Patents by Inventor Naokatsu Ikegami

Naokatsu Ikegami 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: 20230210012
    Abstract: A piezoelectric device includes a base member, a first conductive film arranged above the base member in contact with an upper surface of the base member, a piezoelectric film arranged above the first conductive film in contact with an upper surface of the first conductive film, a second conductive film arranged on the piezoelectric film, and an insulating portion provided inside a trench penetrating through the piezoelectric film and the first conductive film. The insulating portion has a higher electrical resistivity than the piezoelectric film.
    Type: Application
    Filed: October 25, 2022
    Publication date: June 29, 2023
    Inventors: YUYA SAKURAI, HIDEO YAMADA, MEGUMI SUZUKI, TETSUYA ENOMOTO, AKIHIKO TESHIGAHARA, TAKAHIDE USUI, NAOKATSU IKEGAMI, SHUJI KATAKAMI
  • Publication number: 20230210010
    Abstract: A piezoelectric device includes a support member, and a vibrating portion provided on a support surface of the support member. The vibrating portion includes, in addition to a first electrode, a piezoelectric film and a second electrode arranged in a stacking direction, an insulating film configured to increase an electric resistance value between the first and second electrodes. The first electrode is provided on the support surface of the support member, and includes an opening penetrating the first electrode in the stacking direction. The piezoelectric film is provided on the first electrode to extend across the opening. The second electrode is provided on the piezoelectric film. The insulating film is provided at a position between the first electrode and the second electrode, and at least a part of the insulating film overlaps with the opening in the stacking direction.
    Type: Application
    Filed: October 25, 2022
    Publication date: June 29, 2023
    Inventors: Tetsuya ENOMOTO, Takahide USUI, Naokatsu IKEGAMI, Shuji KATAKAMI
  • Patent number: 7622394
    Abstract: The method of fabricating a semiconductor device includes subjecting a semiconductor substrate to trench etching by alternately repeating an etching step and a deposition step. The etching step creates a trench structure by dry-etching the exposed surface of the semiconductor substrate. An etching mask is formed on the surface of the semiconductor substrate so that the semiconductor substrate has the exposed portion. The deposition step deposits a protection film for suppressing etching of the trench side walls. The method of fabricating a semiconductor device also includes subjecting the semiconductor substrate that has just undergone the trench etching to a heat treatment at a predetermined temperature. The semiconductor substrate is heat-treated within a temperature range of 300 to 500° C. immediately following the trench etching, for example. Plasma ashing is then performed.
    Type: Grant
    Filed: March 29, 2006
    Date of Patent: November 24, 2009
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Naokatsu Ikegami
  • Patent number: 7509858
    Abstract: An acceleration sensor has a mass movably linked to a peripheral attachment section to which at least one stopper is attached to stop the motion of the mass in a certain direction. In the absence of acceleration, the mass rests at a distance from a first surface of the stopper. A quantity of a curable elastic adhesive on a second surface of the stopper absorbs impact of the mass on the first surface, enabling the acceleration sensor to survive mechanical shock. The curable elastic adhesive may adhere to the cover of a package in which the acceleration sensor is enclosed. The curable elastic adhesive may be applied as a drop or swath from a dispenser, which simplifies the manufacturing process and reduces the manufacturing cost.
    Type: Grant
    Filed: December 2, 2005
    Date of Patent: March 31, 2009
    Assignee: OKI Semiconductor Co., Ltd.
    Inventor: Naokatsu Ikegami
  • Patent number: 7323354
    Abstract: The present invention provides a method of manufacturing MEMS devices, comprising the steps of forming MEMS device bodies in a first substrate, defining concave portions around the MEMS device bodies over the first substrate, forming convex portions coincident with the concave portions in a second substrate, fitting the convex portions in the concave portions, respectively, to join the first substrate and the second substrate to each other, thereby forming a third substrate, sticking the third substrate to a UV sheet on the second substrate side, and dicing the third substrate to separate the MEMS device bodies from one another.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: January 29, 2008
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Naokatsu Ikegami
  • Publication number: 20070215966
    Abstract: A piezoresistance element formed in a semiconductor substrate, includes a pair of contact regions formed in the semiconductor substrate; a groove formed between the pair of contact regions; a resistance layer formed in the groove, the resistance layer having a conductive type opposing to the semiconductor substrate; and a silicon layer formed on the resistance layer, the silicon layer having a conductive type corresponding to the semiconductor substrate.
    Type: Application
    Filed: January 4, 2007
    Publication date: September 20, 2007
    Applicant: OKI ELECTRIC INDUSTRY CO., LTD
    Inventor: Naokatsu Ikegami
  • Patent number: 7153716
    Abstract: Micro-electrical-mechanical systems are fabricated in a substrate having a sacrificial layer sandwiched between two semiconductor layers. The semiconductor layers are selectively etched to create non-etched frames and etched microstructures immobilized within the frames by the sacrificial layer. An adhesive sheet is attached to one surface of the substrate, and the substrate is diced into chips, each including one frame and one immobilized microstructure. The sacrificial layer is then selectively etched to free a movable member in each microstructure. Finally, the chips are detached from the adhesive sheet, each chip becoming a micro-electrical-mechanical system. This fabrication method provides a simple and inexpensive way to avoid damage to the microstructure during the dicing process.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: December 26, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Naokatsu Ikegami
  • Publication number: 20060223324
    Abstract: The method of fabricating a semiconductor device includes subjecting a semiconductor substrate to trench etching by alternately repeating an etching step and a deposition step. The etching step creates a trench structure by dry-etching the exposed surface of the semiconductor substrate. An etching mask is formed on the surface of the semiconductor substrate so that the semiconductor substrate has the exposed portion. The deposition step deposits a protection film for suppressing etching of the trench side walls. The method of fabricating a semiconductor device also includes subjecting the semiconductor substrate that has just undergone the trench etching to a heat treatment at a predetermined temperature. The semiconductor substrate is heat-treated within a temperature range of 300 to 500° C. immediately following the trench etching, for example. Plasma ashing is then performed.
    Type: Application
    Filed: March 29, 2006
    Publication date: October 5, 2006
    Inventor: Naokatsu Ikegami
  • Patent number: 7100448
    Abstract: An accelerometer includes: a sensor chip including a weight portion for detecting a force imparted from outside, a frame portion that surrounds the weight portion, a beam portion that is deflectable and flexibly supports the weight portion, and a sensor element whose electric resistance varies depending on an amount by which the beam portion deflects; and a spacer provided at a position on a surface of a mounting substrate which position corresponds to the central portion of the weight portion. The sensor chip is mounted on the mounting substrate with a bottom surface of the frame portion being fixed at a predetermined position on the mounting substrate by an adhesive portion. The spacer has a thickness greater than that of the adhesive portion and may be formed by an adhesive concurrently with the adhesive portion, with a gap being maintained between the bottom surface of the weight portion and the spacer.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: September 5, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Naokatsu Ikegami
  • Patent number: 7084069
    Abstract: Abstract of the Disclosure A method for manufacturing a semiconductor device including a conductive path extending from the upper surface of an insulating layer on a semiconductor substrate to a conductive member embedded in the insulating layer. An etching mask, which defines an etched hole for the conductor path, is formed on the insulating layer within a specified permissible error, and that portion of the insulating layer which is not covered by the etching mask is removed by a reactive ion etching unit having a reaction chamber into which a reactive gas of CHF3/CO is introduced at a CHF3/CO flow ratio of about 15/85. After this, the etched hole formed by an etching process is filled with a conductive material for the conductive path.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: August 1, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Naokatsu Ikegami
  • Publication number: 20060130580
    Abstract: An acceleration sensor has a mass movably linked to a peripheral attachment section to which at least one stopper is attached to stop the motion of the mass in a certain direction. In the absence of acceleration, the mass rests at a distance from a first surface of the stopper. A quantity of a curable elastic adhesive on a second surface of the stopper absorbs impact of the mass on the first surface, enabling the acceleration sensor to survive mechanical shock. The curable elastic adhesive may adhere to the cover of a package in which the acceleration sensor is enclosed. The curable elastic adhesive may be applied as a drop or swath from a dispenser, which simplifies the manufacturing process and reduces the manufacturing cost.
    Type: Application
    Filed: December 2, 2005
    Publication date: June 22, 2006
    Inventor: Naokatsu Ikegami
  • Patent number: 7029957
    Abstract: A method of manufacturing a semiconductor device includes the steps of, (1) preparing an SOI substrate, (2) forming a metal layer on the SOI substrate, (3) performing a first anneal treatment to the metal layer at a relatively low temperature in order to transform the metal layer to a first silicide layer, (4) forming an insulating layer on the first silicide layer, and (5) forming a contact hole, which reaches the first silicide layer, in the insulating layer; and (6) performing a second anneal treatment to the silicide layer at a relatively high temperature in order to transform the first silicide layer to a second silicide layer.
    Type: Grant
    Filed: July 24, 2003
    Date of Patent: April 18, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Naokatsu Ikegami
  • Patent number: 7004030
    Abstract: An acceleration sensor capable of standing a great acceleration is to be provided. It is configured of a mounting board and a sensor chip in which the sensor chip is formed of a weight, a beam and a frame. Then, the weight is surrounded by the frame. The weight is joined to the frame by a plurality of the beams, and the weight is separated from the board by being supported by the beams. Additionally, a thin, rectangular stopper is disposed on the mounting board right under the weight.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: February 28, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Naokatsu Ikegami, Takasumi Kobayashi
  • Publication number: 20050266599
    Abstract: Micro-electrical-mechanical systems are fabricated in a substrate having a sacrificial layer sandwiched between two semiconductor layers. The semiconductor layers are selectively etched to create non-etched frames and etched microstructures immobilized within the frames by the sacrificial layer. An adhesive sheet is attached to one surface of the substrate, and the substrate is diced into chips, each including one frame and one immobilized microstructure. The sacrificial layer is then selectively etched to free a movable member in each microstructure. Finally, the chips are detached from the adhesive sheet, each chip becoming a micro-electrical-mechanical system. This fabrication method provides a simple and inexpensive way to avoid damage to the microstructure during the dicing process.
    Type: Application
    Filed: February 25, 2005
    Publication date: December 1, 2005
    Inventor: Naokatsu Ikegami
  • Publication number: 20050236682
    Abstract: The present invention provides a method of manufacturing MEMS devices, comprising the steps of forming MEMS device bodies in a first substrate, defining concave portions around the MEMS device bodies over the first substrate, forming convex portions coincident with the concave portions in a second substrate, fitting the convex portions in the concave portions, respectively, to join the first substrate and the second substrate to each other, thereby forming a third substrate, sticking the third substrate to a UV sheet on the second substrate side, and dicing the third substrate to separate the MEMS device bodies from one another.
    Type: Application
    Filed: November 24, 2004
    Publication date: October 27, 2005
    Inventor: Naokatsu Ikegami
  • Publication number: 20050097958
    Abstract: An accelerometer includes: a sensor chip including a weight portion for detecting a force imparted from outside, a frame portion that surrounds the weight portion, a beam portion that is deflectable and flexibly supports the weight portion, and a sensor element whose electric resistance varies depending on an amount by which the beam portion deflects; and a spacer provided at a position on a surface of a mounting substrate which position corresponds to the central portion of the weight portion. The sensor chip is mounted on the mounting substrate with a bottom surface of the frame portion being fixed at a predetermined position on the mounting substrate by an adhesive portion. The spacer has a thickness greater than that of the adhesive portion and may be formed by an adhesive concurrently with the adhesive portion, with a gap being maintained between the bottom surface of the weight portion and the spacer.
    Type: Application
    Filed: September 22, 2004
    Publication date: May 12, 2005
    Inventor: Naokatsu Ikegami
  • Publication number: 20050097960
    Abstract: An acceleration sensor capable of standing a great acceleration is to be provided. It is configured of a mounting board and a sensor chip in which the sensor chip is formed of a weight, a beam and a frame. Then, the weight is surrounded by the frame. The weight is joined to the frame by a plurality of the beams, and the weight is separated from the board by being supported by the beams. Additionally, a thin, rectangular stopper is disposed on the mounting board right under the weight.
    Type: Application
    Filed: September 26, 2003
    Publication date: May 12, 2005
    Inventors: Naokatsu Ikegami, Takasumi Kobayashi
  • Publication number: 20050019991
    Abstract: A method of manufacturing a semiconductor device includes the steps of, (1) preparing an SOI substrate, (2) forming a metal layer on the SOI substrate, (3) performing a first anneal treatment to the metal layer at a relatively low temperature in order to transform the metal layer to a first silicide layer, (4) forming an insulating layer on the first silicide layer, and (5) forming a contact hole, which reaches the first silicide layer, in the insulating layer; and (6) performing a second anneal treatment to the silicide layer at a relatively high temperature in order to transform the first silicide layer to a second silicide layer.
    Type: Application
    Filed: July 24, 2003
    Publication date: January 27, 2005
    Inventor: Naokatsu Ikegami
  • Publication number: 20040092111
    Abstract: Disclosed herein is a via hole dry etching method using an organic SOG film as an interlayer dielectric having low-K. In the dry etching method, a mixed gas containing at least C4F8 and O2 is used as an etching gas and an O2/(C4F8+O2) mixture ratio is set to 50% or less, thereby to carry out via hole dry etching. Further, the via hole dry etching is carried out by using a mixed gas containing at least CF4, CHF3 and N2 and setting the quantity of flow of N2 to above 10% and below 80% of the quantity of flow of CF4+CHF3+N2.
    Type: Application
    Filed: November 3, 2003
    Publication date: May 13, 2004
    Inventor: Naokatsu Ikegami
  • Patent number: 6624010
    Abstract: A method of manufacturing a semiconductor device includes the steps of, (1) preparing an SOI substrate, (2) forming a metal layer on the SOI substrate, (3) performing a first anneal treatment to the metal layer at a relatively low temperature in order to transform the metal layer to a first silicide layer, (4) forming an insulating layer on the first silicide layer, and (5) forming a contact hole, which reaches the first silicide layer, in the insulating layer; and (6) performing a second anneal treatment to the silicide layer at a relatively high temperature in order to transform the first silicide layer to a second silicide layer.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: September 23, 2003
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Naokatsu Ikegami