Semiconductor Equipment Parts Cleaning

Cleaning semiconductor equipment parts lies in one thing ——how to ensure absolute pollution control without damaging the critical size of the parts themselves. For those delicate cavity components in high-density plasma processes such as CVD, PVD and etching , we must use chemical etching formulas for specific materials and advanced physical means such as ultrasound and CO2 snowflake cleaning in dust-free purification rooms that meet the standards of level 100 or level 100 for precision treatment. This refined cleaning method can accurately strip away specific process residues such as fluoropolymers, oxides or metals, protect fragile substrates such as quartz, ceramics and anodized aluminum, eliminate trace metal pollution, allow particulate matter counts to approach zero, and prevent premature aging and wear of components, thereby extending the average time between two cleaning operations Take the productivity of your equipment to its fullest potential.

The Pollution Control And Dimensional Accuracy

In current advanced processes below 10 nanometers, a micron-sized particle can directly act as a “fatal defect” on the wafer, causing the electrical performance of the entire wafer to be scrapped and the packaging yield to plummet. During the continuous sheet running process of the machine table, layers of complex by-products, polymers and metal residues will inevitably accumulate on the inner wall of the process cavity, the surface of components such as the spray head, etc. If this dirt accumulates to a certain extent, it will peel off under the action of thermal stress in the cavity and become flying dust particles that hit the wafer.

Whether they are precision cavity structures, gas distribution components or base support structures, they all rely on micron-level dimensional accuracy to maintain the stable limitation of plasma, the uniformity of gas flow and heat transfer.

If too aggressive or not subjected to a precision-calibrated cleaning process is used, it is very likely to bite the base material of the component, causing the sealing edge to become rounded and the surface roughness to change. This directly changes the chemical environment inside the cavity, causing premature air leakage and leading to the entire process getting out of control.

How To Protect Fragile Substrates

To avoid damaging the part substrate, the cleaning solution must be tailored to the physical and chemical properties of the material.

Quartz parts are common in high-temperature diffusion and CVD processes, but this thing is extremely sensitive to surface micro-scratches and chemical micro-cracks. When washing quartz pieces, we must use a highly formulated high-purity, low-concentration acid formula specifically designed to dissolve the oxides and metal impurities attached to them. Excessive etching must definitely be avoided during the cleaning process, otherwise the quartz surface will be atomized, the light transmittance will change, and even its overall structural strength will be weakened.

Ceramic parts in etching equipment are bombarded daily by highly corrosive plasma and high-power radio frequency. Especially ceramics with special coatings such as yttrium oxide on their surface, the grain boundary structure is very complex. If the wrong chemical cleaning agent is used, it is easy to occur intergranular corrosion, which will weaken the matrix structure of the ceramic and cause ceramic particles to continuously fall down when the parts are re-installed into the machine running plate. Ceramic parts must rely on specially made non-destructive chemical formulas, only stripping away polymer and fluoride residues, and never damaging the grain boundaries of the ceramic.

Metal alloy parts, especially anodized aluminum, are extremely demanding on the pH value of the cleaning fluid. Strong acid or base cleaning agents can instantly peel off that thin anodized layer, causing the metal substrate to be directly exposed to corrosive gases. Precision cleaning must use special lotions with mild properties and balanced pH values to ensure that the anodized barrier is intact. In addition, when the anodized layer degrades due to natural wear of the machine, qualified cleaning plants must also have the ability to peel and re-anodize without damage, help customers replace the protective cover on the metal surface, and prevent metal from outgassing .

The Cleaning In Physics And Chemistry

It is often not effective to completely eliminate those stubborn process residues with just one trick. The usual industry practice is to combine controlled chemical etching with non-destructive physical agitation to create a combination of punches.Controllable chemical etching and stripping.Chemical cleaning mainly uses targeted acids, solvents or neutral surfactants to perform specific soiling “directional blasting”:

Fluoropolymers and organic matter: Use a special solvent-based formula to only break the molecular chains of organic matter and dissolve it, while ensuring that no reaction occurs on metal or ceramic substrates.

Metal and oxide residues: Use controlled pickling tanks with very low concentrations to strip metal micropollutants through chemical reactions. In this process, the temperature and reaction time must be stuck within a safe range to prevent acid from penetrating deep into the part substrate.

Advanced physical cleaning methods

After chemical pretreatment loosens and softens the dirt, physical means are needed to completely shock down these impurities:

Ultrasonic and megabonic cleaning: Using high-frequency sound waves to create hundreds of millions of microscopic cavitation bubbles in the cleaning fluid. When these bubbles burst on the surface of the component, they will generate local micro-shock waves, which will shake out submicron particles hidden in blind holes, threaded holes and complex geometric dead corners.

CO2 Snowflake Cleaning: This is a completely dry and non-abrasive physical cleaning trick. High-pressure gas is used to spray tiny dry ice particles onto the surface of the part. The moment dry ice hits dirt, it quickly sublimates from the solid