High purity is very important throughout
the entire CMP process. Accordingly, the retaining ring also has to
have a high level of purity. This means that the material should not be contaminated by metals, such as aluminum or copper, to avoid scratches on the wafer surface. To prevent other damage to the wafer, the material of the retaining ring should have low outgassing properties.
Usually, standard PPS is used for the retaining rings. PPS is a good choice in general, but there is still room for improvement. TECATRON CMP is a specially modified and improved material designed to meet the requirements of the CMP process, and explained below.
The PPS material TECATRON CMP is characterized by high abrasion and wear resistance, greater than twice the industry standard for PPS (see Chart 1). It has very good thermal and mechanical properties such as high tensile and flexural strength (see Chart 2), which is convenient when cleaning the wafer or during testing. In combination with chemical and solvent resistance, these tribological properties improve the service life of the plastic components.