Plasma Cleaning
Specifically, we are discussing Low pressure plasma cleaning on this page.
A safe environmentally friendly process capable of removing a very wide range of contaminants from the surface of a material, without damaging the product.
Also ideal as a preparation for further processes such as painting or bonding.
Plasma Cleaning Process vs. Plasma Cleaners
It's important to distinguish between the process and the product:
- Plasma Cleaning (Process): This is the application page you are on now. It describes the scientific method of using plasma to remove contaminants from a surface. It answers the "what" and "how" of plasma cleaning.
- Plasma Cleaners (Products): These are the machines and systems that perform the plasma cleaning process. If you are looking for equipment to implement this technology, from desktop units for laboratories to large-scale industrial systems, please visit our product page.
Mastering the Science of surface cleanliness:
A Message from our founder Jörg Eisenlohr
For over 20 years, we have pushed the boundaries of plasma surface treatment.
What began as a mission to provide reliable industrial cleaning has evolved into a two-decade legacy of solving the world’s most complex adhesion and contamination challenges.
Our expertise spans the entire spectrum of plasma cleaning from the foundational removal of industrial greases and mold release agents to the ultra-clean requirements of EUV lithography.
Engineering Solutions for Extreme Environments
where 'clean' is measured at the atomic level. Our work in EUV lithography represents the pinnacle of this precision:
- Atomic-Level Purity: Reducing non-organic contamination to near-zero Atomic %.
- Volatile Analysis: Sensitive Residual Gas Analysis (RGA) by quadrupole mass spectrometry is used to ensure outgassing meets the most stringent vacuum standards.
- Thermal Management: Developing specialized protocols for complex geometries that are sensitive to overheating, ensuring part integrity is never sacrificed for cleanliness.
Reliability by Design
Whether processing bulk components, roll-to-roll substrates, or delicate sheet goods, our philosophy remains the same: Quality is a byproduct of equipment design.
We don't just provide a machine; we provide months of collaborative development, process validation, and a commitment to repeatability that only 20 years of empirical data can produce.
Oxygen (O2) Plasma Cleaning
Plasma cleaning of organic contaminants
Plasma cleaning involves the removal of organic contaminants by a reactive plasma generated in a chamber.
How does it work?
A reactive gas plasma, often called an oxygen or O₂ plasma, is created in the chamber. This plasma actively reacts with the contaminants on the surface of the material.The UV radiation generated in the plasma breaks the carbon bonds of the organic compounds. The reactive gas then combines with the dissolved impurities. These reaction products are removed from the chamber in a gaseous state, leaving the surface clean, precise and free of residue.
Typical applications
Plasma cleaning is an environmentally friendly and highly accurate method used in a variety of industries, including electronics, medical and research, for the efficient removal of organic residues.
Micro Sandblasting
Plasma cleaning of inorganic contaminants
Plasma cleaning (Micro sandblasting) is ideal for removing inorganic contaminants.
How does it work?
The high UV content of the plasma effectively breaks down carbon deposits.
At the same time, the activated gas molecules are accelerated to high speeds. These molecules act like a micro-sandblast, removing even the smallest contaminants from the product surface.
Once the optimum process conditions have been defined, extremely high levels of surface cleanliness can be achieved.
Typical applications
This process is essential in the electronics industry and other applications where the highest standards of cleanliness are required.
Advantages of Plasma cleaning
The advantages of plasma cleaning apply to both O2 and micro sandblasting.
- Environmentally friendly compared to wet cleaning.
- Cost effective. Cleaning fluids have both purchase and disposal costs.
- Constant controlled conditions.
- Small floor space footprint.
FAQ
What are the advantages of low-pressure plasma cleaning?
Compared to conventional cleaning methods.
- Simplified control and repeatability due to fewer parameters.
- The process is dry.
- No monitoring of wet chemical cleaning and washing liquids.
- Environmentally friendly. No need to dispose of wet chemical liquids.
- The cleaning medium is gaseous.
- A wide range of contaminants that can be removed.
Compared to atmospheric plasma cleaning
- The atmosphere in the chamber is constant so that recontamination can be avoided.
- The gas throughput is in the range of a few milliliters per minute. In some cases, only the ambient air can be used as the process gas.
- Due to the low pressure in the chamber, there is no risk of fire or explosion if reactive gases such as hydrogen or oxygen are used.
- The exhaust gases do not contain ozone.
- No active extraction system is required.
What happens during plasma cleaning?
There are three main mechanisms at work in the chamber: chemical cleaning, physical cleaning and incineration. In addition, the conditions in the chamber are ideal for disinfection and sterilisation. This can be achieved by selecting conditions that generate a high UV content. For more information click on: Plasma sterilisation.
Chemical plasma cleaning:
The process gas in the cleaning chamber is excited by a high-frequency generator. The resulting radicals and ionized particles react with the contamination on the surface of the product. This produces H2O and CO2.
The environment in the production area remains unaffected by the process, e.g. no ozone, as can be the case with atmospheric plasma.
Physical plasma cleaning:
The molecules of the process gas are accelerated by the high-frequency field. They collide with the product to be cleaned. The high atomic mass causes a kind of micro-sandblasting. The impurities are removed mechanically.
Combustion - The use of elevated temperatures in plasma cleaning:
Special conditions are created in the chamber of the plasma system to generate heat in the product to be cleaned. This favours the outgassing of volatile substances, which polymerize on the surface and can then be cleaned. A rarely discussed but effective process. Conversely, controlling the conditions during plasma cleaning prevents the product from heating up and discoloring. This applies in particular to conductive materials.
Combinations of chemical and physical plasma cleaning can be extremely effective. By using physical cleaning, the bonds of impurities are broken, which are then chemically removed via the gas phase. An interesting side effect is the fact that ionized particles in the plasma chamber dissipate static charges, which facilitates the removal of particles.
Which is the right plasma cleaning process for my application?
Chemical plasma cleaning:
This is often referred to as oxygen plasma cleaning, but oxygen is only one of the possible gases.
It can be problematic in that the surfaces could oxidize.
For example, it is not the best option for cleaning silver and some other metals. However, if your product is oxidation resistant, it is the gas of choice.
There are various gases that can be used in place of oxygen to remove oxidation from the surface of your product.
This cleaning method is particularly effective in removing organic contaminants (oils, hydrocarbons, etc.).
Physical plasma cleaning (sputtering - micro-sandblasting)
This method is very suitable for removing inorganic contaminants that are relatively stable in a vacuum.
For example, unwanted traces of lead or salts can be removed from dried fingerprints. This is because these cannot be chemically cleaned.
Sputtering proves to be the ideal method in such cases.
Plasma cleaning at an elevated temperature. Combustion.
Another possible application of plasma treatment is the heating of components using high frequency.
The application of heat to products in a vacuum can be slow and difficult.
This type of plasma cleaning can be very effective in removing volatile contaminants. This is especially true when the contaminants have a long and difficult path out of the product, such as in hoses or cables.
Instead of heating overnight, the heat can be applied almost immediately and precisely controlled
It is possible to melt copper in a vacuum within a short time using plasma.
How clean will my parts be after plasma cleaning?
Let's ask a counter question here - how clean do they need to be? From applications to improve or replace ultrasonic cleaners to applications for the electronics industry.
Here, contamination is measured by counting atoms and is so small that it pushes the limits of the technology to determine the atomic amount of contamination on a surface. So literally sparkling clean.
Can all materials be cleaned with the plasma?
No. First of all, they have to withstand the vacuum.
Materials that have a high level of volatile components such as water bound to them are very difficult or even impossible to clean.
Closed-cell foams can be damaged in a vacuum.
However, the list of materials that can be cleaned is long and ranges from plastics, glass and metals to ceramics. Please contact us for further details.
How do the shape and dimensions affect the plasma treatment?
Mostly hardly at all. We have cleaned everything from fine powders and even tiny diamonds to large components and rolls of material and have found no adverse effects. Our large chambers with a volume of 8000 litres provide sufficient space, and our modular plasma generators ensure that the power is distributed evenly throughout the system. The plasma cleans even the smallest cracks and cavities.
How do I know if plasma cleaning is right for my products?
Our service team will be happy to answer any questions you may have. Please contact us.
We will assist you in any way we can to answer your questions.
This takes the form of advice on whether low-pressure plasma cleaning is suitable and, if so, which system is best suited to your needs. It is also possible to carry out tests for you. In more complex cases, we take over the process development.
Until you make your decision, you have the option of contract processing at our premises as well as hiring equipment for trials or initial production. Rental plasma systems
Special conditions with rental price offsetting for system purchases are possible. Get in touch with us to discuss your needs or concerns, or simply give us a call. Arrange an appointment for a trial treatment.