What is Vacuum Plasma?

Vacuum plasma is a process by which a gas is ionized in a vacuum chamber to form plasma. Oxygen and argon plasmas are commonly used to clean, etch or activate a surface.

These treatments have been around since the early 1970s. It is often used as a way to clean organic impurities and contaminants from a surface. Plasma is also useful in etching electronic products such as circuit boards.

Vacuum plasma chamber
Vacuum plasma chamber on a BT-1 system.
The process is performed in a plasma chamber between 40 and 300 mTorr, depending on the desired outcome of the plasma treatment.

These treatments are commonly used in the manufacturing of electronic devices, medical devices, textiles, plastics, rubbers, and more. Almost any material can be treated in a plasma chamber.

This technology is able to create a plasma with the ability to fully permeate a product, allowing treatment of the interior and exterior surfaces in order to improve bonding, printing, painting, coating, or wettability.

Organic surface contaminants are invisible to the casual observer, but they greatly impact an object’s ability to interact with other materials.

Our plasma treatment systems are able to remove 100% of these organic contaminants. This increases the bond strength of a solder or glue, increases or decreases wettability, and ensures any type of printing, painting, or coating remains on the object's surface.

Why is a vacuum required for plasma?

Plasma is created in a vacuum for many reasons, but there are two main reasons why a vacuum is required.

The gases we introduce to the chamber won't ionize under pressure, so the vacuum must be created before the gases will ionize and the plasma is created.

Additionally, the vacuum allows us to control which gases are present in the chamber. This control is crucial to the repeatability of our plasma processes.

How long does treatment last?

Most plasma treatments last approximately 48 hours if the treated surface remains clean and dry. This time can vary depending on the treatment performed and the conditions parts are stored in.

If a longer shelf life is needed, vacuum packing immediately after cleaning will extend the shelf life.

Who uses vacuum plasma?

Plasma is used by many industries. A perfectly clean surface is imperative to allow an adhesive to bond with surfaces that are dissimilar in bondability. For instance, when bonding a rubber part to a plastic tool. Plastic and rubber would generally use different types of adhesives.

This creates a situation where the only way to use the same adhesive on both materials is to ensure that each surface is clean and activated.

Plasma activation leaves a free radical on the surface of a plastic or rubber material to allow a stronger bond between the surface of the material and the bonding agent.

These free radicals are created on the surface of the material and are chemically unstable; they attach to the bonding agent with incredible strength.

Creating these free radicals is also useful when printing on a surface that would generally not accept ink well. When printing on a shiny or glossy surface, plasma activation is required to allow the surface to accept the ink and create a smear resistant printed surface.

Plasma can be used to coat a surface to increase its lustrous properties with a process called plasma polymerization. This is particularly useful for a surface that you want to keep clean from hair and debris, such as ear buds.

Vacuum plasma is used to etch away a layer of material a few atoms thick during the manufacturing of small integrated circuit chips. Some IC chips are manufactured with only 10nm between electrical components, and there are already manufacturers with plans to bring that down to 5nm!

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