Thermal conductivity of carbon nanotubes from a theoretical perspective for the replication of nano-transistors (based on a PhD in Nanoelectronics)  (Ph.D. Research)

Author and Researcher: Engineer Afshin Rashid

Note: For the propagation and evolution of nano-transistors, the existence of high thermal conductivity for single thermal nanotubes has been shown in theory. The results of in vitro experiments also indicate this  feature in bulk samples of single-walled carbon nanotubes as well as for single-walled nanotubes. 

The thermal conductivity of single carbon nanotubes has been measured by computational methods. One group consisted of single-walled carbon nanotubes that were massively interconnected  and the thermal conductivity of their assemblage obtained. One group also had multi-walled carbon nanotubes that were separated  The thermal conductivity of these nanotubes was investigated separately. The thermal conductivity values ​​exceeded 011 mK / W  for single-walled carbon nanotube masses. Also, the thermal conductivity value of multi- walled carbon nanotubes  is individually available above 300 mK / W

Since the structure of carbon nanotubes has different values ​​for the production and propagation of nano-transistors at different temperatures, it is shown as a function  of temperature and in the form of T (λ). The value (T (λ reaches a maximum value of 111,3 mK / W near 011 K) is seen as a peak in the graph (and then decreases with increasing temperature  . The maximum value is T). (λ that has been observed in the study, on a sample of nanotubes specific heat at  temperature of 010 K is measured. this equates to 00111 mk / W is. so value R) T (λ carbon nanotubes at its peak with the highest  value) T (λ that has been measured, comparable. According to the chart provided, even at room temperature thermal conductivity of nanotubes Carbon is very high and is 0011 mK / W, 

In the methods of propagation and evolution of nano-transistors and nanotubes 

In nanocrystals and nanotubes propagation methods with the synthesis of carbon nanotubes based on catalytic chemical vapor deposition (CCVD) involves the decomposition of the carbon source on metal particles or small metal clusters  as catalysts. Be it. The metals used for these reactions are intermediate metals  , such as iron, cobalt, nickel. Compared to arc discharge and laser abrasion, carbon nanotubes generally form at a lower temperature 

of  about 011 to 0111 degrees. 

This method is generally more selective for the production of multi-walled carbon nanotubes. Both  homogeneous and heterogeneous processes are highly sensitive to the nature and structure of the catalyst used in addition to the operating conditions. The carbon nanotubes produced  by this method are more defective than the arc method of length (several tens to hundreds of micrometers). Most of the nanotube defects are due to the use of lower temperatures than the arc method, which does not allow any structural rearrangement.

Author: Engineer Afshin Rashid 

PhD student in Nano-Microelectronics at Islamic Azad University, Science and Research Branch, Tehran