Abstract: Numerous embodiments are disclosed. Many of which relate to methods of forming vias in workpieces such as printed circuit boards. Some embodiments relates techniques for indirectly ablating a region of an electrical conductor structure of, for example, a printed circuit board by spatially distributing laser energy throughout the region before the electrical conductor is indirectly ablated. Other embodiments relate to techniques for temporally-dividing laser pulses, modulating the optical power within laser pulses, and the like.

Abstract: Apparatus and techniques for laser-processing workpieces can be improved, and new functionalities can be provided. Some embodiments discussed relate to use of beam characterization tools to facilitate adaptive processing, process control and other desirable features. Other embodiments relate to laser power sensors incorporating integrating spheres. Still other embodiments relate to workpiece handling systems capable of simultaneously providing different workpieces to a common laser-processing apparatus. A great number of other embodiments and arrangements are also detailed.

Abstract: A method for forming features in a substrate includes irradiating a substrate with a beam of laser pulses, wherein the laser pulses have a wavelength selected such that the beam of laser pulses is transmitted into an interior of the substrate through a first surface of the substrate. The beam of laser pulses is focused to form a beam waist at or near a second surface of the substrate, wherein the second surface is spaced apart from the first surface along a z-axis direction, and the beam waist is translated in a spiral pattern extending from the second surface of the substrate toward the first surface of the substrate. The beam of laser pulses is characterized by a pulse repetition rate in a range from 20 kHz to 3 MHz, a pulse duration, a pulse overlap, and a z-axis translation speed.