Photo-Machining produces about a 15° tapered side wall (bottom of opening will be smaller than top or entry). This limits the process to a 2:1 aspect ratio (hole to thickness) in lower density materials (glass & silicon), and 1:1 in higher density materials (silicon carbide, 96% alumina). See illustration below.
Although metals and plastics can be surface engraved or marked, they cannot be machined deeply due to their inherently ductile nature. Photo-Machining does work well to selectively remove micron thick layers (<.005”) of these materials such as copper-clad substrates or metal encapsulated ceramics.
PHOTO-MACHINING OPERATING PARAMETERS
NOTE: Through-holes/features can often be done from both sides to help straighten sidewalls. This will likely produce an hour-glass effect which may be beneficial in certain applications. |
