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:
Jun. 06, 2000
Filed:
Jun. 05, 1997
Jung-ho Kang, Kyounggi-do, KR;
Kwang-yul Lee, Kyounggi-do, KR;
Dong-cho Maeng, Kyounggi-do, KR;
Jong-sub Hwang, Kyunggi-do, KR;
Samsung Electronics Co., Ltd., Suwon, KR;
Abstract
A chemical bath of an overflow-type includes an inner bath which includes a plurality of holes on its sidewalls. The holes are formed in such a manner that they are spaced apart from the upper end of the inner bath at a predetermined distance. In this chemical bath, the chemical in the inner bath flows over the upper end of the inner bath into the outer bath and is simultaneously is discharged to the outer bath through the holes. Accordingly, unless either of the opposed sidewalls slopes lower than another by over a predetermined value, the chemical can flow continuously at nearly the same rate at both sidewalls of the inner bath. This reduces the difference of the etching rate between the respective wafers caused by the difference of the position of the wafers immersed in the chemical in the inner bath and leads to an improvement in the reliability of the etching process.