The effect of oxygen incorporation in sputtered scandium nitride films
The effect of oxygen incorporation in sputtered scandium nitride films
复制标题
DOI：
10.1016/j.tsf.2008.05.050
复制
发表时间：
2008-10-01
期刊：
影响因子：
2.1
通讯作者：
Humphreys, C. J.
中科院分区：
文献类型：
--
作者：
Moram, M. A.;Barber, Z. H.;Humphreys, C. J.
采用反应磁控溅射法在蓝宝石衬底上沉积了半导体氮化钪薄膜。通过在引入反应性Ar/N-2溅射气体混合物之前增加沉积室中的残余基础压力，将增加浓度的氧引入到ScN膜中。即使当使用10（-6）Pa的基础压力沉积时，膜也显示出显著的氧污染。污染水平的增加降低了薄膜的结晶质量。氧污染也有助于膜电阻率与温度的非阿耳忒弥斯行为，并最终导致在ScN膜中的简并n型导电性。氧掺入ScN增加了直接带隙从2.2 eV到3.1 eV，因此可能是一个促成的原因，为宽范围的直接带隙实验确定的这种材料。与在类似条件下沉积的TiN和ZrN膜的比较表明，ScN显示出相对较高的氧亲和力。这些结果意味着，具有高的结晶质量和非退化的电性能的氮化钪薄膜的生产需要使用的沉积技术，涉及超高真空条件或其他低氧环境。(c)2008 Elsevier B. V.保留所有权利。
Thin films of the semiconductor scandium nitride were deposited onto sapphire substrates using reactive magnetron sputtering. Increasing concentrations of oxygen were introduced into the ScN films via increasing the residual base pressure in the deposition chamber prior to introduction of the reactive Ar/N-2 sputtering gas mixture. Films showed significant oxygen contamination even when deposited using base pressures of 10(-6) Pa. Increasing levels of contamination degrade the crystalline quality of the films. Oxygen contamination also contributes to the non-Arrhenius behaviour of film resistivity versus temperature and ultimately results in degenerate n-type conductivity in the ScN films. Oxygen incorporation in ScN increases the direct band gaps from 2.2 eV to 3.1 eV and may therefore be a contributing reason for the wide range of direct band gaps experimentally determined for this material. Comparison with TiN and ZrN films deposited under similar conditions shows that ScN displays a comparatively high oxygen affinity. The results imply that the production of ScN films possessing high crystalline quality and non-degenerate electrical properties requires the use of deposition techniques involving ultra-high vacuum conditions or other low-oxygen environments. (c) 2008 Elsevier B.V. All rights reserved.