Mechanical Testing of Blind Vias
Original Publication Date: 1984-Jun-01
Included in the Prior Art Database: 2005-Feb-04
A test to measure the force that is necessary to separate blind vias from circuit board interplans is accurately performed in the following four-step procedures: Step One: Cut a small area around the via 1 to be tested (including its pad P In the interplane) and remove from board. Cut all circuit lines near the via, and immerse the via 1 in concentrated sulfuric acid at 185ŒF. After 30 minutes remove and separate all glass cloth from the via. Step Two: Insert pin 2 in a mount (not shown) and apply adhesive 3 to the head of the pin. Place the via in an upright position on the adhesive, and let it set for 30 minutes. Next, place a drop of oil 4 on the upper surface 7 of via pad P. Step Three: Place nut 5 on a glass slide (not shown) and fill the nut with molding compound 6.