In this study, the pyroelectric coefficient and the figure of merit (FOM) of the ferroelectric (FE) PbZr0.3Ti0.7O3 (PZT 30/70) thin films were found to be greatly enhanced by introducing a thin antiferroelectric (AF) PbZr0.95Ti0.05O3 (PZT 95/05) layer underneath the FE film and thus creating a bilayer structure on platinized silicon substrates. The film properties were investigated as a function of the FE layer thickness when the thickness of AF layer remained unchanged. The highest pyroelectric coefficient of 1 μm thick PZT 30/70 film was 3.18×10-4 cm-2 K-1. However, the highest pyroelectric coefficient for 1 μm thick bilayer film was 3.5×10-4 or 2.5×10-4 cm-2 K-1 for only 280 nm thick bilayer film. The enhancement of pyroelectric coefficient suggests switching of AF into FE phase during poling and following stabilization of FE phase at room temperature. The reduction in dielectric constant in bilayer films after poling, compared to pure PZT 30/70, showed a FOM of 2.94×10-5 Pa-0.5, which is the double of the FOM for pure PZT 30/70 films of similar thickness (1.45×10-5 Pa-0.5).