Characterization and electrical properties of high-k GdScO3 thin films grown by atomic layer deposition
Characterization and electrical properties of high-k GdScO3 thin films grown by atomic layer deposition
复制标题
DOI：
10.1007/s00339-007-4069-7
复制
发表时间：
2007-06
期刊：
影响因子：
--
通讯作者：
P. Myllymäki;M. Roeckerath;M. Putkonen;S. Lenk;J. Schubert;L. Niinistö;S. Mantl
中科院分区：
文献类型：
--
作者：
P. Myllymäki;M. Roeckerath;M. Putkonen;S. Lenk;J. Schubert;L. Niinistö;S. Mantl
氧化钪钪（Gd-钪酸盐，GdScO3）薄膜是通过原子层沉积（ALD）从β-二酮前体M(thd)3（M=Gd, Sc; thd=2,2,6,6-四甲基-3,5-庚二酮）和臭氧中生长的。对沉积参数进行优化，以生产化学计量比为 1:1 的金属比的薄膜，并制备了一系列标称厚度为 5、10、15 和 20 nm 的样品。在 300°C 下，金属前驱体脉冲比率 Gd:Sc=5:6 产生非晶化学计量薄膜，生长速率为 0.21 Å/周期。在高达 900°C 的温度下，薄膜仍保持非晶态。使用 AFM 探测表面，发现 5-20 nm 厚的薄膜的均方根粗糙度为 0.3 nm。事实证明，沉积薄膜的电性能非常有前景，在 -2 V 下测得的介电常数为 ∼22，漏电流密度为 340 μA/cm2。
Gadolinium scandium oxide (Gd-scandate, GdScO3) thin films were grown by atomic layer deposition (ALD) from β-diketonate precursors M(thd)3(M=Gd, Sc; thd=2,2,6,6-tetramethyl-3,5-heptanedionato) and ozone. The deposition parameters were optimized to produce films with the stoichiometric 1:1 metal ratio and a series of samples with nominal thicknesses of 5, 10, 15, and 20 nm were prepared. At 300 °C the metal precursor pulsing ratio Gd:Sc=5:6 yielded amorphous stoichiometric films and a growth rate of 0.21 Å/cycle. The films stayed amorphous up to 900 °C. The surface was probed with an AFM and the rms roughness was found to be 0.3 nm for the 5–20 nm thick films. The electrical properties of the as-deposited films proved to be very promising, with a dielectric constant of ∼22 and leakage current density of 340 μA/cm2, measured at -2 V.