Company Filing History:
Years Active: 1988
Title: Innovations of Donald J McCarthy
Introduction
Donald J McCarthy is a notable inventor based in Hayward, CA (US). He has made significant contributions to the field of measurement systems, particularly in electron beam lithography. His innovative work has led to the development of a unique patent that enhances the precision of height sensing in various applications.
Latest Patents
One of McCarthy's key patents is the "Specimen distance measuring system." This system utilizes a plate to obstruct the flux of backscattered electrons produced by an electron beam, casting a shadow across a measurement detector that is sensitive to the position of the shadow. The alignment of the shadow plate and measurement detector at an angle of approximately 45 degrees with a substrate allows for effective calibration of the distance measuring system. This invention is particularly useful as a height sensor in electron beam lithography apparatus for sensing the height of a substrate. The system may also include a reference detector positioned to receive backscattered electron flux without obstruction, allowing for compensation of signals obtained by the measurement detector. This feature enables the height sensor to operate independently of variations in electron beam current and substrate backscatter coefficient. Active feedback from the height sensor to a vertical stage actuator facilitates adjustments to the substrate height.
Career Highlights
Donald J McCarthy is associated with The Perkin-Elmer Corporation, where he has contributed to advancements in measurement technologies. His work has been instrumental in enhancing the capabilities of electron beam lithography systems, which are critical in various high-precision manufacturing processes.
Collaborations
Throughout his career, McCarthy has collaborated with notable colleagues such as William A Eckes and Lee H Veneklasen. These collaborations have fostered innovation and have led to the development of advanced technologies in the field.
Conclusion
Donald J McCarthy's contributions to the field of measurement systems, particularly through his patent on the specimen distance measuring system, highlight his innovative spirit and dedication to advancing technology. His work continues to influence the precision of electron beam lithography and related applications.