High-temperature pretreatment of Ni nanoparticles enhances the growth of high-density carbon fiber bundles during microwave plasma chemical vapor deposition

► We evaluated the pretreatment procedure of Ni nanoparticles (NPs) on the growth of multiwalled carbon nanotube (MWCNT) bundles by means of microwave plasma chemical vapor deposition (MPCVD). ► The diameter and shape of the Ni NPs were the dominant factors affecting the size and density of the MWCNT bundles. ► We obtained MWCNTs that fully filled the via effectively; they might serve as potential interconnects in future nanodevices. This paper presents an experimental study on the effect of the pretreatment procedure of Ni nanoparticles (NPs) on the growth of multiwalled carbon fiber (CNF) bundles by means of microwave plasma chemical vapor deposition (MPCVD). We used atomic force microscopy to investigate a series of pretreated Ni films. The structures and compositions of the CNFs on the via were investigated using scanning electron microscopy, high-resolution transmission electron microscopy, and Raman spectroscopy. The geometric shape of the Ni NPs was identified in terms of their roughness, which decreased upon increasing the pretreatment temperature, resulting subsequently in the synthesis of high-density CNFs. The diameter and shape of the Ni NPs were the dominant factors affecting the size and density of the CNFs bundles. We obtained CNFs that fully filled the via effectively; they might serve as potential interconnects in future nanodevices.