Processing of metals by double pulses with short laser pulses

Experimental results related to the influence of time delayed pulses for ablation efficiency with short multi pulses (pulse duration of 5 ps) are reported. A significant improvement of the micro structuring quality at relatively high fluence regime in metals is obtained. Less removed or recast matter is observed and the processed surface appears to be smoother with better roughness. Ablation depths and burr heights are compared for single pulses and double pulses in steel, Al and Cu as a function of scans number. Best results are obtained for weak time delays, typically less than 1 ps.

[1]  Friedrich Dausinger,et al.  High precision deep drilling with ultrashort pulses , 2003, International Symposium on Laser Precision Microfabrication.

[2]  Brunel,et al.  Thermal response of metals to ultrashort-pulse laser excitation. , 1988, Physical review letters.

[3]  Boris N. Chichkov,et al.  Ablation of metals by ultrashort laser pulses , 1997 .

[4]  V. Couderc,et al.  4-W and 23-ps pulses from a lamp-pumped Nd:YAG laser passively mode-locked by polarization switching in a KTP crystal , 1999 .

[5]  Friedrich Dausinger,et al.  Surface structuring of metals with short and ultrashort laser pulses , 2003, International Symposium on Laser Precision Microfabrication.

[6]  A. Tünnermann,et al.  Femtosecond, picosecond and nanosecond laser ablation of solids , 1996 .

[7]  H. Sawada,et al.  Development of dicing technique for thin semiconductor substrate using temporally shaped femtosecond laser , 2004 .

[8]  Razvan Stoian,et al.  Laser ablation of dielectrics with temporally shaped femtosecond pulses , 2002 .

[9]  E. Mazur,et al.  Micromachining bulk glass by use of femtosecond laser pulses with nanojoule energy. , 2001, Optics letters.

[10]  M. D. Shirk,et al.  A review of ultrashort pulsed laser ablation of materials , 1998 .

[11]  J. López,et al.  High-aspect-ratio microdrilling in polymeric materials with intense KrF laser radiation , 1999 .

[12]  J. Güdde,et al.  The role of electron–phonon coupling in femtosecond laser damage of metals , 1999 .

[13]  Schmidt,et al.  Dynamics of laser desorption and ablation of metals at the threshold on the femtosecond time scale , 2000, Physical review letters.

[14]  C. Donnet,et al.  New methods to control quality and precision of micro-machining with femtosecond lasers , 2003, International Symposium on Laser Precision Microfabrication.

[15]  A. Semerok,et al.  Ultrashort double pulse laser ablation of metals , 2004 .

[16]  Friedrich Dausinger,et al.  Femtosecond technology for precision manufacturing: fundamental and technical aspects , 2003 .

[17]  P. Corkum,et al.  Influence of laser parameters and material properties on micro drilling with femtosecond laser pulses , 1999 .

[18]  C. Donnet,et al.  Ablation comparison with low and high energy densities for Cu and Al with ultra-short laser pulses , 2005 .

[19]  Andreas Ruf,et al.  Plasma effects during ablation and drilling using pulsed solid-state lasers , 2003, Other Conferences.

[20]  Mohamed Chaker,et al.  Ablation of aluminum thin films by ultrashort laser pulses , 2001 .

[21]  Andreas Ruf,et al.  Fundamental aspects in machining of metals with short and ultrashort laser pulses , 2004, SPIE LASE.

[22]  Razvan Stoian,et al.  Temporal pulse manipulation and ion generation in ultrafast laser ablation of silicon , 2003 .

[23]  Klaus Sokolowski-Tinten,et al.  Transient States of Matter during Short Pulse Laser Ablation , 1998 .

[24]  Boris N. Chichkov,et al.  Short-pulse laser ablation of solid targets , 1996 .

[25]  Robin S. Marjoribanks,et al.  Ultra high repetition rate (133 MHz) laser ablation of aluminum with 1.2-ps pulses , 1999 .

[26]  Norris,et al.  Time-resolved observation of electron-phonon relaxation in copper. , 1987, Physical review letters.

[27]  X Zhu,et al.  A new method for determining critical pulse width in laser material processing , 2000 .