1 / 7

Chemical Vapour Deposition (CVD)

Chemical Vapour Deposition (CVD). David Xiulei Ji. Definition of typical CVD:. The vaporized precursors are introduced into a CVD reactor and adsorb onto a substance held at an elevated temperature. Either happens:. 1. Precursors decomposition (synthesis of CNT).

tom
Download Presentation

Chemical Vapour Deposition (CVD)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Chemical Vapour Deposition (CVD) David Xiulei Ji Definition of typical CVD: The vaporized precursors are introduced into a CVD reactor and adsorb onto a substance held at an elevated temperature. Either happens: 1. Precursors decomposition (synthesis of CNT) 2. Precursors reaction with other gases or vapour to form crystal (synthesis of Metal Nitride)

  2. Typical Reactor and Process: Typical Reactor: Precursors, Carrier gases CVD process: • mass transport of reactants to the growth surface • (b) chemical reactions on the growth surface • (c) removal of undesired composition in the product.

  3. Growth Mechanism: Substrate Physical Review Letters (1990) 64 1943 Different growth mode decided by Interfacial free energy terms and lattice dismatch Thin film, Nano particles and Thin film&Nano particles

  4. Conditions That Matter in CVD • Reactants flow rate and different reactants • Reaction Temperature • Pressure of the system • Reacting Time: thickness of film or length of nano stuffs • Carrier gas: Argon, H2, Water…. to achieve slow homogeneous growth • Substrate: different types (Si, SiO2, Ni, quartz etc.) differently terminated ect. • Position of substrate in terms of gas flow

  5. More CVD Methods: a) LP PECVD: low pressured plasma enhanced CVD------utilized in industry Limitations: Not good for deposition of materials in a large scale. b) AP PECVD: Atmospheric pressured plasma enhanced CVD c) MO CVD: Metal organo CVD. Organic ligands as reducing agent. d) Catalytic CVD (Ni, Co, Fe nano particles) e) Template based CVD such as employ Aluminium Membrane

  6. One Successful Case: Carbon Nanotube (CNT): Initially synthesized under arc discharge method, one of CVD method. Ref: Nature, (1990), 347, 354 (C60) Nature, (1991), 354, 56 (First CNT) Chemical Reviews, 2005, Vol. 105, No. 4 1039

  7. Thank you Want to know more? Please go to the journal named Chemical Vapour Deposition

More Related