Patents by Inventor Hiro Munekata

Hiro Munekata 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: 5296048
    Abstract: A new semiconductor material or compound and method for its manufacture is disclosed. The material or compound has the Formula III-V or IV which includes as part of the compound, a transition element or a rare earth element present in an amount sufficient to change the material or compound from a paramagnetic state to a locally ordered magnetic state. The material or compound is made by depositing III, and V or IV and a transition element or a rare earth element onto a substrate at conditions such that the transition element or rare earth element that is deposited on the substrate is not in equilibrium with the material or compound. By employing this technique new semiconductor materials or compounds can be made including Ga.sub.1-x Mn.sub.x As and In.sub.1-x Mn As where Mn is present in an amount greater than about 5.4.times.10.sup.20 cm.sup.-3.
    Type: Grant
    Filed: March 9, 1993
    Date of Patent: March 22, 1994
    Assignee: International Business Machines Corporation
    Inventors: Leroy L. Chang, Leo Esaki, Hiro Munekata, Hideo Ohno, Stephan vonMolnar
  • Patent number: 5294287
    Abstract: A new semiconductor material or compound and method for its manufacture is disclosed. The material or compound has the Formula III-V or IV which includes as part of the compound, a transition element or a rare earth element present in an amount sufficient to change the material or compound from a paramagnetic state to a locally ordered magnetic state. The material or compound is made by depositing III, and V or IV and a transition element or a rare earth element onto a substrate at conditions such that the transition element or rare earth element that is deposited on the substrate is not in equilibrium with the material or compound. By employing this technique new semiconductor materials or compounds can be made including Ga.sub.1-x Mn.sub.x As and In.sub.1-x Mn.sub.x As where Mn is present in an amount greater than about 5.4.times.10.sup.20 cm.sup.-3.
    Type: Grant
    Filed: August 2, 1991
    Date of Patent: March 15, 1994
    Assignee: International Business Machines Corporation
    Inventors: Leroy L. Chang, Leo Esaki, Hiro Munekata, Hideo Ohno, Stephan vonMolnar
  • Patent number: 5281543
    Abstract: Disclosed is a new method suitable for making highly integrated quantum wire arrays, quantum dot arrays in a single crystal compound semiconductor and FETs of less than 0.1 micron gate length. This makes it possible to construct a high-performance electronic device with high speed and low power consumption, using a combination of low-temperature-growth molecular beam epitaxy (LTG-MBE) and focused ion beam (FIB) implantation. The compound semiconductor (GaAs) epitaxial layers, which are made by LTG-MBE, are used as targets of Ga FIB implantation to make Ga wire or dot arrays. Precipitation of arsenic microcrystals, which are initially embedded in a single crystal GaAs layer and act as Schottky barriers, are typically observed in an LTG GaAs layer. A thermal annealing process, after implantation, changes the arsenic microcrystals to GaAs crystals if the arsenic microcrystals are in the region in which the Ga ions are implanted.
    Type: Grant
    Filed: July 13, 1992
    Date of Patent: January 25, 1994
    Assignee: International Business Machines Corporation
    Inventors: Tadashi Fukuzawa, Hiro Munekata
  • Patent number: 5170226
    Abstract: Disclosed is a new method suitable for making highly integrated quantum wire arrays, quantum dot arrays in a single crystal compound semiconductor and FETs of less than 0.1 micron gate length. This makes it possible to construct a high-performance electronic device with high speed and low power consumption, using a combination of low-temperature-growth molecular beam epitaxy (LTG-MBE) and focused ion beam (FIB) implantation. The compound semiconductor (GaAs) epitaxial layers, which are made by LTG-MBE, are used as targets of Ga FIB implantation to make Ga wire or dot arrays. Precipitation of arsenic microcrystals, which are initially embedded in a single crystal GaAs layer and act as Schottky barriers, are typically observed in an LTG GaAs layer. A thermal annealing process, after implantation, changes the arsenic microcrystals to GaAs crystals if the arsenic microcrystals are in the region in which the Ga ions are implanted.
    Type: Grant
    Filed: May 17, 1991
    Date of Patent: December 8, 1992
    Assignee: International Business Machines Corporation
    Inventors: Tadashi Fukuzawa, Hiro Munekata