PVD Systems

PVD System Design

A PVD sputtering system consists of:

• Target assembly: A disk of source material (TaN, Ta, Cu, Ti, etc.) backed by a magnetron assembly with permanent magnets. The target is water-cooled to prevent melting.
• Magnetron: Magnets behind the target create a magnetic field that confines the plasma near the target surface, increasing ionization efficiency and sputter rate.
• Process kit: Shields and collimators that contain the sputtered material and prevent chamber contamination.
• Wafer chuck: May include RF bias to accelerate ions toward the wafer for better step coverage.

Advanced PVD techniques:

• Ionized PVD (iPVD): An additional RF coil ionizes the sputtered atoms after they leave the target. Ionized atoms can be directed by wafer bias for excellent bottom coverage in high-aspect-ratio features.
• Long-throw PVD: Increased target-to-wafer distance improves directionality through collimation.