Abstract
This research is to form high-density, high-conductivity carbon nanotube-like (CNT-like) structures for nano-interconnect application. The effect of amorphous carbon (a-C) characteristics on CNT-like formation was investigated by using C2H2 or CH4 as a reaction gas for a-C deposition with various C2H2/H2 and CH4/H2 ratios. Besides, the feasibility of selective CNT-like structures formation from the a-C film with patterned catalysts underneath was studied so as to form the nano-interconnect composed of insulating a-C and conducting CNT-like structures. In this research, 248 nm KrF excimer laser light was exposed on the substrates with a-C(30 nm)/Ni(10 nm)/Ti(10 nm) on top for 10 s at 1 Hz to form CNT-like structures. Higher quality of CNT-like structures is achieved at laser energy density ramped from 46 mJ/cm2 to 36 mJ/cm2 gradually. The effect of a-C characteristics on the formation of CNT-like structures was investigated at laser condition as above. It was found that C2H2-deposited a-C films were more suitable for formation of CNT-like structures. Increasing the C2H2/H2 ratio can also improve the quality and adhesion of CNT-like structures on substrates. The a-C films with patterned Ni/Ti catalyst underneath were deposited on SiO2/Si to verify the feasibility of forming CNT-like structures selectively by laser direct writing for the formation of nano-interconnect consisting of insulating a-C and conducting CNT-like structures.