Product Code: ICAL06_M1003

Improved Picosecond Laser Radiation for Micro-Machining
Authors:
Thomas Herrmann, Lumera Laser GmbH; Kaiserslautern Germany
Achim Nebel, Lumera Laser GmbH; Kaiserslautern Germany
Bernhard Henrich, Lumera Laser GmbH; Kaiserslautern Germany
Hatim Haloui, Lumera Laser GmbH; Kaiserslautern Germany
Ralf Knappe, Lumera Laser *GmbH; Kaiserslautern Germany
Presented at ICALEO 2006

Picosecond laser pulses are used to micro-machine virtually any material with highest precision and minimal thermal impact. Best quality has been demonstrated at low fluence removal with pulse energies of a few µJ. Economical throughput is achieved by very high pulse repetition rates of more than 500kHz. Although picosecond laser systems broke into the industrial market more than a year ago, wide and practical experience of micro-machining with picosecond pulses is limited thus far. In order to achieve outstanding quality in laser micro-machining with picosecond lasers the proper selection of laser parameters is important and the proper process parameters are also critical. For example, in the picosecond pulse regime the removal rates, the quality and the speed in structuring materials show a strong dependence on the laser wavelengths. New generation of ps-lasers comes with efficient and robust harmonic generators. This enables the users to choose the proper wavelength to achieve the best quality in picosecond laser machining of metals, semiconductors and dielectrics. A guideline for picosecond laser machining will be presented. Laser and process parameters like pulse energies, repetition rate, wavelengths, etc., will be discussed for several materials.