Because they are numerous, it would not even be possible to briefly outline all the steps that make up the effective processes of silicon wafer reclaiming or recycling. So, in this short note, just the first six or so steps being provided by silicon wafer suppliers will be mentioned.
Taken as a whole, these steps help its users achieve new cost cutting goals. Interestingly, it is the wafer recyclers and suppliers who are setting the trend with faster turnaround times all in a single day. And they have the capacity to manage thousands of wafers in a single work day as well. What makes this achievement possible is cost containments and a centralized inventory control system.
Here are some of the steps being followed. Among these are at least two inspections so far. First, goods are received from customers. The goods are inspected. Then the wafers are presorted for film removal. After that a strip and etch process will commence. After these processes are completed, the next inspection of the goods will be made. And once that inspection is done and dusted, polishing work will begin.
And after the polishing process is completed, a seventh step of series-oriented clean, spin, rinse and drying will commence. All these steps, and more, are being monitored by a computerized management system. During the first inspection, wafers are counted. Before processing work begins, the condition or state of the wafers must first be reported. Once the wafers are ready to be presorted for film removal, stripping schedules will be assigned. These are usually applied to multilayered wafers.
Before strip and etch work, wafers need to be compartmentalized into its thickness groups. Strip and etch work entails chemical processing that removes existing patterns and films.