schottky barrier and a concentration of free charge carriers is induced in the semiconductor source region.
    Type: Grant
    Filed: November 28, 2018
    Date of Patent: December 10, 2019
    Assignee: ACORN SEMI, LLC
    Inventors: Paul A. Clifton, Andreas Goebel, Walter A. Harrison
  • Patent number: 10505005
    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: August 23, 2017
    Date of Patent: December 10, 2019
    Assignee: ACORN SEMI, LLC
    Inventors: Walter A. Harrison, Paul A. Clifton, Andreas Goebel, R. Stockton Gaines