| The effects of vacuum venting and material parameters were investigated in the injection molding of microscale features, specifically the replication quality of microscale features. A novel tooling was employed to fabricate microcircuits in polystyrene and polymethylmethacrylate materials. The replication of feature depth in the resultant parts correlated increased with vacuum level, with vacuum venting being more important for full replication of smaller features. The effects of melt temperature, mold temperature, and injection velocity on the depth of microscale features were less significant with vacuum venting. The overall shape of the molded features was also significantly enhanced with vacuum venting. With vacuum venting, melt viscosity and the melt's ability to wet the tooling surface influenced replication of microscale features. |
