Metaalfilm

Metaalfilm, or metal film, refers to a thin layer of metal deposited on a substrate to modify surface properties. Thickness typically ranges from a few nanometers to several micrometers. Metal films are used to achieve electrical conduction, optical reflectivity, corrosion protection, or catalytic activity, depending on the choice of metal and deposition conditions.

Production methods include physical vapor deposition (PVD) such as evaporation and sputtering; chemical vapor deposition (CVD); electroplating; and atomic layer deposition (ALD). Each method offers different control over thickness, conformity, and microstructure. The choice depends on substrate material, required film properties, and cost. Film quality is influenced by parameters such as temperature, vacuum level, and deposition rate.

Common metals used for films include copper, aluminum, gold, silver, nickel, chromium, platinum, and titanium. Film properties depend on thickness, crystallinity, grain size, and residual stress. They can be polycrystalline or epitaxial, and may include diffusion barriers, adhesion layers, or multilayer stacks to tailor performance.

Applications span electronics (interconnects, contacts, and vias), optics (reflective coatings, mirrors, and plasmonic structures), protective barriers and corrosion-resistant coatings, sensors, catalytic surfaces, and solar cells. In microfabrication, metal films serve as electrodes, masks, or contact pads.

Challenges include adhesion to the substrate, diffusion at interfaces, stress-induced cracking, and aging due to oxidation or electromigration. Film thickness uniformity and contamination are critical. Characterization techniques include X-ray diffraction for crystallography, scanning electron microscopy and transmission electron microscopy for morphology, ellipsometry for thickness, and resistivity measurements for electrical performance.