Low-temperature process in growing carbon nanotube

Nickel particles, converted from film by microwave hydrogen plasma at a low temperature of 250 °C, were used as the catalyst for growing carbon nanotubes (CNTs). Low-temperature process is desirable for CNT application in flat panel display industry. We found that the processing pressure and microwave power can greatly influence the nickel particle size and density. The processing pressure during pretreatment affects the CNT to be grown or not at all. The microwave power affects the particle size of the catalyst and the diameter of the grown CNT. It was also found that after pretreatment, the diameter of the grown CNT is proportional to the catalyst particle size. The threshold electric field of CNT field emission was found reduced as the diameter of the CNT became smaller.