STI CMP Endpoint Robustness Improvement through Stribeck Curve Study

Inhalt:
In this study, we investigated the tribological behaviors of oxide and nitride blanket wafers polished on hard porous polyurethane pad using different ceria based slurries with a multitude of changes in polishing pressure and sliding velocity. We first proposed a new methodology that can be used to select STI CMP process that meets process control specifications required for qualification in mass production and meets the nanotopography specifications required for advanced technology nodes. We will further discuss on different high selective slurry process performances like planar efficiency and compare their tribological behaviors in order to obtain significant oxide to nitride torque difference that is required in the industry in terms of process robustness and stability. Keywords: Shallow Trench Isolation Chemical Mechanical Planarization, Friction torque, Motor current endpoint system, Stribeck curve, High selective slurry process.