Evaporation
【What is Evaporation?】
- Evaporation Theory
Evaporation is a widely used method in physical vapor deposition (PVD), in which solid materials are physically transformed into vapor and deposited onto a substrate to form a thin film. Materials such as metals, oxides, or fluorides are heated under vacuum until they melt or vaporize, converting into gaseous atoms or molecules.
The vacuum chamber is evacuated to a high vacuum level (approximately 10⁻³ to 10⁻⁴ Pa). Once the source material attains sufficient kinetic energy through heating, it condenses onto the substrate surface, forming a uniform thin film.
- Evaporation Features
- Higher Deposition Rate and Material Utilization Efficiency: Compared to reactive magnetron sputtering, evaporation achieves higher coating rates and material utilization, effectively reducing overall process costs.
- Simple Process with Lower Equipment Cost: The equipment design is relatively straightforward, making both initial investment and maintenance more economical.
- Easy and Stable Film Thickness Control: Thickness can be precisely monitored using quartz crystal monitoring and in-situ optical systems, ensuring consistent and repeatable results.
- Versatile Material Deposition: Capable of depositing a wide range of materials including metals (Al, Ti, Au) and oxides (AI2O3, SiO2, Ta2O5).
- Broad Application Scope: Widely used in optical coatings (e.g., anti-reflective films), electronic components (e.g., conductive and light-shielding layers), and functional packaging materials (e.g., films for food shelf-life extension).