Mitsumasa Koyanagi

Title: Mitsumasa Koyanagi: Innovator in Semiconductor Memory Technology

Introduction

Mitsumasa Koyanagi is a prominent inventor based in Cupertino, CA (US). He has made significant contributions to the field of semiconductor memory technology, holding a total of 5 patents. His work has been instrumental in advancing the capabilities and efficiency of memory devices.

Latest Patents

Koyanagi's latest patents focus on semiconductor memory systems. One of his notable inventions describes a semiconductor memory that comprises a capacitor with a data storage portion and an insulated-gate field-effect transistor. The capacitor is formed by a plate made up of the side walls and base of a groove in a semiconductor substrate. A capacitor electrode is formed on the side walls and base, over an insulation film, and is electrically connected to the source or drain of the insulated-gate field-effect transistor. Various embodiments are provided to reduce size and prevent leakage between memory cells. These include forming stacked capacitors, placing the transistor over the capacitor, utilizing a silicon-over-insulator arrangement for the transistor, forming a common capacitor plate, and incorporating high impurity layers within the substrate.

Career Highlights

Mitsumasa Koyanagi has had a distinguished career at Hitachi, Ltd., where he has contributed to various innovative projects in semiconductor technology. His expertise in memory systems has positioned him as a key figure in the industry.

Collaborations

Koyanagi has worked alongside notable colleagues such as Yoshio Sakai and Hideo Sunami. Their collaborative efforts have further advanced the research and development of semiconductor technologies.

Conclusion

Mitsumasa Koyanagi's contributions to semiconductor memory technology have had a lasting impact on the field. His innovative patents and collaborative work continue to influence advancements in memory systems.