Room Temperature Fabrication of MIMCAPs via Aerosol Deposition

We report the microwave dielectric properties of BaTiO
₃
thin films fabricated via aerosol deposition, which is capable of applying functional ceramic films to Si-based semiconductor fabrication at room temperature. As the starting powder, BaTiO
₃
powder with an average particle size of 300 nm afforded a dense thin film with a thickness of 500 nm as well as a smooth interface with the Pt/Ti/SiO
₂
/Si substrate. In comparison, the interface roughness of BaTiO
₃
thin film was degraded (>100 nm) when BaTiO
₃
powder with an average particle size of 450 nm was used as the starting powder, owing to the excessive impact energy during film growth. Metal-insulator–metal capacitors were realized on a Si wafer via electron beam evaporation and inductively coupled plasma etching in order to determine the relative permittivity, loss tangent, and current-voltage characteristics. The average values of the relative dielectric permittivity and loss tangent of the BaTiO
₃
thin film were 78 and 0.03, respectively, in the frequency range of 1–6 GHz.