Dense Plasma Focus Assisted Formation Of Carbon Nanoloops On Quartz

Dense Plasma Focus assisted formation of Carbon Nanoloops on Quartz substrate

- Savita Roy1 and M.P. Srivastava2 •1Kalindi College, University of Delhi, East Patel Nagar, New Delhi110008, INDIA. Email: [email protected] •2Department of Physics and Astrophysics, University of Delhi, Delhi110007, INDIA

Nanostructures comprise of spatially ordered features e.g •

nanowires

•

nanoclusters

•

nanotubes etc.

More recently  nanobelts  nanocones  other one-dimension hetrostructures viz. tree-like, Jelly fish like nanostructures

• nanoscale electronic devices • non-linear photonics, • magnetic data storage devices 50gb/in • gaseous sensors, • surface plasmon wave guides (using metal nanoclusters) etc.

• chemical vapour deposition • catalytic decomposition of hydrocarbons

• microwave plasma-enhanced CVD • Laser assisted-CVD • electric arc – discharge • laser evaporation • laser ablation etc.

Is to make functional nanostructures by developing cost effective techniques. Plasma-aided nanofabrication is quite promising.

 Extremely non-equilibrium

 High temperature ~ 1-2 keV  High fluence and  High density of plasma ~1025-26 m-3 similar to the fusion conditions

Arrangement of substrates

The X-ray Diffraction Pattern of Nickel Deposited With Three Focused Shots

AFM topography images of Nickel at substrate temperature of 70C

Ts= 94 C

Role of metals in nucleation for Carbon nanotubes,

 metal acts as catalyst Carbon ions get deposited around the metal  nanotubes grow vertically  Length of Carbon nanotubes is dependent on the thickness of the metal layer.

C.Bower, W.Zhu, S.Jin and O. Zhou, Appl. Phys. Lett. 77, 836 (2000).

From: C.Bower, W.Zhu, S.Jin and O. Zhou, Appl. Phys. Lett. 77, 836 (2000).

Nickel is on the top of the growing carbon envelop Metal provides the site for nucleation As the amount of deposits increases the length of tube increases  (and then under suitable temperature conditions )

After a certain length (of ~300 nm) the metal top gets oriented downward

carbon continues to grow around Consequently carbon nanoloops are formed.