Chemical Vapor Deposition

Chemical Vapor Deposition (CVD) is a method of epitaxially depositing films of solid materials on the surface of a substrate during the vapor phase of a controlled chemical reaction. CVD, also called thin-film deposition, is used prevalently for electronics, optoelectronics, catalysis, and energy applications, such as semiconductors, silicon wafer preparation, and printable solar cells.  

The CVD technique is a versatile and quick method to support film growth, enabling the generation of pure coatings with uniform thickness and controlled porosity, even on complicated or contoured surfaces. In addition, large-area and selective CVD is possible on patterned substrates. CVD provides a scalable, controllable, and cost-effective growth method for the bottom-up synthesis of two-dimensional (2D) materials or thin films such as metals (e.g., silicon, tungsten), carbon (e.g., graphene, diamond), arsenides, carbides, nitrides, oxides, and transition metal dichalcogenides (TMDCs). To synthesize well-ordered thin films, high-purity metal precursors (organometallics, halides, alkyls, alkoxides, and ketonates) are required.

CVD technology plays a key role in several fields due to its flexibility and efficiency in the preparation of different materials and thin films.

Thin film deposition: CVD is used to deposit a variety of thin films such as amorphous silicon, polycrystalline silicon, silicon nitride (Si3N4) and silicon dioxide (SiO2).

LEDs and lasers: CVD is used to manufacture III-V semiconductor materials in LEDs and lasers, such as gallium nitride (GaN) and gallium arsenide (GaAs).

Photovoltaic Cells: CVD is used to deposit thin films, such as silicon films and zinc oxide (ZnO), in the manufacture of solar cells to improve photovoltaic conversion efficiency.

Wear-resistant coatings: CVD is used to deposit super-hard coatings such as diamond and cubic boron nitride (c-BN) to improve the wear resistance and service life of tools, molds and mechanical parts.

Anti-corrosion coatings: CVD enables the deposition of corrosion-resistant coatings such as titanium nitride (TiN) and titanium carbide (TiC), which are used to protect metal surfaces from corrosion.

Anti-Reflective Coatings: CVD is used to prepare anti-reflective coatings to reduce reflections on the surface of optical elements and improve optical performance.

Filters and Waveguides: In optical communications, CVD is used to fabricate devices such as filters and optical waveguides to improve signal transmission efficiency.

Biocompatible Coatings: CVD technology is used to deposit biocompatible coatings, such as titanium nitride and zirconium oxide (ZrO2), on the surface of medical devices and implants to improve biocompatibility and durability.

Micro-Electro-Mechanical Systems (MEMS): CVD is used to fabricate structural materials and functional films in MEMS devices, such as polysilicon and silicon nitride.