Frequency and voltage dependent dielectric properties of Ni-doped Ba0.6Sr0.4TiO3 thin films

Highly (100) preferred undoped and 1-5% Ni-doped Ba1-xSrxTiO3 (BST) thin films were deposited onto MgO (100) single crystal substrate at 750degreesC using pulsed laser deposition. BST thin film-based interdigital capacitors (IDC) were prepared by standard photolithography process. The microwave properties of BST films were measured at 10 GHz. Ni-doped BST films showed better dielectric properties by exhibiting improved dielectric Q while retaining an appropriate capacitance tuning compared to undoped BST films. 1% Ni-doped BST film showed the maximum figure of merit of 2896.1. It is suggested that 1 mol % Ni doped BST film is an effective candidate for high performance tunable device applications.