Electrical properties of sputter deposited SrTiO3 gate dielectrics

Effect of O2/Ar flow ratio and post-deposition annealing on the structural, optical and electrical characteristics of SrTiO3 thin films deposited by RF sputtering at room temperature

“…Dawber et al [49] defined this kind of a butterfly loop, where the capacitance is different for increasing or decreasing voltages, as one of the important ferroelectric material charcateristics. However, in the literature, the butterfly loop was mostly attributed to charge injection, and carrier trapping and/or space charge redistribution in the under electrode area, or net positive charges which cause a positive shift during the voltage sweep [49,50]. Furthermore, it might also be explained by the switching of ferroelectric domains [49].…”

Electro‐optical performances of nanostructured SrTiOx films: The effect of plasma power, Ar/O2 ratio and annealing

“…The DC bias voltage is swept from negative voltage to positive voltage for C – V measurements. At large negative gate voltage region, the capacitances of the STO dielectric films are dominant in the total capacitance, indicating accumulation 42,43 . After the determination of the accumulation voltage, C – f of the films was measured.…”

“…At large negative gate voltage region, the capacitances of the STO dielectric films are dominant in the total capacitance, indicating accumulation. 42,43 After the determination of the accumulation voltage, C-f of the films was measured. In strong accumulation region, using the maximum capacitance of the films, C, the dielectric constant of the film, ε r, can be calculated from the formula given in the experimental section.…”

“…The increase in the dielectric constants of films deposited at 100 W plasma power with increased OMR values may be due to the higher oxygen incorporation in the films and the densification of the films after the annealing process. 43 Furthermore, the reason for the as-deposited films having lower dielectric constant than deposited at annealed samples might be attributed to the thicker interfacial layer in as-deposited samples, or amorphous nature of the grown films. Sakabe et al studied the grain size effects on dielectric properties of BaTiO 3 ceramics, and reported that the dielectric constant increases with crystallite size.…”

Growth and characterization of nanocrystalline SrTiOxfilms: room temperature deposition using RF sputtering system in a pure argon environment

“…They indicated that the effect might be the result of the switching mechanism of the ferroelectric domains in nanocrystal regions [39]. Other reports in the literature attribute this behaviour to the charge injection, carrier trapping and/or space charge redistribution in the under electrode area, or net positive charges creating a positive shift during the voltage sweep [21,39]. In our work, the cause for this difference is unknown and further investigations, such as electric field dependent polarity or pulsed C-V measurements, are required to better understand this phenomenon.…”