Can the residue on the wafer surface be cleaned with plasma cleaning equipment?

Why remove photoresist? As is well known, photoresist is the core material for semiconductor wafer manufacturing. In the wafer manufacturing process, photolithography accounts for about half of the entire wafer manufacturing cost and takes up one-fifth of the entire wafer process. It is the most core process in semiconductor manufacturing, and an indispensable step in the photolithography process is wafer photoresist removal. After completing the pattern replication and transfer, the remaining photoresist on the wafer surface needs to be completely removed through the photoresist removal process. Plasma cleaning equipment can use high-frequency electric fields to generate plasma, clean wafer surfaces, improve adhesion, improve wettability, and remove pollutants and residues. Plasma cleaning is the process of removing contaminants and residues from the surface of wafers through the action of plasma. Plasma is a high-energy ion with strong chemical reactivity and mechanical forces. When plasma comes into contact with the wafer surface, chemical reactions and physical interactions occur to remove surface contaminants and residues.

The working principle of plasma cleaning equipment is that in a vacuum state, the pressure in the processing chamber will become smaller and the intermolecular distance will increase, resulting in a decrease in the mutual force between molecules. In this case, the high-voltage alternating electric field generated by a high-frequency power supply will oscillate process gases such as oxygen, hydrogen, argon, and carbon tetrafluoride into highly reactive or high-energy plasma, which will then react or collide with organic pollutants and micro particle pollutants to form volatile substances. Then, the working gas flow and vacuum pump will remove these volatile substances, thereby achieving the purpose of plasma surface cleaning and activation. Today, following the editor, let's get closer to the application of plasma cleaning equipment on wafer surfaces. After being treated with plasma cleaning technology, it has the following advantages:

1. Surface cleaning: In advanced packaging, after wet removal of PI or photoresist, there is still a certain amount of thin adhesive layer remaining on the surface, indicating that wet removal is not thorough. The commonly used low-temperature plasma cleaning machine is a dry cleaning method that can quickly remove residual glue and can also remove residual metals by Ar ion bombardment.

2. Improving adhesion: Plasma bombardment of the wafer surface can roughen the surface and increase its roughness. On the other hand, modifying the surface of the wafer can improve the adhesion between the substrate and the deposited film layer.

3. Improved wettability: The use of plasma treated materials increases the polar groups on the surface, enhances hydrophilicity, and reduces contact angle.

4. Improve cleaning efficiency: Plasma cleaning machines can generate plasma at low temperatures, and through the chemical and physical reactions of the plasma, remove impurities, oxides, and other substances on the wafer surface, thereby achieving the purpose of cleaning. Compared to traditional chemical cleaning methods, plasma cleaning machines can clean wafer surfaces more accurately, achieve better cleaning results, and effectively improve the production quality of semiconductor devices.

5. Improve production efficiency: Plasma cleaning machines can complete wafer cleaning in a short period of time, with fast cleaning speed, which can greatly improve production efficiency. In addition, plasma cleaning equipment can also perform batch cleaning, cleaning multiple wafers at once, thereby saving more time and labor costs.

6. Reduce cleaning costs: Compared to traditional chemical cleaning methods, plasma cleaning machines have lower cleaning costs. Plasma cleaning machines can use low-cost gases such as oxygen and nitrogen as cleaning media, and do not require a large amount of solvents and chemical reagents during the cleaning process, which can greatly reduce cleaning costs.

7. Environmental friendliness: Plasma cleaning machines do not require the use of large amounts of solvents and chemical reagents during the cleaning process, which can reduce environmental pollution. The cleaning medium of plasma cleaning machine can be recycled, which can greatly reduce the discharge of cleaning waste liquid and make it more environmentally friendly.

8. Cleaning stability: The cleaning effect of the plasma cleaning machine is stable, which can more accurately control the parameters during the cleaning process, thereby ensuring the consistency of the cleaning effect. The cleaning process of the plasma cleaning machine will not cause damage to the surface of the wafer, ensuring the quality of the wafer.

9. Wide applicability: Plasma cleaning machines have a wide range of cleaning applicability and can be used for cleaning various types of semiconductor devices. The plasma cleaning machine can also be used for cleaning other materials and has strong versatility.

In summary, the seismograph plasma cleaning machine has many advantages in wafer surface treatment, such as good cleaning effect, high efficiency, low cost, environmental protection, and strong stability. It is of great significance for improving the production quality and efficiency of semiconductor devices.