Localized Synthesis of Carbon Nanotube Films on Suspended Microstructures by Laser-Assisted Chemical Vapor Deposition
A laser-assisted chemical vapor deposition (LCVD) method has been developed for in situ synthesis of carbon nanotube (CNT) films on suspended microstructures. Focused laser beams are used to heat locally the suspended microstructures with low thermal mass and low thermal dissipation to high temperatures for localized CNT growth. Other substrate areas than the microstructures remain at low temperatures, preventing the devices on the substrate from being destroyed by high temperatures. The synthesizing parameters and the influences on CNT morphology and structures are systematically investigated and optimized, and solutions for uniform temperature distribution are proposed. Upon optimization, uniform, localized, and rapid growth of CNT synthesis has been achieved on suspended microstructures, and aligned CNTs with length and uniformity comparable to conventional hot-wall CVD have been successfully obtained. The experimental results show LCVD is a promising technology for in situ and localized synthesis of CNT films on suspended microstructures for CNT-CMOS (complementary metal oxide semiconductor) integration.