Company Filing History:
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Title: Naoto Yonemaru: Innovator in Photomask Technology
Introduction
Naoto Yonemaru is a notable inventor based in Tokyo, Japan. He has made significant contributions to the field of photomask technology, particularly through his innovative patent. His work has implications for the semiconductor industry, where precision and quality are paramount.
Latest Patents
Yonemaru holds a patent for a "Mask blank and method of manufacturing photomask." This invention features a mask blank structure where a thin film for pattern formation and a hard mask film are stacked on a transparent substrate. The thin film is composed of a material containing chromium, while the hard mask film consists of a lower layer made from silicon and oxygen, and an upper layer made from tantalum and oxygen, with an oxygen content of 30 atom % or more. Notably, the thickness ratio of the upper layer to the total thickness of the hard mask film is 0.7 or less.
Career Highlights
Throughout his career, Naoto Yonemaru has worked with prominent companies in the industry. He has been associated with Hoya Corporation and Tekscend Photomask Corporation, where he has contributed to advancements in photomask manufacturing processes.
Collaborations
Yonemaru has collaborated with notable colleagues, including Hitoshi Maeda and Kazutake Taniguchi. Their combined expertise has likely enhanced the development of innovative solutions in the field.
Conclusion
Naoto Yonemaru's contributions to photomask technology through his patent and collaborations highlight his role as an influential inventor in the industry. His work continues to impact the semiconductor field significantly.