We report the control of self-polarization of monocrystalline Lead Zirconate Titanate thin films grown by Pulsed laser deposition by doping and bottom interface. Doped and undoped films grown on ScO2 terminated surface of polar PSO substrate have developed polarization oriented toward the substrate due to negative polarity (ScO-) of the substrate termination. For films grown on the strontium ruthenate (SRO) bottom electrode, only undoped and 1% Nb doped PZT films have developed upwards oriented self-polarization. The introduction of strontium ruthenate bottom electrode have made the work function difference between films and bottom electrode to be the dominant mechanism for self-polarization.