陰極スパッター極板の超音波検査法

Japanese Patent JP3803382

B2

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