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:
May. 28, 1991
Filed:
Jun. 09, 1989
Helmut Endl, Freising, DE;
Helmut Rinck, Langenbach, DE;
Abstract
An apparatus for wet etching of thin films with which etching rate differences as between various regions of a respective thin film down to only 5% can be achieved. The apparatus includes a housing (10) providing a liquid treatment chamber in which at least one rotational-symmetrical basket (12; 14) is arranged for accommodating semiconductor slices (16) having the thin films to be etched. The basket (12, 14) rests on two rollers (18, 20; 22), one of which is driven. Longitudinally above the basket (12; 14), flat jet nozzles (24) are arranged in such a manner that the jets of etching solution sprayed out of the nozzles form a homogeneous flat jet (26). The flat jet (26) is directed laterally in the direction of the axis of symmetry of the basket (12; 14). With this apparatus, overflow conditions on the surfaces of the slices (16) to be processed are obtained which are so uniform that the apparatus is suitable for use in the wet etching of aluminium layers in device fabrication.