High quality thin films with excellent chemical and structural purity, uniformity, and conformality can be manufactured using the ALD method, which involves gas-solid chemical adsorption reactions over the surface. These reactions are self-controlled and self-limiting, resulting in film growth by consecutive atomic layers.
A wide choice of materials can be deposited, including oxides, nitrides, fluorides, sulphides, pure metals (even noble ones), polymers, and graded, mixed or doped layers. Various multi-layered nanolaminates can be deposited with the option of customizing the properties of the individual layers on the molecular level.
The ALD technique not only coats silicon wafers but also 3D objects, powder, porous, and high aspect ratio (HAR) samples. Since the film grows by sequential atomic layers, chemical composition and thickness of the film can be precisely controlled. The ALD process is repeatable and various materials can be deposited at low temperatures, allowing use of also sensitive substrates such as plastics or papers.