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:
Nov. 21, 1995
Filed:
Mar. 28, 1994
Applicant:
Inventor:
Seiji Samukawa, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H05H / ;
U.S. Cl.
CPC ...
216 69 ; 156345 ; 20429837 ; 20429838 ;
Abstract
A plasma-etching method and an apparatus therefor are provided, in which microwaves are introduced and a high frequency electric fields generated thereby is pulse-modulated by a signal of a frequency higher than about 10 kHz for producing the plasmas for etching a wafer. The pulse modulation of the high frequency electric fields may be performed with a pulse interval time shorter than about 10 .mu.s. The radical production ratio in ECR plasmas, ion temperature and charge accumulation can be controlled thereby enabling the etching performance at a high precision.