Effect of curing conditions on the fabrication of Zn-oxide nanoparticles dispersed in a polyimide film

Zinc oxide nanoparticles were formed by reacting polyamic acid (PAA) with Zn during curing. In this paper, we investigated the effect of curing conditions on the zinc oxide nanoparticle formation. The polyimide (PI) precursors used in this study were biphenyltetracarboxylic dianhydride-p-phenylene diamine (BPDA-PDA) type and oxydiphthalic dianhydride 3-sulful dianhydride (ODPA-3SDA) type PAAs. Zn thin films were deposited on silicon substrates by DC magnetron sputter. PAA was then spin-coated onto Zn thin films and the PAA/metal films were cured at various conditions. The characterization using transmission electron microscope observation was carried out to investigate the size and distribution of zinc oxide particles. Zinc oxide nanoparticles were formed in the PI film regardless of the curing conditions. The size, distribution and density of zinc oxide particles were strongly dependent on the curing conditions.