Properties of BaTiO_3 Films Sputter Deposited on PET for Pulse Power Capacitors

摘要

Flexible BaTiO_3 films is dielectric materials for pulse power capacitors were deposited on polyethylene terephthalate (PET) substrates by r.f. magnetron sputtering. The growth behavior, microstructure and electrical properties of the flexible BaTiO_3 films were dependent on the O_2/Ar gas ratio during sputtering. All BaTiOj films were amorphous, regardless of the 0_2/Ar gas ratio, due to the low substrate temperature. The leakage current and dielectric constant of the BaTiOj films were affected by an electron transfer mechanism. The BaTiO_3 films prepared at an O_2/Ar gas ratio of 1 exhibited a dielectric constant of 53 at I kHz and a leakage current of 4×10~(-7) A at 500 kV/cm. This suggests that sputter-deposited flexible BaTiO_3 films are promising dielectrics that can be used in pulse power capacitors owing to their high dielectric constant, low leakage current and stable preparation by sputtering.