Eom Kitae, Kim Taemin, Seo Jiwon, Choi Jaedu, Lee Jaichan
J Nanosci Nanotechnol. 2014 Nov;14(11):8762-5. doi: 10.1166/jnn.2014.10012.
We have grown Sr0.75La0.25TiO3 (SLTO) thin films using pulsed laser deposition (PLD) with various laser energy fluences. We investigated the effect of energy fluence on the compositions of SLTO films. The stoichiometry of SLTO films was controlled by adjusting the laser energy density. At low energy densities below 1.0 J/cm2, SLTO films become non-stoichiometric with Ti deficiency. The Ti deficiency increases with decreasing the laser energy fluence. We have also investigated the effect of laser energy fluence on the electrical properties of the thin films. The electrical resistivity and carrier density intimately depend on the laser energy fluence as a result of the non-stoichiometry. After eliminating the effect of oxygen vacancies by post-annealing, the electrical properties are dependent on the cation stoichiometry in the oxide films.
我们使用脉冲激光沉积（PLD）技术，在不同的激光能量密度下生长了Sr0.75La0.25TiO3（SLTO）薄膜。我们研究了能量密度对SLTO薄膜成分的影响。通过调整激光能量密度来控制SLTO薄膜的化学计量比。在低于1.0 J/cm2的低能量密度下，SLTO薄膜会出现Ti缺失，从而变得非化学计量。Ti缺失随着激光能量密度的降低而增加。我们还研究了激光能量密度对薄膜电学性能的影响。由于非化学计量比，薄膜的电阻率和载流子密度密切依赖于激光能量密度。通过退火消除氧空位的影响后，电学性能取决于氧化物薄膜中的阳离子化学计量比。
