Preheat of Photoresist to Reduce Ripple Formation During Lamination
Original Publication Date: 1985-Jun-01
Included in the Prior Art Database: 2005-Feb-18
The photoresist lamination process for the construction of a printed circuit board, or the like, requires the use of heat and pressure. The heat causes the photoresist system to expand, but because of tension the system is unable to expand freely. The constrained expansion produces ripples which become part of the resist topography. The reduction of this ripple formation is accomplished by heating the photoresist before contact is made with the laminating rollers. The resulting topography is more uniform and has fewer photoresist defects.