METHOD FOR UNIFORMLY CUTTING CARBON NANOTUBES, COMPRISING PATTERNING OF CARBON NANOTUBES BY PHOTOLITHOGRAPHY

摘要

PURPOSE: Provided is a method for uniformly cutting carbon nanotubes by patterning of carbon nanotubes through lithographic process, and removing unexposed carbon nanotube portions by reactive ion etching. CONSTITUTION: The carbon nanotubes are uniformly cut by the following steps of: (i) forming a carbon nanotube thin film on a quartz substrate through self-assembling process of carbon nanotubes by dispersing carbon nanotubes into a solvent, immersing the substrate in the solvent and vaporizing the solvent, or coating process such as spin coating, dip coating and spray coating, and preferably spin coating by coating 0.002-80wt.% of carbon nanotube coating solution in a rate of 100-10,000rpm for 1sec-10min, wherein the substrate is treated with a material, expressed by the formula X-R (X: functional group, R: space moiety), such as 1-decanthiol, 1-dodecylthiol, nonylamine, dodecylamine or 4-pentadecyl aniline, and the solvent is methylisobutylketone, tetrahydrofuran, ethyl acetate, ethyl alcohol or dimethyl formamide; (ii) thermal-hardening a carbon nanotube film at 25-200deg.C for 5sec-30min; (iii) coating photoresist on the carbon nanotube film by spin coating at a rate of 10-10,000rpm for 0.5sec-30min and forming a pattern through photolithography by radiating 50-500ml/cm2 of ultraviolet rays(=500nm) and post exposure baking(PEB) at 100deg.C for 1sec-30min; (iii) reactive ion etching the patterned carbon nanotubes with CF4 and O2 gas for 1sec-30min for cutting carbon nanotubes; (iv) removing photoresist remaining on the cut nanotubes with the solvent used in forming of carbon nanotube film; (v) dispersing resultant carbon nanotubes in the solvent, filtering and oven-drying at 30-500deg.C for 5min-72hrs.