ガウス型熱入力による温度分布
レーザによる薄膜加工の研究(第3報)
1971 年 37 巻 443 号 p. 901-906
詳細
1971 年 37 巻 443 号 p. 901-906
The various factors having influence on the characteristics of thin film machining with a Q-switched laser are evaluated theoretically and experimentally. First, the radial distributions of temperature in thin films are presented in a simplified and generalized form by modifying the solution of the heat flow equation and the effects of the beam parameters and material properties on the machining results are investigated. Next, the practical applicability of the theoretical results is discussed experimentally. The results obtained are as follows :
1) For the area where the distance from the center is within 1.5 times the beam spot size ωf, the temperature distribution can be approximated by a Gaussian one. It is expressed by the simple equation which consists of a temperature spot size ωt defined in the same manner as ωf and a threshold power Po, m required for machining.
2) ωf is in the region of 10 μm - 20 μm, ωt is nearly equal to ωf. When ωf is less than 10 μm, ωt varies with the thermal conductivity of a thin film.
3) The experimental values of Po, m agree qualitatively with the calculated results. With respect to ωt, the difference between the experimental and theoretical values is less than 15%.
