Toshihide Ujihara

Title: Innovations of Toshihide Ujihara

Introduction

Toshihide Ujihara is a notable inventor based in Hitachi, Japan. He has made significant contributions to the field of semiconductor technology, particularly in the development of gate turn-off thyristors. With a total of 2 patents, Ujihara's work has had a considerable impact on the industry.

Latest Patents

One of Ujihara's latest patents is a gate turn-off (GTO) thyristor of multi-emitter type. This innovative device consists of a plurality of unit GTO thyristors arranged in a strip-like configuration within the same semiconductor substrate. Each unit GTO thyristor is constructed with an N emitter layer, P base layer, N base layer, and P emitter layer. Notably, the P base and N base layers are shared among all unit GTO thyristors, which are formed in a multi-ring configuration. Furthermore, the exposed area of the P emitter layer of a unit GTO thyristor located far from the gate signal input area is designed to be smaller than that of a unit GTO thyristor positioned closer to the gate signal input area.

Career Highlights

Ujihara is currently employed at Hitachi, Ltd., where he continues to advance his research and development efforts. His work has been instrumental in enhancing the performance and efficiency of semiconductor devices.

Collaborations

Ujihara has collaborated with several esteemed colleagues, including Shuroku Sakurada and Tadashi Sakaue. Their combined expertise has contributed to the successful development of innovative technologies in the semiconductor field.

Conclusion

Toshihide Ujihara's contributions to semiconductor technology, particularly through his patents on gate turn-off thyristors, highlight his role as a significant inventor in the industry. His ongoing work at Hitachi, Ltd. continues to influence advancements in this critical area of technology.