Interaction of coimplanted heterogeneous dopants in semiconductor materials investigated using three-dimensional atom probe

通过在半导体中共注入非均相掺杂剂形成浅结，实现大规模集成的连续收缩是近年来备受关注的问题。在这项研究中，研究了碳和硼原子在硅衬底中的共植入行为。用三维原子探针直接观察了退火后形成的碳硼共团簇。结合扩展电阻测量得到的载流子浓度分布，发现碳共注入导致硼电活化降低，而碳原子的存在抑制了硼的扩散。为了校准原子探针获得的三维重建图像，使用了原子层沉积制备的同位素多层样品。

Coimplantation of heterogeneous dopants into semiconductors for shallow junction formation has recently been attracting much attention for realizing continuous shrinkage of large-scale integration. In this study, the behavior of coimplanted carbon and boron atoms in silicon substrates is investigated. The carbon-boron coclusters formed by annealing were directly observed by three-dimensional atom probe. In combination with carrier concentration profiles obtained by spreading resistance measurements, it is found that the carbon coimplantation leads to the decrease of boron electrical activation, whereas boron diffusion is suppressed by the presence of carbon atoms. For calibrating the three-dimensional reconstructed images obtained by the atom probe, isotopic multilayer samples fabricated via atomic-layer deposition were employed.