Print Email Facebook Twitter Closed-loop control of laser assisted chemical vapor deposition growth of carbon nanotubes Title Closed-loop control of laser assisted chemical vapor deposition growth of carbon nanotubes Author van de Burgt, Y. Bellouard, Y. Mandamparambil, R. Haluska, M. Dietzel, A.H. Publication year 2012 Abstract Laser-assisted chemical vapor deposition growth is an attractive mask-less process for growing locally aligned nanotubes in selected places on temperature sensitive substrates. An essential parameter for a successful and reproducible synthesis of nanotubes is the temperature during growth. Here, we demonstrate a temperature feedback control mechanism based on the dynamic, in situ monitoring of the infrared radiation coupled with reflectivity information. With the information provided by these sensors, an infrared laser, focused on a silicon substrate covered with aluminum-oxide and iron catalyst layers, can be controlled. The growth takes place in a gaseous mixture of argon (carrier gas), hydrogen (process gas), and ethylene (carbon-containing gas). Scanning electron microscopy and Raman spectroscopy analysis demonstrate the excellent reproducibility of the closed-loop control process over multiple experiments. Furthermore, we developed a unique method to identify the onset for catalyst formation and activation by monitoring the fluctuation of the reflected laser beam. © 2012 American Institute of Physics. Subject Mechatronics, Mechanics & MaterialsHOL - HolstTS - Technical SciencesChemistryIndustrial Innovation To reference this document use: http://resolver.tudelft.nl/uuid:bf87d2cc-ac52-4979-b356-a9eda27f1d82 TNO identifier 463742 ISSN 0021-8979 Source Journal of Applied Physics, 112 (3) Article number No.: 034904 Document type article Files To receive the publication files, please send an e-mail request to TNO Library.