Title :
Photoacoustic detection of microcracks of thin film head alumina using Nd:YAG laser irradiation
Author :
Chekanov, A. ; Hong, M.H. ; Low, T.S. ; Lu, Y.F.
Author_Institution :
Data Storage Inst., Nat. Univ. of Singapore, Singapore
fDate :
9/1/1997 12:00:00 AM
Abstract :
Acoustic wave generation during Nd:YAG laser irradiation on thin film head alumina is studied. It is found that with proper selection of laser parameters, the acoustic waveforms observed are completely different for pristine head and head with preexisting microcracks. It has potential applications of thin-film heads and head wafers
Keywords :
alumina; crack detection; magnetic heads; magnetic thin film devices; microcracks; photoacoustic effect; Al2O3; Nd:YAG laser irradiation; acoustic wave generation; alumina; microcracks; photoacoustic detection; thin film head; Acoustic beams; Acoustic signal detection; Acoustic testing; Acoustic waves; Laser beams; Lenses; Magnetic heads; Microphones; Nondestructive testing; Transistors;
Journal_Title :
Magnetics, IEEE Transactions on
