Sputter-deposited PZT on patterned silicon optimization for C-band electro-optic modulation

We report the optimization methodology of sputter-deposited lead zirconium titanate (PZT) on a silicon-on-insulator platform for photonic applications. A crack-free PZT film is obtained for a 3.6°C/min ramp rate, 550°C annealing temperature, and a surface roughness of ≈2nm, ≈5nm, and ≈10nm for PZT grown on MgO, Pt, and TiO 2 buffers, respectively. The coercive field for PZT/MgO and PZT/Pt film is 50 kV/cm and 30 kV/cm, respectively. A waveguide loss of 6.5 dB/mm is obtained for PZT-on-silicon (Si) waveguides. An electro-optic device using an Si microring resonator with optimized PZT/MgO is demonstrated with electro-optic response and coercive field of 14 pm/V and 50 kV/cm, respectively.