The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 09, 1994
Filed:
Feb. 25, 1993
Hisashi Goda, Tokyo, JP;
Yasutoshi Asahina, Tokyo, JP;
Masayuki Hashimoto, Tateyama, JP;
Naoki Oka, Tateyama, JP;
Abstract
A method of etching a polysilicon film specimen by an electronic cyclotron resonance etching technique or a microwave plasma etching technique includes the first process in which a mixed gas containing Cl.sub.2 and HBr is used as a process gas for etching, the Cl.sub.2 occupying 50-70 vol. % of the whole mixed gas; and the second process in which a mixed gas containing HBr and He is used, with HBr being in a proportion of 20-50 vol. % of the mixed gas, and a low bias voltage from -100 to -30 volts is applied to a specimen carrier. Further, in the first and second processes, a mixed gas containing HBr and He is used, with HBr being in a proportion of 20-50 vol. %, and a relatively high bias voltage from -250 to -100 volts is applied to the specimen carrier in the first process, while a low bias voltage from -100 to -30 volts is applied to the same in the second process. According to the present invention, a polysilicon film can be etched without causing undercut and with high dimensional accuracy.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile