Growth of high-density horizontal SWNT arrays using multi-cycle in-situ loading catalysts

Density of horizontal single-walled carbon nanotube (SWNT) array is considered as one of most important index in SWNT-based integrated circuits. However, it is still a challenge to directly obtain horizontal SWNT arrays with ultra-high density on quartz. Herein, we developed multi-cycle in-situ loading catalysts method to directly grow horizontal SWNT arrays with high density on quartz substrate. In this method, Cu catalysts showed much higher efficiency to grow SWNT, which were in-situ loaded through depositing Cu vapor produced by hot copper mesh. Density and size of catalysts could be directly controlled by depositing temperature and time. Moreover, the high efficiency of in-situ loaded Cu catalysts can be maintained after multi-cycle loading, which leads to the linear increase of SWNTs density with loading times. Finally, further optimizing depositing temperature and time, horizontal SWNT arrays with the average density higher than 60 SWNTs/mu m and area larger than 8 x 12 mm on quartz have been obtained. This method opens up an opportunity for obtaining SWNT arrays with any density, which shows great potential in the nanoelectronics application in the future. (C) 2019 Elsevier Ltd. All rights reserved.