Patents by Inventor Steven T. Harshfield

Steven T. Harshfield 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: 5851882
    Abstract: A cost-competitive, dense, CMOS compatible ZPROM memory array design and method of manufacture is disclosed. The method of manufacture includes a novel method for forming extremely thin diodes and thin strips of other materials such as conductors by using oxide spacers as an etching mask.
    Type: Grant
    Filed: May 6, 1996
    Date of Patent: December 22, 1998
    Assignee: Micron Technology, Inc.
    Inventor: Steven T. Harshfield
  • Patent number: 5818749
    Abstract: A memory array using structure changing memory elements in a reverse biased diode array is disclosed. A memory cell is programmed and read by reverse biasing the diode to overcome the diode's breakdown voltage. The disclosed reversed biased diode array exhibits much less substrate current leakage than a similar forward biased diode array.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: October 6, 1998
    Assignee: Micron Technology, Inc.
    Inventor: Steven T. Harshfield
  • Patent number: 5814527
    Abstract: A method for fabricating an ultra-small pore or contact for use in chalcogenide memory cells specifically and in semiconductor devices generally in which disposable spacers are utilized to fabricate ultra-small pores or contacts. The pores thus defined have minimum lateral dimensions ranging from approximately 500 to 4000 Angstroms. The pores thus defined may then be used to fabricate a chalcogenide memory cell or other semiconductor devices.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: September 29, 1998
    Assignee: Micron Technology, Inc.
    Inventors: Graham R. Wolstenholme, Steven T. Harshfield, Raymond A. Turi, Fernando Gonzalez, Guy T. Blalock, Donwon Park
  • Patent number: 5719418
    Abstract: A structure and process for forming a contact to a semiconductor substrate on a semiconductor device comprises the step of forming a patterned mask over a semiconductor substrate and over a field oxide region, then etching the semiconductor substrate and the field oxide region to form a trench. The trench comprises a bottom and a first sidewall consisting of silicon and a second sidewall comprising field oxide. The etching step removes a part of a doped region in the substrate. Next, a blanket nitride layer and a blanket oxide layer is formed over the substrate, and a spacer etch is performed on the nitride and oxide layer leaving nitride and oxide over the first and second sidewalls. The trench bottom is oxidized to form a layer of oxide over the bottom of the trench thereby insulating the trench bottom, and the oxide encroaches under the nitride and oxide on the sidewalls to join with the field oxide.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: February 17, 1998
    Assignee: Micron Technology, Inc.
    Inventors: Nanseng Jeng, Steven T. Harshfield, Paul J. Schuele
  • Patent number: 5646879
    Abstract: The present invention teaches a memory comprising an array of memory cells. Each cell of the array in the memory comprises a bus, and a diode, preferably a zener diode, having a substantially low breakdown voltage. Further, each cell comprises a programmable element, preferably an antifuse, for selectively coupling the diode with the bus.
    Type: Grant
    Filed: December 1, 1994
    Date of Patent: July 8, 1997
    Assignee: Micron Technology, Inc.
    Inventor: Steven T. Harshfield
  • Patent number: 5612558
    Abstract: Disclosed is a method of growing hemispherical grained silicon (HSG silicon) over a conductive seed layer. In a preferred embodiment, a contact window is etched in an insulating layer to expose a circuit node, such as an active area of a substrate or a contact plug leading to an active area. A layer of titanium nitride is deposited over the insulating layer and into the contact window. The titanium nitride (TiN) serves as the seed layer for HSG silicon growth to follow. Polysilicon is deposited and grows around nucleation sites on the TiN surface. The TiN provides both electrical and mechanical support for the HSG silicon. Additionally, as TiN is an effective diffusion barrier, the HSG silicon may be heavily doped without undue risk of dopant diffusion to the active area.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: March 18, 1997
    Assignee: Micron Technology, Inc.
    Inventor: Steven T. Harshfield
  • Patent number: 5492853
    Abstract: A structure and process for forming a contact to a semiconductor substrate on a semiconductor device comprises the step of forming a patterned mask over a semiconductor substrate and over a field oxide region, then etching the semiconductor substrate and the field oxide region to form a trench. The trench comprises a bottom and a first sidewall consisting of silicon and a second sidewall comprising field oxide. The etching step removes a part of a doped region in the substrate. Next, a blanket nitride layer and a blanket oxide layer is formed over the substrate, and a spacer etch is performed on the nitride and oxide layer leaving nitride and oxide over the first and second sidewalls. The trench bottom is oxidized to form a layer of oxide over the bottom of the trench thereby insulating the trench bottom, and the oxide encroaches under the nitride and oxide on the sidewalls to join with the field oxide.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: February 20, 1996
    Assignee: Micron Semiconductor, Inc.
    Inventors: Nanseng Jeng, Steven T. Harshfield, Paul J. Schuele
  • Patent number: 5379250
    Abstract: The present invention teaches a memory comprising an array of memory cells. Each cell of the array in the memory comprises a bus, and a diode, preferably a zener diode, having a substantially low breakdown voltage. Further, each cell comprises a programmable element, preferably an antifuse, for selectively coupling the diode with the bus.
    Type: Grant
    Filed: August 20, 1993
    Date of Patent: January 3, 1995
    Assignee: Micron Semiconductor, Inc.
    Inventor: Steven T. Harshfield