Alternative process for thin layer etching: Application to nitride spacer etching stopping on silicon germanium
Alternative process for thin layer etching: Application to nitride spacer etching stopping on silicon germanium
复制标题
薄层蚀刻的替代工艺：应用于停止在硅锗上的氮化物间隔蚀刻
DOI：
10.1063/1.4892543
复制
发表时间：
2014
影响因子：
4
通讯作者：
S. Barnola
中科院分区：
文献类型：
--
作者：
N. Possémé;O. Pollet;S. Barnola
Silicon nitride spacer etching realization is considered today as one of the most challenging of the etch process for the new devices realization. For this step, the atomic etch precision to stop on silicon or silicon germanium with a perfect anisotropy (no foot formation) is required. The situation is that none of the current plasma technologies can meet all these requirements. To overcome these issues and meet the highly complex requirements imposed by device fabrication processes, we recently proposed an alternative etching process to the current plasma etch chemistries. This process is based on thin film modification by light ions implantation followed by a selective removal of the modified layer with respect to the non-modified material. In this Letter, we demonstrate the benefit of this alternative etch method in term of film damage control (silicon germanium recess obtained is less than 6 A), anisotropy (no foot formation), and its compatibility with other integration steps like epitaxial. The etch mechanisms of this approach are also addressed.
