Influence of precursor chemistry and growth temperature on the electrical properties of SrTiO3-based metal-insulator-metal capacitors grown by atomic layer deposition

Abstract

SrTiO 3 thin films were grown to thicknesses in the range of 18–30 nm by atomic layer deposition using Sr(Pir3Cp)2 and (CpMe5)Ti(OMe)3 as strontium and titanium precursors at 250 and 300 °C. Water or ozone was used as oxygen precursor. The films were amorphous in as-deposited state, but crystallized as cubic SrTiO3 after annealing at 650 °C. The highest permittivity values, 60–65, were achieved in the films deposited with ozone at 300 °C. The films grown at 250 °C tended to possess markedly lower leakage currents than those grown at 300 °C.

Influence of growth and annealing temperatures on the electrical properties of Nb2O5-based MIM capacitors

“…In the case of an as-deposited sample, the y-axis intercept is negative: the adjustment is not good (we have only three points available), the error covers the origin, so no conclusions can be obtained in this case. In a previous work with SrTiO 3based films (STO) we found different k-values for different film thicknesses as the crystallization intensities of these films were low for thinner films [19].…”

First-Principles Mechanistic Study of the Initial Growth of SrO by Atomic Layer Deposition on TiO2-Terminated SrTiO3 (001)

“…About two decades ago, deposition of conformal SrTiO 3 thin films by ALD at 325 °C was demonstrated using strontium bis­(cyclopentadienyl) [Sr­(Cp) 2 ] and titanium tetraisopropoxide as Sr and Ti precursors, respectively, and water as an oxidant. , After annealing in air at 500 °C, the deposited SrTiO 3 films were found to have measured permittivity values of around 180 . It has also been reported that the choice of precursors and oxidizers plays an important role in determining the quality of deposited thin films. , For instance, SrTiO 3 thin films deposited with [Sr­(demamp)­(tmhd)] 2 , titanium tetraisopropoxide, and O 3 exhibit dielectric constants of around 140 and acceptable leakage current densities . In many cases, reaction mechanisms underlying the ALD of perovskite oxides are still poorly understood, despite their importance.…”

“…12 It has also been reported that the choice of precursors and oxidizers plays an important role in determining the quality of deposited thin films. 25,26 For instance, SrTiO 3 thin films deposited with [Sr(demamp)-(tmhd)] 2 , titanium tetraisopropoxide, and O 3 exhibit dielectric constants of around 140 and acceptable leakage current densities. 9 In many cases, reaction mechanisms underlying the ALD of perovskite oxides are still poorly understood, despite their importance.…”