Removing Subsurface Damage by Chemical Mechanical Planarization (CMP)

Chemical Mechanical PlanarizationA prevailing trend in the technology manufacturing industry is the need for smaller, thinner silicon wafers. Although the conventional diamond grinding and laser processes do well in preparing wafers, these methods still have limits.


A side effect of the wafer grind process is damage to the subsurface. This can compromise the composition of a wafer, and these imperfections need to be removed. Silicon wafer polishing addresses this issue and allows for thinner, stronger, and more robust products.


How Silicon Wafer Polishing Works

Silicon wafer polishing, also known as Chemical Mechanical Planarization, is a process that removes the peaks and valleys associated with subsurface damage. It also removes stress and surface damage.


Polishing works by putting vacuum pressure on a wafer. It is slowly put in contact with a rotating platen that is fitted with a polishing pad. Meanwhile, a diamond liquid slurry is sprayed on the polishing surface. Together, the polishing pad and slurry grind away imperfections. The silicon wafer polishing process can remove between 5 and 10 microns from a wafer.


Often, silicon wafer polishing is a post-process step that takes place after back grinding. This step is often necessary in order to create more powerful microchips or other electronics.


Many technology manufacturing companies utilize wafer polishing as part of their everyday operations. As the development of more complex electronics increases, the demand for this service will also increase.