Argon plasma cleaning is an inert, non-reactive process. This approach mainly uses physical action to clean surfaces.
On the other hand, Oxygen plasma cleaning is reactive since it introduces oxygen atoms. These atoms chemically alter and clean the surface. They also often improve adhesion.
Argon Plasma Cleaning: Pros and Cons
plasmaetch.com, What is Argon Plasma?
Pros
- Inert nature: Argon plasma is inert, meaning it does not chemically react with the surface. This makes it ideal for cleaning sensitive. These typically cannot handle chemical alterations. Argon ions bombard the surface, physically removing contaminants.
- Surface hardening: Argon plasma can harden surfaces at low energy levels. This is possible through ionic bombardment. The process does not alter the chemical structure. However, it can slightly change surface roughness.
- Controlled etching: Argon plasma can etch or roughen a surface. Thus this plasma treatment can improve a surface’s texture on a microscopic scale (nanometers).
researchgate.net, Graphical schematization of the Ar plasma cleaning treatment
Cons
- Limited chemical cleaning: Since argon is inert, it is ineffective at breaking down organic contaminants. Examples are oils or carbon-based residues.
- Surface morphology alteration: Argon plasma can effectively clean surfaces. However, its physical bombardment may slightly alter the material’s structure.
Oxygen Plasma Cleaning: Pros and Cons
Henniker Plasma Treatment, Henniker Plasma – Plasma Cleaning Explained, 2021
Pros
- Effective organic contaminant removal: Oxygen plasma cleaning excels at removing organic materials. Typically these are oils, carbon residues, and other contaminants. The oxygen ions chemically react with these impurities. By so doing, they break them down for easier removal.
- Chemical surface modification: In addition to cleaning, oxygen plasma can chemically modify a surface. The oxygen plasma cleaning machine introduces oxygen-containing groups such as hydroxyl (-OH) or carboxyl (-COOH) groups.
This feature improves the material’s wettability and adhesion. The latter is critical for processes like bonding, coating, or printing.
- Improved adhesion: Surfaces treated with oxygen plasma often have higher surface energy. One outcome is that it makes them better for adhesion in applications such as wire bonding, coating, or printing.
Cons
- Risk of oxidation: Oxygen is highly reactive. Thus, some materials may experience unwanted oxidation.
- More complex setup: Oxygen plasma systems may require careful control to avoid over-modification or damage.
Comparison of Applicable Scenarios
When choosing between argon plasma cleaning and oxygen plasma cleaning, it’s important to consider the material and purpose.
For surface cleaning without chemical reactions, argon plasma cleaning is ideal. It provides physical cleaning, mild etching, and surface hardening. Argon plasma cleaner does these without altering the material chemically.
For example, in cases where fibers, glass, or metals need to maintain their original chemical structure, argon plasma is the safer choice. Oxygen plasma introduces oxygen-containing groups. These groups improve adhesion on materials that need to bond with coatings, adhesives, or inks.
The oxygen plasma process is especially useful for plastics and metals. It is also beneficial for surfaces that will undergo further processing. Examples include medical devices or packaging industries.
Conclusion
Argon and oxygen plasma cleaning both have unique benefits. However, the choice depends on the application. Argon plasma cleaning is best for applications where the surface must be cleaned gently. In such a situation, chemical reactions are unnecessary.
On the flip side, oxygen plasma cleaning is suitable for deep cleaning. The plasma process is ideal for dealing with organic residues and improving surface adhesion.
With innovations in plasma technology, Keylink Technology is a key player. As a leading manufacturer in Asia, Keylink offers a wide range of plasma systems. These include atmospheric and low-pressure plasma systems for surface treatment. By providing over 2,000 pre-treatment solutions each year, Keylink continues to meet the high demands of its global customers.
References
- Comparison of Argon and Oxygen Plasma Treatments for Ambient Room-Temperature Wafer-Scale Au–Au Bonding Using Ultrathin Au Films; Michitaka Yamamoto, Takashi Matsumae, Yuichi Kurashima, Hideki Takagi, Tadatomo Suga, Toshihiro Itoh and Eiji Higurashi; 2019(https://www.mdpi.com/2072-666X/10/2/119)
- Comparison of Argon and Oxygen Plasma Treatments on LED Chip Bond Pad for Wire Bond Application; Hui Yuen Peng, Mutharasu Devarajan, Teik Toon Lee; 2014 (https://www.ijser.org/researchpaper/Comparison-of-Argon-and-Oxygen-Plasma-Treatments-on-LED-Chip.pdf)
