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:
Apr. 20, 2004
Filed:
Sep. 13, 2000
Tomoko Wake, Tokyo, JP;
NEC Electronics Corporation, Kanagawa, JP;
Abstract
An objective of this invention is to provide a process for selecting rationally and quickly a wet process treatment in which an etchant can be shared based on a minimum preliminary investigation while eliminating cross contamination derived from a newly employed material, in a cleaning-apparatus line configuration in a process for manufacturing a silicon semiconductor device. In advance, an element which is suspected to cause cross contamination is added to an etchant used in a wet processing, a silicon substrate is immersed in the etchant, and then a correlation between a concentration of the element adhesively remaining still on the surface of the silicon substrate after the etchant is washed out with water and a concentration of the dissolved element in the etchant. On the basis of the result, the upper concentration limit of the element remaining by cross contamination is estimated when sharing the etchant. Then, with reference to the upper limit, whether deterioration of device properties occurs is evaluated to determine acceptability of etchant sharing.