Author :
Matulionis, I. ; Nakade, S. ; Compaan, A.D.
Author_Institution :
Dept. of Phys. & Astron., Toledo Univ., OH, USA
Abstract :
We have studied the performance of six different types of laser systems for scribing of the polycrystalline thin-film PV materials: ZnO, SnO2, CdTe, CIGS, Mo, and Si. The laser systems were KrF and XeCl excimer, copper vapor, quasi-cw Nd:YAG (both Q-switched and mode-locked), and flashlamp-pumped Nd:YAG. The wavelengths were 248, 308, 511 and 578, 532, and 1064 nm. Pulses included a 250 ns long train of 0.1 ns pulses (mode-locked) and single pulses from 8 ns and 250 ns. The excimer lasers (KrF and XeCl) were found to give high quality scribes for all materials, including the transparent oxides, ZnO:Al and SnO2:F; however, vaporization rates were relatively low. Longer pulse durations (e.g., 90 ns) yielded higher rates of removal (up to 4 μm per J/cm2) for some materials. The high pulse energy available from the KrF laser allowed evaluation of beam delivery to a long narrow line which could eliminate the need for beam scanning and provide other advantages for scribing. We find that glass-side scribing, as opposed to film-side scribing, works well for Mo and CdTe films
Keywords :
Q-switching; excimer lasers; gas lasers; laser beam machining; semiconductor thin films; solar cells; solid lasers; 1 to 250 ns; 248 to 1064 nm; CdTe; Cu(InGa)Se2; KrF; KrF excimer laser; Mo; Q-switched lasers; Si; SnO2; SnO2:F; XeCl; XeCl excimer; YAG:Nd; YAl5O12:Nd; ZnO; ZnO:Al; copper vapor laser; flashlamp-pumped Nd:YAG lasers; high pulse energy; laser scribing; mode-locked lasers; polycrystalline thin-film PV materials; pulse duration effects; quasi-cw Nd:YAG laser; thin films; transparent oxides; vaporization rates; wavelength effects; Laser mode locking; Laser theory; Optical materials; Optical pulse shaping; Optical pulses; Pulsed laser deposition; Pump lasers; Semiconductor thin films; Transistors; Zinc oxide;
