Chemical vapor deposition (CVD) is a widely used technique in materials science and engineering for the creation of thin films or coatings on substrates. In CVD, a chemical reaction takes place at or near the surface of a substrate, leading to the deposition of a thin layer of material. This process is usually carried out under controlled conditions of temperature, pressure, and gas flow rates. CVD can be used to deposit a wide range of materials, including metals, semiconductors, ceramics, and polymers. It is widely used in industries such as microelectronics, optics, and coatings for applications ranging from semiconductor device fabrication to the production of protective coatings on cutting tools. There are different variations of CVD techniques, such as atmospheric pressure CVD (APCVD), low-pressure CVD (LPCVD), and plasma-enhanced CVD (PECVD), each with its own advantages and limitations. Overall, CVD is a versatile and flexible technique that is essential for the development of advanced materials and functional coatings in various fields of technology.