There are two important wet processes that play an important role in wafer production – they are called wafer cleaning and reclaim. These industry processes are popular for they give a huge benefit particularly to the semiconductor industry. In this resource, I am going to discuss both processes – one by one.
Wafer cleaning – in a nutshell
Wafer cleaning has long been recognized as an important industry process. It involves the removal of particulate and chemical impurities from the semiconductor surface without producing any damage to the substrate. This process is made particularly for silicon-based material as this is the most common and important element utilized for the fabrication of integrated circuits (ICs). Wafer cleaning procedure usually is based on wet-chemical processes where hydrogen peroxide solutions is used.
Some advantages and benefits of wafer cleaning:
- Offers effective removal of all types of surface contaminants, organic and metallic matters
- Relatively safe, process is simple, and economical for production application
- Implementable by a variety of techniques
- Provides no etch or damage to silicon
- Enhances the performance of the semiconductor products
- Environment friendly since it uses contamination-free and volatilizable chemicals.
What is wafer reclaim?
In simple terms, wafer reclaim includes the process of transforming a used wafer to its brand new look at a lower cost. This is definitely a cost-effective alternative to buying new wafers. This process involves a number of steps, which include: (1) sort – the procedure that is critical to prevent metallic contamination (2) strip – this is performed through wet immersion using batch tanks such as Orca; (3) Lapping and grinding – required for thick SOI (4) polish – using chemical and mechanical polishing, which can remove residual slurry and unwanted particles from the substrate, and metallic contaminants; (5) cleaning – which is performed in batch immersion tanks and (6) Inspection – the step that sorts again the thickness and defect level before being returned for use in the fab.
Some benefits of wafer reclaim
- Significantly cuts production costs of manufacturing brand new wafers.
- Offers environmental benefits; waste materials from the production of new wafers are essentially reduced by this alternative.
- It helps extend the life of wafers – longer span of time for use
Again, wafer cleaning and wafer reclaim give a huge benefit to the semiconductor industry particularly when it comes to cutting the production costs while the product usability is not compromised. Therefore, it just makes sense to make use of these technologies.