Abstract: A method for producing feedthroughs in a substrate having a front and back surface, wherein the substrate either has a hole or absorbs radiation at a given wavelength. The method includes selecting and intimately bonding a sheet to the back surface of the substrate with an adhesive which is absorptive at the given wavelength. If the substrate has a hole, an exposed area of the sheet is illuminated with laser radiation at the given wavelength and at a power level sufficient to ablate a portion of the sheet behind the exposed area, thereby creating the feedthrough in the substrate. If the substrate has no hole, an area on the front surface of the substrate is illuminated with laser radiation at the given wavelength and at a power level sufficient to ablate a portion of the substrate and a portion of the sheet behind the area, thereby creating the feedthrough in the substrate. The sheet can then be removed from the substrate.