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:
Mar. 30, 1999
Filed:
Dec. 09, 1996
Michel Leroy, Saint-Egreve, FR;
Jean Muller, Voiron, FR;
Aluminium Pechiney, Lyons Cedex, FR;
Abstract
A process is provided for ultrasonic testing the internal soundness of cathode sputtering targets including an active part made of very pure aluminum or of very pure aluminum alloy. In particular, this process, after the choice of an ultrasound sensor functioning at an operating frequency greater than 5 MHZ, and preferably between 10 and 50 MHZ, and adjustment of the appropriate measurement sequence, using a target immersed in a liquid and having certain artificial defects simulating the decohesions in the target, consists of taking a count in terms of size and number of the internal decohesions per unit volume and of selecting the targets with a decohesion density of .ltoreq.0.1 decohesion larger than 0.1 mm per cm.sup.3 of active metal of the targets, and preferably less than 0.1 decohesion larger than 0.04 mm per cm.sup.3 of active metal. The process also pertains to selecting precursors of the cathode sputtering targets, containing less than 0.1 internal decohesion larger than 0.04 mm per cm.sup.3.