Controlling the initial phase of PECVD growth of vertically aligned carbon nanofibres on TiN

• We explore the growth of vertically aligned carbon nanofibers by plasma enhanced chemical vapor deposition, using lithographically defined Ni catalyst seeds on TiN. TiN is selected for being an electrically conducting diffusion barrier suitable for the realization of electronic devices. We show that the rate of Ni diffusion correlates to both the level of oxygen content in the TiN film and to the film resistivity. The synthesis of the nanofibers was characterized using electron microscopy with an emphasis on three growth parameters: substrate temperature, plasma power, and chamber pressure. We propose that a catalyst surface free from carbon deposits throughout the process will induce diffusion-limited growth. The growth will shift towards a supply-limited process when the balance between acetylene, as the effective carbon bearing gas, and atomic hydrogen, as the main etching agent, is skewed in favor of acetylene. This determines whether the dominating growth mode will be vertically aligned tip-type or disordered base-type, by affecting the competition between the formation of the first graphitic sheets on the catalyst surface and at the catalyst-substrate interface

Ämnesord

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Annan teknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Other Engineering and Technologies (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Nyckelord

Vertically aligned carbon nanofiber

VACNF

TiN

PECVD synthesis

Growth mechanism

Physics

Fysik

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)