A study of laser etching and cutting PCB boards by 355nm DPSS UV laser

AbstractUltraviolet laser-induced, radical-etching processes developed by us can provide practical etch rates and selectivities for most of the important film layer combinations used in silicon microelectronic devices. These processes have been demonstrated in simple proximity and projection exposure experiments to produce etch features on surfaces with dimensions of a few tenths of a micrometer.Mechanistic studies suggest that, in our etching processes for polysilicon and molybdenum, fluorine atoms responsible for etching are primarily produced from the precursors COF2 and NF3 on the surface rather than in the gas phase. The predominant production process appears to be photodecomposition of surface adsorbed precursor. Contributions due to precursor pyrolysis or precursor reaction with photogenerated charge carriers are found to be unimportant.

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Low temperature UV laser etching of PMMA: On the mechanism of ablative photodecomposition (APD)

Journal of Polymer Science Part C Polymer Letters ◽

10.1002/pol.1986.140240802 ◽

1986 ◽

Vol 24 (8) ◽

pp. 371-376 ◽

Cited By ~ 12

Author(s):

B. Braren ◽

D. Seeger

Keyword(s):

Low Temperature ◽

Uv Laser ◽

Laser Etching

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Comparison of CW and Pulsed UV Laser Etching of LiNbO3

MRS Proceedings ◽

10.1557/proc-129-321 ◽

1988 ◽

Vol 129 ◽

Cited By ~ 3

Author(s):

K.W. Beeson ◽

N.S. Clements

Keyword(s):

Lithium Niobate ◽

Laser Beam ◽

Excimer Laser ◽

Uv Laser ◽

Laser Etching ◽

Argon Ion Laser ◽

Ion Laser ◽

Argon Ion

ABSTRACTThe results of CW frequency-doubled argon-ion laser etching and pulsed excimer laser etching of lithium niobate (LiNbO3) are compared. Argon-ion laser etching occurs in the presence of Cl2 at laser intensities of 1.1 MW/cm2 or higher. The 257 nm laser beam with up to 25 mW power is focused to a 1.5 μm diameter spot and scanned at speeds of 10 μm/s or less. Excimer laser etching is done at 248 nm (KrF) with the laser beam focused onto the sample with cylindrical optics. Trenches <20 μm wide and several millimeters long are produced by ablating the target and without scanning the beam. Excimer laser etching of lithium niobate has been attempted in the presence of C12, O2, N2, H2 or air. Excellent results are obtained with air as the etching medium.

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