The interfacial structure between SU-8 photoresist and Ni substrate was constructed by using molecular dynamics (MD) simulation software Materials Studio.The influence of postbaking temperature on the interfacial binding property was studied.According to postbaking temperature adopted by experimental process

cross-linking reaction of SU-8 photoresist was performed at different postbaking temperatures within 338～368 K.Several circles of energy minimization (MM) and MD simulation were applied to the interfacial structure.The binding energy was calculated after the interfacial system getting equalization.It can be seen that with increasing the postbaking temperature the binding energy of the interface between SU-8 photoresist and Ni substrate becomes larger.The value of the binding energy achieved maximum at 368 K.So it can draw the conclusion that the binding property is best at this temperature.By analysing the energy of the molecular system

it can be found that the key influencing factor for the interfacial adhesion is van der Waals force between interface molecules.Pair correlation function (PCF) between atoms of the interfacial structure was analysed.Two strong peaks were found in the range of 0.31 nm to 0.6 nm which belonged to the range of van der Waals force.