Cathode sputtering targets selected by ultrasonic inspection for their low level of particle emission
US5955673A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 12, 1996 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Apr 12, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2697
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A process using ultrasonic inspection for testing the internal soundness of cathode sputtering targets, whose active part is made of aluminum with a very high degree of purity or a very pure aluminum alloy, consisting, after selection of an ultrasound sensor functioning at an operating frequency greater than 5 MHz, preferably between 10 and 50 MHz, and adjusting the appropriate measurement sequence, using a target immersed in a liquid and which has ceratin artificial defects simulating decohesions in the target, taking a count in terms of size and number of the internal decohesions per unit volume and selecting, for the applications requiring a very high degree of etching fineness, the targets with a decohesion density of .ltoreq.0.1 decohesion larger than 0.1 mm/cm.sup.3 of active metal of the target, and cathode sputtering targets selected according to the process having no more than 0.1 internal decohesion larger than 0.1 mm/cm.sup.3 of active metal of the target.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.