A comparative analysis of transistors based on dielectrophoresis-aligned carbon nanotubes (CNTs) and assembled random-network CNTs

The purpose of this project is to investigate the fabrication and characterization of carbon nanotube (CNT) thin-film transistors (TFTs), based on two solution-based fabrication methods: dielectrophoretic deposition of aligned CNTs and self-assembly of random-network CNTs. The fabrication procedures of the two transistors and their corresponding electrical characteristics are studied comparatively. The electrode design enables repeatable CNT thin-film deposition and results in transistors with comparable structures. Electrodes are fabricated on low-resistivity Si/SiO ₂ wafers using lithography and wet etching. The measurement results of these two CNT transistors are compared to determine the differences in electrical characteristics. The results indicate that the self-assembly method produces a stronger field effect. This phenomenon can be further enhanced in future work by decreasing the concentration of metallic CNTs (mCNTs) through a number of different methods.