The goal of thin film technology is the fabrication of thin layers to control the physical properties and surfaces of chosen materials, such that they are exactly right for the desired applications.
The deposition capabilities depend strongly on the equipment.
- Coatings on planar substrates through PVD (sputtering or evaporation) or CVD (Oxidation, PECVD)
- Maximum substrate diameter: 200 mm (depending on equipment)
- Maximum substrate thickness: 2 mm (depending on equipment, thicker substrates upon request)
- Coating materials available: Metals, insulators (depending on equipment, for example: Au, Sn, Al, Si, Pt, Ti, SiO2, SixNy, SixOy, SiOxNy ...)
- Deposition temperatures: Room temperature to 400 °C (depending on equipment)
- Film thicknesses: a few nanometers to 500 nm (depending on equipment, thicker films upon request)
- Electrodes and traces
- Diffusion barriers and adhesion layers
- Sacrificial layers
- Optical coatings (filters, mirrors ...)
- Seed layers for electroplating
- Electrical insulation, passivation and surface protection
- Masking and etch-stop layers for patterning (for wet and dry etching)
- Decorative thin films
In many cases, thin films and structures fabricated from thin films accomplish significant tasks within a few nano or micrometers. The fabrication of such films is primarily done through physical (PVD) or chemical (CVD) vapor deposition.
The process parameters have a large impact on the film properties. Among the most important parameters we must take into account the substrate temperature, substrate surface condition (roughness, impurities), pressure, and deposition rate.
Film properties can be manipulated through the choice of deposition technique and, to a certain degree, through the process parameters. Film thickness, morphology, electrical conductance, refractive index, surface roughness, chemical resistance and pinhole density are among the most important thin film characteristics.
The deposition processes for thin films are carried out mostly outside of a thermodynamic equilibrium. Therefore, the properties of the thin film can vary significantly from those of the bulk material.