On Preparation of SrTiO<sub>3</sub> Thin Films with Self-Assembled Monolayers by Liquid Phase Deposition and its Dielectric Properties

Abstract

In this paper, titanium ammonium fluoride ((NH4)TiF6), strontium nitrate (Sr(NO3)2) and boric acid (H3BO3) were used as raw materials, the precursor solution was prepared with molar ratio of AHFT/SN/BA=1/1/3. SrTiO3 dielectric thin films were deposited with the self-assembled monolayers (SAMs) by the liquid-phase deposition on FTO substrate. X-ray diffraction (XRD), scanning election microscopy (SEM) and Agilent E4980A precision LCR Meter were used to characterize the SrTiO3 films. The precursor solution concentration and the pH values of precursor solution had the effects on the dielectric properties of the as-prepared thin films. When the precursor concentration was 0.0125mol/L, the crystallization of as-prepared SrTiO3 thin films was high and the grain sizes on the film surface were even and dense. When the frequency was 15~100KHz, the optimal dielectric constant was up to 1060, the minimal dielectric loss was 4.053. As pH=3.30, the frequency of the as-prepared SrTiO3 thin films was 15~100KHz. The optimal dielectric constant was up to 1060, too. The minimal dielectric loss was 1.914. The optimal dielectric constants were 346.3 and 424.1 when the pH was 3.1 and below 3.5 respectively. The minimal dielectric losses were respectively 18.10 and 54.82.