Patents by Inventor Toshiaki Iwafuchi

Toshiaki Iwafuchi 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: 20030150843
    Abstract: Disclosed are a crystal layer separation method capable of separating a crystal layer formed on a substrate therefrom without occurrence of any crack, and a laser irradiation method used therefor, and a method of fabricating devices using the same. The crystal layer separation method includes the step of separating a crystal layer made from a GaN based compound formed on a sapphire substrate therefrom by irradiating the crystal layer with a laser beam from the back surface of the substrate, wherein the crystal layer is irradiated with the laser beam in a line-shape. In this method, an irradiation width of the laser beam is preferably equal to or less than a thickness of the crystal layer, and the laser beam preferably has a light intensity distribution smoothened in the width direction.
    Type: Application
    Filed: December 3, 2002
    Publication date: August 14, 2003
    Applicant: Sony Corporation
    Inventors: Masato Doi, Toshiaki Iwafuchi, Toyoharu Oohata
  • Publication number: 20030087476
    Abstract: A first adhesive layer is provided on a base substrate, and multiple devices are arranged on the first adhesive layer. The first adhesive layer is irradiated with laser light from the back side of the base substrate, only at positions corresponding to the devices to be transferred, by use of a mask, whereby the adhesive force of the first adhesive layer is lowered only at these positions, and only these devices are made releasable from the base substrate. A transfer substrate provided with a second adhesive layer and the base substrate are so disposed that the devices and the second adhesive layer are opposite to each other and pressed against each other. When the transfer substrate is stripped from the base substrate, only the devices to be transferred are selectively transferred onto the transfer substrate.
    Type: Application
    Filed: September 6, 2002
    Publication date: May 8, 2003
    Inventors: Toyoharu Oohata, Toshiaki Iwafuchi, Hisashi Ohba
  • Publication number: 20030034120
    Abstract: A device transferring method and a device arraying method are provided for readily transferring a number of devices from a first substrate to a second substrate such that the devices are enlargedly spaced from each other with a pitch larger than an array pitch of the devices arrayed on the first substrate.
    Type: Application
    Filed: July 31, 2002
    Publication date: February 20, 2003
    Inventors: Yoshiyuki Yanagisawa, Toshiaki Iwafuchi, Masaru Minami, Kunihiko Hayashi
  • Publication number: 20030025657
    Abstract: A light emitting unit represented by an image display unit includes chips, each of which is formed by burying a light emitting device such as a GaN based semiconductor light emitting device in a resin, wherein external terminals connected to the light emitting device buried in each chip are provided on the chip, and a drive control device such as a pixel transistor for controlling the drive of the light emitting device are connected to the external terminals in a state being at least partially overlapped to the chip. Such an image display unit is advantageous in improving a device density such as a pixel density, enhancing the connection reliability by increasing the diameters of via-holes for wiring without excessively reducing the size of each chip, improving the fabrication yield, facilitating the handling of the chip (or device) at the time of bonding by increasing the apparent area of the chip (or device), and lowering the required specification in terms of alignment accuracy of the chip (or device).
    Type: Application
    Filed: August 2, 2002
    Publication date: February 6, 2003
    Inventor: Toshiaki Iwafuchi
  • Publication number: 20030011377
    Abstract: A method of repairing a defective one of devices mounted on substrate is provided. Devices are arrayed on a substrate and electrically connected to wiring lines connected to a drive circuit, to be thus mounted on the substrate. The devices mounted on the substrate are then subjected to an emission test. If a defective device is detected in this test, a repair device is mounted at a position corresponding to a position of the defective device. At this time, after wiring lines connected to the defective device are cut off, the repair device is electrically connected to portions of the wiring lines, the portions of the wiring lines being located at positions nearer to the drive circuit side than the cut-off positions of the wiring lines.
    Type: Application
    Filed: June 6, 2002
    Publication date: January 16, 2003
    Inventors: Toyoharu Oohata, Toshiaki Iwafuchi, Hisashi Ohba
  • Publication number: 20020171090
    Abstract: A display device is formed by burying at least part of a light emitting device in an insulating material, wherein a drive electrode for the light emitting device is formed so as to be extracted on a surface of the insulating material. A display unit is produced by two-dimensionally arraying such light emitting devices on a base body. Since the display device is modularized by burying a light emitting device finely formed in an insulating material, to re-shape the light emitting device into a size easy to handle, it is possible to suppress the production cost of the display unit using such display devices, and to ensure a desirable handling performance of the light emitting device; for example, facilitate the carrying of the light emitting device or the mounting thereof on a base body.
    Type: Application
    Filed: May 15, 2002
    Publication date: November 21, 2002
    Inventors: Toyoharu Oohata, Hideharu Nakajima, Yoshiyuki Yanagisawa, Toshiaki Iwafuchi
  • Publication number: 20020153832
    Abstract: A device transfer method includes the steps of: covering a plurality of devices, which have been formed on a substrate, with a resin layer; forming electrodes in the resin layer in such a manner that the electrodes are connected to the devices; cutting the resin layer, to obtain resin buried devices each containing at least one of the devices; and peeling the resin buried devices from the substrate and transferring them to a device transfer body. This device transfer method is advantageous in easily, smoothly separating devices from each other, and facilitating handling of the devices in a transfer step and ensuring good electric connection between the devices and external wiring, even if the devices are fine devices.
    Type: Application
    Filed: January 30, 2002
    Publication date: October 24, 2002
    Inventors: Yoshiyuki Yanagisawa, Toyoharu Oohata, Toshiaki Iwafuchi
  • Publication number: 20020115265
    Abstract: The interface between a first substrate and light-emitting diodes formed on the first substrate is selectively irradiated with an energy beam and transmits the energy beam through the first substrate, thereby selectively releasing the light-emitting diodes. The light-emitting diodes are then transferred onto a device holding layer included on a device holding substrate. Subsequently, the light-emitting diodes are transferred onto a second substrate. The irradiation of the interface with the energy beam enables the devices to be easily released from the first substrate.
    Type: Application
    Filed: December 14, 2001
    Publication date: August 22, 2002
    Inventors: Toshiaki Iwafuchi, Yoshiyuki Yanagisawa, Toyoharu Oohata
  • Patent number: 6425516
    Abstract: A semiconductor device comprising a semiconductor substrate on which metal bumps having narrowed base portions are bonded and coated on its top surface with a resin covering the base portions of the metal bumps, improving reliability of the bump bonds. Also, a method of production of a semiconductor device including steps of forming metal bumps in a wafer state, coating a resin for protecting a wiring surface of a semiconductor chip in the wafer state and cutting the semiconductor chip from the wafer, wherein the metal bumps have narrowed base portions and are bonded to the wiring surface of the semiconductor chip and the resin is coated covering the base portions of the metal bumps.
    Type: Grant
    Filed: April 27, 2000
    Date of Patent: July 30, 2002
    Assignee: Sony Corporation
    Inventors: Satoshi Iwatsu, Toshiaki Iwafuchi, Takashi Saito
  • Publication number: 20020096994
    Abstract: An image display unit and a method of producing the image display unit, wherein the image display unit includes an array of a plurality of light emitting devices for displaying an image, and wherein the method of producing the image display unit employs, for example, a space expanding transfer, whereby a first transfer step includes transferring the devices arrayed on a first substrate to a temporary holding member such that the devices are spaced from each other with a pitch larger than a pitch of the devices arrayed on the first substrate, a second holding step includes holding the devices on the temporary holding member, and a third transfer step includes transferring the devices held on the temporary holding member onto a second board such that the devices are spaced from each other with a pitch larger than the pitch of the devices held on the temporary holding member.
    Type: Application
    Filed: January 30, 2002
    Publication date: July 25, 2002
    Inventors: Toshiaki Iwafuchi, Toyoharu Oohata, Masato Doi
  • Patent number: 6247640
    Abstract: A device for arranging conductive particles in a preselected pattern for the connection of electric circuit boards or electric parts is disclosed. Particularly, a device capable of surely and efficiently transferring, e.g., solder bumps to the electrode pads of a semiconductor chip or the leads of a TAB (Tape Automated Bonding) tape and a conductive particle transferring method using the same are disclosed.
    Type: Grant
    Filed: January 12, 2000
    Date of Patent: June 19, 2001
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kuwazaki, Kazushi Iwata, Yoshihiro Yoshida, Tsutomu Sakatsu, Toshiaki Iwafuchi
  • Patent number: 6063701
    Abstract: A process for manufacturing a device for arranging conductive particles in a preselected pattern for the connection of electric circuit boards or electric parts is disclosed. Particularly, a device capable of surely and efficiently transferring, e.g., solder bumps to the electrode pads of a semiconductor chip or the leads of a TAB (Tape Automated Bonding) tape and a conductive particle transferring method using the same are disclosed.
    Type: Grant
    Filed: September 15, 1997
    Date of Patent: May 16, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Kuwazaki, Kazushi Iwata, Yoshihiro Yoshida, Tsutomu Sakatsu, Toshiaki Iwafuchi