| 摘要 |
PURPOSE:To perform the laser process of high quality with high yield by a method wherein laser irradiation is applied to a part to be processed and a part of the same structure at a low level impossible to perform the desired process to obtain reflectivity, and the most suitable laser irradiation condition is set up from reflectivity. CONSTITUTION:Laser output 2 is sufficiently lowered, and a wafer 27 is irradiated by luminous energy P0. When reflectivity is indicated by (r), transmissivity of the optical system is by (t), and luminous energy is set as P27=P0.r21.t28. r22.(1-r25).r23.t4, reflected luminous energy becomes to P'27=P26/ r25.r23.t4, and reflectivity of the wafer is expressed by P'27/P27. Output 2 is detected 24, and reflected luminous energy is detected 26 to control 29 transmitted luminous energy 28 and laser output P0. For example, when relative absorption power density is selected to 0.55, irradiation pulses are selected to 50, and transmissivity is set up to t'28=0.55/P.r21.r22.(1-r26).r23.t4, relative power density of 0.55 is always absorbed at a poly-Si wiring part, and the most suitable connection can be attained independently of the variation of reflectivity according to the variation of film thickness. |
