Significantly enhanced charge transport in polysilicon by alleviating grain boundary scattering through interface control using reduced graphene oxide

Here, we introduce interface control of polycrystalline silicon (poly-Si) using reduced graphene oxide (RGO) as a promising way to minimize the grain boundary scattering for the enhancement of the charge transport properties in poly-Si. In this experiment, Si powder was prepared by pulverizing an As-doped Si wafer using high-energy ball milling. The Si powder was coated with RGO, and the composite was consolidated by spark plasma sintering. The interface-controlled Si (Si–RGO) composite exhibited significantly enhanced charge transport properties compared with bulk poly-Si. The release of trapped electrons through interface control using RGO reduced the grain boundary barrier height and resulted in a negative temperature dependence of the mobility in the Si–RGO composite. Consequently, the mobility and carrier concentration of the Si–RGO composite were simultaneously enhanced through interface control using RGO.