CVD (Chemical Vapor Deposition) is a process in which the substrate is exposed to one or more volatile precursors, reacting and decomposing on the substrate surface to create the desired thin film deposit. This method is often used to fabricate high quality, high performance, solid material in vacuum environment. Therefore, this process commonly used in the semiconductor industry to fabricate thin films.

 Figure 1: Steps involved in Chemical Vapor Deposition

In typical CVD, precursor gases (often diluted in carrier gas) are fed into the reaction chamber at ambient temperature. When they pass or come in contact with the heated substrate, they react or decompose to form a solid phase and are deposited on the substrate. During this process, volatile by-products are also produced, which are removed by gas flow through the reaction chamber. The substrate temperature is very important and can affect the reactions that will take place.                                                                                                                                                       

  Figure 2: Schematic diagram - The steps involved in chemical vapor deposition