聚焦离子束溅射刻蚀与增强刻蚀的性能研究

利用聚集离子束(F IB)对小线度下(≤3μm)的溅射刻蚀与增强刻蚀的性能进行了实验和分析。通过对硅和铝的刻蚀实验,研究在溅射刻蚀与增强刻蚀方法下刻蚀速率、蚀坑形貌与离子束流大小的关系。实验发现,铝和硅的刻蚀速率与刻蚀束流近似成线性关系;束流增大到一定程度后由于束斑变大及瞬时重淀积的作用,刻蚀速率曲线偏离线性。使用卤化物气体的增强刻蚀,硅和铝的刻蚀速率得到不同程度地提高。根据蚀坑形貌与束流大小的关系分析,发现瞬时重淀积是影响小线度刻蚀质量的主要因素。增强刻蚀大大减小了蚀坑的坑璧倾角,而坑底倾斜问题需综合考虑。

Investigation of Focused Ion Beam Sputtering Etching and Enhanced Etching

The fundamental properties of focused ion beams(FIB) sputtering teching and enhanced etching for Si and Al materials have been studied with shrinking dimensions(≤3 μm).The variation in etch rate and crater topography with ion current have been investigated.The etch rate of both materials increases linearly with the growth of ion current,until the ion current reaches 1 000pA.FIB enhanced etching using halide as an etchant leads to an increase in the material removal rate of silicon and aluminum by different factors.The slope angles of the side walls and the jut in the middle of the bottom of the crater have been observed by SEM imaging.The possible reasons of these results are discussed on the basis of sputtering mechanism.Using enhanced etch can achieve more regular crater.But the incline of the bottom of the crater caused by enhanced etch needs to be synthetically analyzed.