Optimization of tungsten chemical mechanical polishing process.
Tan, Eng Hoe.
Date of Issue2003
School of Electrical and Electronic Engineering
In this project, the W-CMP process was improved by extending the polishing pad life by 3 times by evaluating on the 3M diamond conditioner as compared to the standard hard brush conditioner. Furthermore, the effect of Thomas West Inc TW711 hard pad on the reduction of large tungsten area Metal-Insulator-Metal (MIM) capacitor dishing and oxide erosion were investigated, and results obtained saw significantly as much as 60% and 38% less dishing and oxide erosion respectively as compared to Thomas West TW813 soft pad.. Lastly, the effect of diluted slurry of CABOT SSW2000 with water in 1:1 ratio at 2.5% H2O2 concentration was carried out, the process specifications was met and comparable product yield result as non-diluted slurry was observed. Indirectly a significant amount of cost saving and shorter tool down-time for consumables changes were also realized from these experiments.
DRNTU::Engineering::Electrical and electronic engineering::Microelectronics
Nanyang Technological University