Patent ID: 9221124
Filing Date: 2015-12-29
Classification: B23K

Abstract:
1. A method of cutting a work piece including one or more layers formed over a substrate, the method comprising: generating a beam of laser pulses; shaping the generated beam of laser pulses only through diffraction to produce spatial irradiance profiles with flattened tops, wherein the shaping produces, at the work piece, a series of laser spots with edges that are flattened, each including an asymmetrical aspect ratio with a first dimension being longer than a second dimension, the shaping spatially spreading the energy of each of the laser pulses as the aspect ratios of the respective laser spots change from symmetrical to asymmetrical; aligning the longer first dimension of each laser spot in a cutting direction along the work piece so as to distribute the energy of each laser pulse in the cutting direction; and providing relative movement, in the cutting direction, between the beam and the work piece so as to scribe a kerf in the one or more layers, the kerf passing through the one or more layers to a top surface of the substrate.