Plasma cleaning equipment can adopt different cleaning methods according to the type of pollutants
Plasma cleaning is a technology that removes contaminants from the molecular layer (generally 3~30nm in thickness) through chemical and physical action, and improves the surface activity of the workpiece. The pollutants removed may be organic matter, epoxy resin, photoresist, oxide, particulate pollutants, etc. Plasma treatment can adopt different cleaning methods according to the type of pollutants.
1. Ashing surface organic layer
Pollutants evaporate under vacuum and instantaneous high temperature, crushed by high-energy ions, and discharged from the vacuum.
UV radiation destroys pollutants, and plasma treatment can only penetrate a few nanometers per second, so the pollution layer is not thick. Fingerprints are also applicable.
2. Oxide removal
This process involves the use of hydrogen or a mixture of hydrogen and argon. Sometimes a two-step method can also be used. The surface is first oxidized for 5 minutes, and then a mixture of hydrogen and argon is used to remove the oxidation. Various gases can also be processed at the same time.
3. Welding
In general, chemicals should be used before soldering printed circuit boards. These chemicals must be removed by plasma after welding, otherwise it will cause corrosion and other problems.
The principle of plasma cleaning equipment is: under vacuum, the pressure decreases, the distance between molecules increases, and the force between molecules decreases. The high-pressure alternating electric field generated by the radio frequency source is used to flush technical gases such as oxygen, argon, hydrogen, etc. The ions with high reactivity and high energy react or collide with organic pollutants and particulate pollutants to form volatile substances. The working airflow and vacuum pump remove the volatile substances to achieve surface cleaning and activation. It is a thorough stripping cleaning method, which has the advantages of no waste liquid, metals, semiconductors, oxides and most polymer materials after cleaning, and the advantages of overall, partial and complex structure cleaning.
Plasma cleaning is to treat the surface of the workpiece through chemical or physical action to achieve the removal of contaminants at the molecular level (generally with a thickness of 3-30nm), thereby improving the surface activity of the workpiece. The pollutants removed may be organic matter, epoxy resin, photoresist, oxide, microparticle pollutants, etc. Corresponding to different pollutants, different cleaning processes should be used. In this case, plasma treatment can produce the following effects:
1. Ashing surface organic layer
Part of the pollutants evaporate under vacuum and instantaneous high temperature, and the pollutants are crushed by high-energy ions and taken away by the vacuum.
Ultraviolet radiation destroys pollutants. Since plasma treatment can only penetrate a few nanometers per second, the pollutant layer should not be too thick. Fingerprints are also applicable.
2. Oxide removal
This treatment involves the use of hydrogen or a mixture of hydrogen and argon. Sometimes a two-step process is also used. The first step is to oxidize the surface with oxygen for 5 minutes, and the second step is to remove the oxide layer with a mixture of hydrogen and argon. It can also be treated with several gases at the same time.
3. Welding
Generally, printed circuit boards should be treated with chemicals before soldering. After welding, these chemicals must be removed by plasma, otherwise it will cause corrosion and other problems.
The principle of plasma cleaning equipment is that in a vacuum state, the pressure is getting smaller and smaller, the distance between molecules is getting larger, and the force between molecules is getting smaller and smaller. The high-voltage alternating electric field generated by the radio frequency source is used to process oxygen, argon, hydrogen, etc. The gas oscillates into ions with high reactivity or high energy, and then reacts or collides with organic pollutants and micro-particle pollutants to form volatile substances, and then these volatile substances are removed by the working gas stream and vacuum pump to achieve surface cleaning The purpose of activation. It is a thorough peeling cleaning in the cleaning method. Its advantage is that there is no waste liquid after cleaning. It is characterized by good treatment of metals, semiconductors, oxides and most polymer materials, and can achieve overall and partial and complex structures. Of cleaning.