Location History:
- Ome-shi, Tokyo, JP (2001)
- Ome, JP (2001 - 2004)
- Oume, JP (2003 - 2007)
Company Filing History:
5 out of 42,508 
1 out of 832,880 Years Active: 2001-2007
Title: The Innovations of Tadashi Umezawa
Introduction
Tadashi Umezawa is a notable inventor based in Oume, Japan. He has made significant contributions to the field of semiconductor technology, holding a total of 6 patents. His work focuses on advanced surface processing methods and improvements in dynamic random access memory.
Latest Patents
One of Umezawa's latest patents is a sample surface processing method. This method involves a surface processing technique for a sample with a mask layer that does not contain carbon as a major component. The process includes installing the sample in a vacuum container, generating a plasma from a mixture of halogen gas and adhesive gas, and applying a radio frequency bias voltage. The control of the periodic on-off of the radio frequency bias voltage is also a critical aspect of this innovation.
Another significant patent is related to dynamic random access memory with improved contact arrangements. This invention addresses the prevention of undulations in polycrystal silicon plugs within bit line contact holes. It also avoids the undesired etching of silicide film at the contacts of bit lines and polycrystal silicon plugs. The bit lines are formed from a laminate film that includes titanium, titanium nitride, and tungsten films, enhancing the overall performance of the semiconductor device.
Career Highlights
Throughout his career, Umezawa has worked with prominent companies, including Hitachi, Ltd. His experience in these organizations has contributed to his expertise in semiconductor technology and innovation.
Collaborations
Umezawa has collaborated with notable coworkers such as Takafumi Tokunaga and Motohiko Yoshigai. Their combined efforts have led to advancements in the field of semiconductor technology.
Conclusion
Tadashi Umezawa's contributions to semiconductor technology through his innovative patents and collaborations highlight his importance in the field. His work continues to influence advancements in technology and improve the efficiency of electronic devices.