Atsushi Yokohata

Title: Innovations by Atsushi Yokohata

Introduction

Atsushi Yokohata is a notable inventor based in Joetsu, Japan. He has made significant contributions to the field of photomask technology, holding a total of 4 patents. His work focuses on methods for defect inspection and manufacturing processes that enhance the quality and efficiency of photomask blanks.

Latest Patents

Yokohata's latest patents include innovative methods for defect inspection, sorting, and manufacturing of photomask blanks. One of his key inventions involves a photomask blank that is inspected for defects by irradiating inspection light onto its surface. The reflected light is collected through an inspection optical system to form a magnified image, allowing for the extraction of feature parameters related to light intensity distribution. This method effectively identifies defects with bump or pit shapes, ensuring high reliability in defect discrimination. Additionally, his defect inspection method enables the production of photomask blanks with no pinhole defects at lower costs and higher yields.

Another significant patent details a method for inspecting defects present on the surface of a photomask blank that includes an optical film and a thin film. This method involves selecting an inspection treatment procedure and a criterion for determining the rugged shape of the defect. By applying inspection light to the defect region and analyzing the reflected light, Yokohata's method allows for precise determination of the defect's rugged shape based on light intensity distribution.

Career Highlights

Yokohata is currently employed at Shin-Etsu Chemical Co., Ltd., where he continues to innovate in the field of photomask technology. His work has contributed to advancements in manufacturing processes that are crucial for the semiconductor industry.

Collaborations

Throughout his career, Atsushi Yokohata has collaborated with esteemed colleagues such as Hiroshi Fukuda and Tsuneo Terasawa. These collaborations have further enriched his research and development efforts in photomask technology.

Conclusion

Atsushi Yokohata's contributions to the field of photomask technology through his innovative patents have significantly impacted the industry. His methods for defect inspection and manufacturing processes continue to enhance the quality and efficiency of photomask blanks.