atomlagdeponering

Atomlagdeponering, often translated as atomic layer deposition (ALD), is a thin-film deposition technique. It is a subset of chemical vapor deposition (CVD) that allows for the precise control of film thickness at the atomic level. ALD relies on sequential, self-limiting surface reactions. Each cycle of the deposition process involves the introduction of a precursor gas, which chemisorbs onto the substrate surface. This chemisorption is self-limiting, meaning it only occurs until all available surface sites are occupied. Following a purging step to remove excess precursor and byproducts, a second precursor gas is introduced. This second precursor reacts with the chemisorbed species from the first precursor, forming a new layer of the desired material. A subsequent purge step completes the cycle. By repeating these cycles, films can be grown with angstrom-level precision and excellent conformality, even on complex three-dimensional structures. This precise control makes ALD valuable in applications requiring ultra-thin, uniform coatings, such as in the semiconductor industry for gate dielectrics and barrier layers, in optics for anti-reflective coatings, and in catalysis. The process is typically carried out at elevated temperatures, though low-temperature ALD variants exist.