SHAPING THE FUTURE

The shallow trench isolation (STI) process is a key step in the production of leading-edge integrated circuit devices. Ceria-based slurries are replacing fumed or colloidal silica slurries for the chemical mechanical planarisation (CMP) of STI features. Many methods can be used to produce ceria particles. A comparison was made of CMP defectivity performance of CeO2 particles obtained using three methods which offer the best opportunities for ongoing improvements that will be required to meet the semiconductor industry's demand for reductions in circuit size at each technology node. These methods are: solid state calcination; solution growth; and flame pyrolysis. The results obtained show that the defect performance of CMP slurries made with optimised solid-state CeO2 particles far exceeds that of optimised solution-grown or flame-synthesised CeO2 particles. 5 refs.