Single Particle Inductively Coupled Plasma Mass Spectrometry Metrology for Advanced Semiconductor CMP Process Development

This work describes advanced metrology based on Single Particle Inductively Coupled Plasma Mass Spectrometry (sp-ICP-MS) used in chemical mechanical planarization (CMP) process development. sp-ICP-MS was used to measure concentrations and sizes of ceria nanoparticles before and after CMP of silicon dioxide. Changes in the particle size distribution show a shift to lower median particle size after polishing, and an increase in the number of smaller particles. This result is consistent with previous reports which showed significant in- process reduction of the average ceria particle size after polishing. These new results are important because they demonstrate the application of sp-ICP-MS in the development of advanced CMP processes.