Sensitizer Aging Effects on Metalization and Imaging in the Photoselective Metal Deposition (PSMD) Process

Abstract

The PSMD imaging system employs aqueous SnCl 2 sensitizer solutions to generate electroless metal photopatterns on dielectric substrates. We have measured how aging in several typical sensitizer solutions affects their ability to generate electroless copper photopatterns on polyimide H film (DuPont Kapton®). Specimens, consecutively sensitized as the solution aged, have been characterized with respect to (i) tin deposition (by x‐ray fluorescence), (ii) catalytic activity for metalization (by optical density determination of the deposited electroless copper), and (iii) imageability (by image contrast measurements of the developed copper patterns). The system imageability is found highly dependent on the sensitizer solution age, while the capability for blanket metalization was relatively unaffected.