Effect of Post-Baking Treatment Conditions on the Interfacial Adhesion Energy between Electroless-Plated Ni and Polyimide Films

Effects of Temperature and Humidity Treatment Conditions on the Interfacial Adhesion Energy between the Electroless-Plated Ni and Polyimide

“…In general, interfacial adhesion between metal thin film and polymer substrate decreases after temperature/ humidity treatment. [9][10][11][12]18,22) In this result, electroless-plated Ni/polyimide system shows steep decrease in peel strength after 168 h temperature/humidity treatment. This means weaker interfacial adhesion strength, and therefore, it can be related to the specific interfacial boundary layer relevant to polyimide surface wet pretreatment, which causes degradation of the polyimide itself by the interfacial reaction with humidity.…”

“…13) Generally, there are three types of failure paths in metal thin film/polyimide substrate systems. One is the interfacial failure locus which occurs along the metal/polyimide interface, 9,18,19) and the second is the cohesive failure locus which occurs in the inside of the polyimide near the metal/polyimide interface. [19][20][21] And the last is the mixture mode of interfacial and cohesive failure.…”

“…Generally, interfacial delamination during peel test occurs near weak adhesion layers for metal-polymer systems. [9][10][11][12]18,22) The vertical peel cracks from peeling direction with narrow spaces are observed at peeled metal surface when there is strong interface adhesion strength, while wide spaces of peel crack are observed for weak interfacial adhesion strength. In our result, peel crack at the peeled metal surface was not observed because the cohesive failure occurs inside the polyimide near Ni/polyimide interface.…”