Patent ID: 6566628
Filing Date: 2003-05-20
Classification: B23K,H01L

Abstract:
A device for ablating at least one thin-film layer selected from the group including a front electrode, an absorber layer and a back electrode of a substrate of a workpiece, comprising:a laser resonator for generating a light pulse machining beam having pulse durations smaller than 100 ns and a pulse energy density in a range 0.1 J/cm2 to 10 J/cm2; an optical system arranged in a path of the machining beam, the optical system including a mode-mixing optical fiber cable and an optical imaging member for imaging an output of the optical fiber cable on a surface of the workpiece to be machined, wherein the optical system produces, in a plane of the surface to be machined, a power distribution in a surface area range of 1 mm2 to 1 cm2 that is substantially homogenous; and a positioner, controllable by a controller, for positioning the workpiece relative to the machining beam such that for a relative movement an amount of energy impinging the surface to be machined is substantially constant for each unit of surface area.