Laser ablation studies of metallic thin films

Aluminium thin films on glass substrates have been ablated by a pulsed Nd:YAG laser (wavelength 532 nm). The behaviour of the ablation process can be measured by a number of possible probe techniques. Several of these are discussed and the advantages and the difficulties pointed out. Optical methods are used to characterize the properties of the film. The transmission of the film was studied as a function of film thickness and theoretical calculations of the film transmission were carried out. A transmission technique has been used to estimate the Laser Induced Damaged Threshold (LIDT) measurement. A piezoelectric microphone was mounted in front of the surface to detect the acoustic signal caused by vaporization of the sample material during the ablation process. Data catter, and inconsistent LIDT data from the transmission technique and acoustic detection method were obtained. SEM pictures of the ablated spot showed that the inconsistent LIDT data was caused by different mechanisms: melt-ejection and vaporization. A plot of LIDT value as a function of film thickness was obtained by selecting consistent LIDT dataSIGLEAvailable from British Library Document Supply Centre-DSC:D206439 / BLDSC - British Library Document Supply CentreGBUnited Kingdo