Low pressure plasma cleaning is similar to plasma etching process, both of which use active particles generated by plasma to react with the material surface and remove substances from the material surface. However, the ion energy required for plasma cleaning technology is lower than that of plasma etching process. The material removed by plasma etching process is solid material (such as silicon-based material, etc.), which utilizes chemical reactions with ion bombardment synergy to effectively enhance the etching reaction rate using charged ions, known as reactive ion etching. However, the plasma cleaning process requires controlling the effect of ion bombardment to prevent excessive ion bombardment energy from damaging the material surface.

The difference between plasma cleaning and plasma etching

Below, we will explain the plasma cleaning 

principle diagram in Figure 1 and the plasma etching principle diagram in Figure 2 to help better understand the difference between plasma cleaning and plasma etching.

Figure 1 Principle of plasma cleaning

Figure 2 Plasma Etching Principle

From Figure 1, it can be seen that plasma cleaning is mainly used to remove excess pollutants on the surface of materials, without affecting the materials themselves. Through plasma cleaning, the dirt adsorbed on the surface of the material has been effectively removed.

From Figure 2, it can be seen that plasma etching is mainly used to remove the substrate material and obtain the desired shape. The principle of plasma etching is to selectively remove materials from the substrate surface through reactive plasma gas, making it a selective etching method.

The main differences between plasma cleaning and plasma etching processes are as follows:

Objective

Plasma cleaning: The main purpose is to remove pollutants on the surface of objects, such as organic matter, oxides, oil stains, particles, etc., in order to improve the cleanliness and activity of the surface, and provide good surface conditions for subsequent bonding, welding, coating, photolithography and other processes. For example, in the manufacturing of electronic components, cleaning impurities on the surface of chips ensures good connections during chip packaging.

Plasma etching: used to selectively remove materials to form specific patterns or structures. In the fields of semiconductor manufacturing, microelectromechanical systems (MEMS) manufacturing, etc., it is used to etch complex circuit patterns, microchannels, microstructures, etc. on wafers or other materials. For example, when manufacturing integrated circuits, structures such as transistors and wiring are etched onto silicon wafers.

The impact on materials

Plasma cleaning: only affects the surface by a few nanometers, without altering the overall properties of the material. The damage to the surface of the material is relatively small, mainly by removing surface pollutants. Generally, it does not change the structure and properties of the material itself, but only improves the cleanliness and activity of the surface.

Plasma etching: It can significantly alter the surface morphology and structure of materials. The microstructure and properties of materials may have a significant impact, such as changing the surface morphology, roughness, electrical properties, etc. During the etching process, precise control of process parameters is required to ensure that the etching accuracy and impact on material properties are within the design requirements.

Gas selection

Plasma cleaning: commonly used oxygen, argon, hydrogen, etc., mainly for cleaning and modification purposes.

Plasma etching: using fluorine based, chlorine based and other gases to etch different materials.

The above is the main introduction about the difference between plasma cleaning and plasma etching. Both plasma cleaning and plasma etching are applications of low-temperature plasma technology in material surface treatment. The main difference is that one is to remove the unnecessary parts of the material itself, and the other is to remove the contaminated parts attached to the surface of the material.