Method for controlling configuration of laser induced breakdown and ablation

• Main Authors: ELNER; VICTOR, KURTZ; RON, SQUIER; JEFFREY A, LICHTER; PAUL R, DUTTA; SUBRATA K, LIU; XINBING, MOUROU; GERARD A, DU; DETAO, PRONKO; PETER P
• Format: Patent
• Language: English
• Published: 12.08.1997
• Edition: 6
• Subjects: BANDAGES, DRESSINGS OR ABSORBENT PADS; BASIC ELECTRIC ELEMENTS; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF,TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; DEVICES USING STIMULATED EMISSION; DIAGNOSIS; ELECTRICITY; FILTERS IMPLANTABLE INTO BLOOD VESSELS; FIRST-AID KITS; FOMENTATION; HUMAN NECESSITIES; HYGIENE; IDENTIFICATION; MACHINE TOOLS; MEDICAL OR VETERINARY SCIENCE; METAL-WORKING NOT OTHERWISE PROVIDED FOR; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; PERFORMING OPERATIONS; PROSTHESES; SOLDERING OR UNSOLDERING; SURGERY; TRANSPORTING; TREATMENT OR PROTECTION OF EYES OR EARS; WELDING; WORKING BY LASER BEAM

In one aspect the invention provides a method for laser induced breakdown of a material with a pulsed laser beam where the material is characterized by a relationship of fluence breakdown threshold (Fth) versus laser beam pulse width (T) that exhibits an abrupt, rapid, and distinct change or at least a clearly detectable and distinct change in slope at a predetermined laser pulse width value. The method comprises generating a beam of laser pulses in which each pulse has a pulse width equal to or less than the predetermined laser pulse width value. The beam is focused to a point at or beneath the surface of a material where laser induced breakdown is desired. The beam may be used in combination with a mask in the beam path. The beam or mask may be moved in the x, y, and Z directions to produce desired features. The technique can produce features smaller than the spot size and Rayleigh range due to enhanced damage threshold accuracy in the short pulse regime.