Drilled Epoxy Hole Smear Detection Technique
Original Publication Date: 1984-Sep-01
Included in the Prior Art Database: 2005-Feb-05
A method to identify and determine the magnitude of drill smear in multilayer printed circuits is described in the following three step procedure. I. Sample sections are cut to size on a wafering saw which has a metal disk diamond-impregnated cutting edge of 4" in diameter. Align the blade approximately 1/3 of the way into the hole diameter, and cut through the sample leaving 2/3 of the hole remaining. Using 600 grit sandpaper, abrade sample under running water until approximately 50% of the hole remains. Rinse sample under water, then in isopropanol, and gently blow dry. Microscopically examine the sample for any residual debris left in holes.