Pattern Wafer Defect Characterization Aids Process Results

Axus' fully equipped lab now includes the recent addition of a KLA-Tencor AIT XP+ for defect detection and review on patterned or blanket wafers. Defectivity is an increasingly important aspect of CMP results. Quantification and characterization of defect types is important to the development of processes, especially for those customers who are developing CMP products and consumables. The efficiency of development work is increased because root cause issues can be found and improved quickly.

Wafer Defect mapRecent work with one customer focused on testing of advanced cleaning processes for copper CMP. The new metrology gave Axus an increased sensitivity to smaller defects on certain films and defects that are especially present only on patterned wafers. On two separate occasions during data collection, spikes in defect counts were observed. Using the ability to classify the defects, in both cases it was quickly identified that the primary source of the issue was the quality of the wafers purchased for the work and not the CMP or cleaning processes themselves. With minimal delay, wafers were replaced and Axus was quickly able to confirm that this new material was of suitable quality required to continue with the development work. Especially powerful was the fact that the resulting data aligned well with fab data gathered under similar conditions. That led to confidence that the effects seen at Axus will translate well to the fab. This new capability enables Axus Technology to help customers across a broad range of applications, not just copper and not just CMP.