The purpose of this research is to examine the effect of iron catalyst thickness on the straightness of growth of carbon nanotube microelectromechanical systems (CNT-MEMS). One of the key benefits of CNT-MEMS is that they can potentially have very high aspect ratios. One of the challenges in attaining these high aspect ratios is maintaining device straightness; as these devices get taller, the edges tend to curve rather than grow straight vertically. Scanning electron mi- croscope images of samples grown using various iron catalyst thicknesses show that both straight growth and relatively good edge definition can be achieved using iron thicknesses between 7 and 8 nm. Below this thickness, individual CNT are well-aligned, but CNT forests are not necessarily straight. Above this thickness, the CNT forests are relatively straight, but individual CNT are not well-aligned and edge definition is very poor. Iron availability for CNT growth is also affected by a device's or feature's proximity to other regions of iron. By using an iron catalyst thickness ap- propriate for straight growth, and by adding borders of iron around features or devices, a designer can greatly improve straightness of growth for CNT-MEMS.
College and Department
Ira A. Fulton College of Engineering and Technology; Mechanical Engineering
BYU ScholarsArchive Citation
Moulton, Kellen S., "Straightness of Growth for Carbon Nanotube Microelectromechanical Systems" (2010). All Theses and Dissertations. 2413.
microelectromechanical systems, carbon nanotubes, iron catalyst thickness, Kellen Moulton