Chemical vapor deposition

From ArticleWorld

Chemical vapour deposition (CVD) is a chemical process which involves the deposition of thin films on wafers of silicon by placing the wafers in a mixture of gases which react at the surface of the wafers. This process is usually carried out at medium to high temperatures in a furnace made for the purpose. This can be carried out in a CVD reactor as well where the wafers are heated without the walls of the reactor being imparted heat. In the case of ‘plasma enhanced’ CVD processes, one of the most significant forms of the technique, the need for a high temperature is eliminated by causing the reactant gases to be excited into a plasma. The volatile by-products are removed from the reaction chamber.

This process is widely popular in the semiconductor electronics industry. A good number of films can be deposited with the help of this method; polycrystalline, amorphous, carbon fibre, carbon nanotubes and silicon, just to name a few. Most significant out of the many applications is the production of artificial diamonds.

Forms of CVD

The process of CVD can be carried out in various forms. The ones widely used are listed below:

  1. Atmospheric pressure CVD.
  2. Atomic layer CVD.
  3. Aerosol assisted CVD.
  4. Metal-organic CVD (also known as MOCVD).
  5. Plasma-enhanced CVD (PECVD)