Tokyo, Japan

Yasushi Ishii

This inventor holds 56 USPTO granted patents and 3 published patent applications, primarily in Semiconductor Devices (CPC class H01L). Top assignees: Renesas Electronics Corporation, Renesas Technology Corp., Other. Active years: 1991-2021.

USPTO Granted Patents = 56 

% Patents Active = 92.9

Average Co-Inventor Count = 3.7

ph-index = 9

Forward Citations = 294(Granted Patents)

Forward Citations (Not Self Cited) = 251(Dec 10, 2025)


Inventors with similar research interests:


Location History:

  • Setagaya-ku, Tokyo, JP (1991)
  • Mito, JP (2006 - 2013)
  • Kanagawa, JP (2013 - 2016)
  • Tokyo, JP (1998 - 2021)

Company Filing History:


Years Active: 1991-2021

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Areas of Expertise:
Semiconductor Device
Non-Volatile Memory
Capacitive Element
Manufacturing Method
Gate Electrodes
Memory Cell Group
Split Gate Type
Field Effect Transistors
Wafer Technology
3D Semiconductor
Thermal Management
Memory Fabrication
56 patents (USPTO):Explore Patents

Title: The Innovative Mind of Yasushi Ishii

Introduction: Yasushi Ishii, a prominent inventor based in Tokyo, Japan, has made significant contributions to the field of semiconductor technology. With a remarkable portfolio of 56 patents, his work has played a vital role in advancing memory storage solutions that are essential for modern computing.

Latest Patents: Among his latest innovations is a groundbreaking semiconductor device aimed at enhancing memory efficiency. This semiconductor memory array features a first nonvolatile memory cell that consists of a first charge storage layer and a first gate electrode. Adjacent to this cell is a second nonvolatile memory cell, which also comprises a charge storage layer and a gate electrode. Notably, the configuration allows the first and second electrodes to extend in a direction that is perpendicular to the arrangement of the memory cells. This innovative design ensures that the first electrode's contact section and the second electrode's contact section are electrically separated while providing advanced functionalities in semiconductor memories.

Career Highlights: Yasushi Ishii has worked with esteemed organizations like Renesas Electronics Corporation and Renesas Technology Corporation, where he has driven numerous advancements in semiconductor technology. His extensive experience has earned him recognition as a leader in innovation within the sector.

Collaborations: Throughout his career, Yasushi has collaborated with notable colleagues, including Toshikazu Matsui and Yoshiyuki Kawashima. Their teamwork has contributed to several innovative projects that push the boundaries of memory technology.

Conclusion: Yasushi Ishii stands out as a key figure in the field of semiconductor inventions, with a legacy marked by his impressive patent portfolio and collaborative efforts in the industry. His contributions continue to shape the future of memory technology, solidifying his status as a pioneering inventor.

Profile summary based on public USPTO records.
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