Exploring the Evaporation of Metal

Written by: Denton Vacuum, LLC

Summary: Metallization is a process consisting of three phases.

Metallization is an advanced manufacturing method that can alter the property of plastics, woods and other materials not normally associated with being “durable.” The process has also substantially reduced costs of products in the retail market. Vacuum metalizing something boils down to three separate processes that completely transform metals like aluminum.

Protecting the Substrate

When you want to metalize something, that “something” you’re metalizing is broadly known as the “substrate.” The metallization process transfers the properties of the metal to the substrate, but that requires superheating the metal until it breaks down into a gas. PVD coating equipment is designed with extreme temperature control in mind, such that you can super heat and super cool at precise intervals.

The substrate is essentially entering a cloud of metallic particles that are ionized, or charged with energy. The particles bounce off of one another, breaking into smaller atoms and smashing into the substrate. Sometimes, sputter deposition is used for a more precise coating. Like anodizing.

You can think of this process as three separate phases all taking place within a vacuum. The vacuum helps control temperature, which would otherwise destroy the substrate.

Aluminum is one of the most popular metals to use for this process because it adheres well to silicon dioxide, and has a low boiling point. This makes the metal ideal for vacuum deposition, but aluminum is not the only metal used. In some cases, especially when the manufacturer wishes to reduce the effects of electromigration, small amounts of copper may be added.