Energy saving in line patterning using pulse laser by reducing overlapping rate with rectangular beam shape

• Published in: International journal of precision engineering and manufacturing 2013-06, Vol.14 (6), p.985-988
• Main Authors: Lee, Jae-Hoon, Lee, Won-Jin, Shin, Dong-Jae, Daavasuren, Gaasuren, Chun, Doo-Man
• Format: Article
• Language: English
• Subjects: Engineering; Industrial and Production Engineering; Materials Science
• ISSN: 2234-7593; 2005-4602
• DOI: 10.1007/s12541-013-0130-y

Line patterning using a pulse laser is important process for fabrication of solar cells, circuit patterning of transparent conductive oxide (TCO) layer and so on. The typical laser beam shape is circular, so high overlapping rate for line patterning is required for making a straight scribed line edge. In this research, the rectangular beam was used to minimize the overlapping rate. The rectangular beam was made by locating a rectangular shape mask between laser source and objective lens. The nanosecond ultra-violet (UV) pulse laser with 355 nm wavelength was used. Indium tin oxide (ITO) coated polyethylene terephthalate (PET) was used for thin conductive layer scribing. The fabricated line patterns with the original circular beam and the rectangular beam were compared under the same process parameters such as laser power, laser pulse frequency, and so on. The overlapping rate was controlled by scan speed. The shape of patterning lines, and the quality of scribed line edge were observed. The rectangular beam could decrease the overlapping rate for straight scribed line edge. Even though the rectangular beam shape had energy loss by blocking the laser beam, it could increase overall energy efficiency of laser patterning by reducing the overlapping rate.