Implementing reduced drill smear

摘要

A method is provided for implementing reduction of drill smear in drilling a multilayer substrate such as a rigid printed circuit board or flex to minimize or eliminate the need to remove drill smear and for improved via and interconnect reliability. An inert liquid is applied to the multilayer substrate and a drill bit prior to and during the drill process to cool and lubricate the multilayer substrate and the drill bit to reduce drill smear.

主权项

1. A method for reducing drill smear, the method comprising:
providing a multilayer substrate including dielectric materials configured to provide signal integrity performance; and applying an inert liquid to the multilayer substrate and a drill bit prior to and while drilling the multilayer substrate to cool and lubricate the multilayer substrate and the drill bit, wherein cooling the multilayer substrate and the drill bit reduces drill smear within the multilayer substrate, and the inert liquid is a fluorocarbon polymer of polyhexafluoropropylene oxide having a chemical formula of:F—(CF(CF3)—CF2—O)n-CF2CF3, with n in a range of 10 to 60.