Atomic Layer Deposition Methods
Atomic Layer Deposition (ALD) is a thin-film deposition technique used in various industries such as semiconductor manufacturing, solar cells, and coatings. It is a precise and controlled method that allows for the uniform deposition of materials at the atomic level. ALD is based on a sequential, self-limiting surface chemical reaction process that enables precise control over film thickness and composition.
There are two main ALD methods commonly used in the industry:
1. Sequential ALD: This method involves the alternate exposure of the substrate to two precursors. The first precursor reacts with the substrate surface in a self-limiting manner, forming a monolayer of material. Excess precursor is then removed before the second precursor is introduced. This process continues in a cycle until the desired film thickness is achieved.
2. Plasma-Enhanced ALD (PEALD): In this method, one or both precursors are activated by a plasma source before they are introduced to the substrate. Plasma activation increases the reactivity of the precursors, allowing for lower process temperatures and improved film quality.
Both methods offer unique advantages and are chosen based on the specific requirements of the application. ALD is known for its excellent conformality, thickness control, and the ability to deposit a wide range of materials including oxides, nitrides, and metals.
Overall, Atomic Layer Deposition methods play a crucial role in the fabrication of advanced thin films with precise control over properties, making them essential for the development of cutting-edge electronic devices and materials in a variety of industries.