Abstract
Laser machining of multi-layer thin film is promissing to become an important processing in fabrications of electronic circuits. The various factors having influence on the characteristics of multi-layer thin film machining with a laser are evaluated theoretically and experimentally. The three dimensional heat diffusion equations including laser light absorption in multi-layer thin film structure are solved numerically to give the time evolution of temperature. Experiments were performed on amorphous Si (a-Si) multi-layer thin film structure of various thickness on transparent conductive oxide(TCO)/glass substrate to verify numerical results. The samples were irradiated with a Q-switched Nd : YAG laser at λ= 1. 06 μm and at λ =0.53, μm. The experimental results on the dependence of laser wavelength, laser pulse duration and laser irradiated energy on machining characteristics are in good agreement with the calculated results.
