Rapid, semi-quantitative depth profiling of ultra-thin films using plasma profiling time-of-flight mass spectrometry: AM: Advanced metrology

Plasma profiling time-of-flight mass spectrometry (PP-TOFMS) is studied for microelectronics applications. Comparative studies with secondary ion time-of-flight mass spectrometry (TOF-SIMS) are presented. PP-TOFMS delivers similar depth-resolved composition information as TOF-SIMS but much faster. For example PP-TOFMS allows assessing the formation of silicides over few nanometers upon annealing of NiPt deposited on Si in only 40 seconds. Secondly, model SiGe / Si superlattice analyses show that standard-free semi-quantitative depth profiles are readily obtained due to low matrix effects and few polyatomic ions being formed. The combination of short analysis time and simple data treatment, makes the PP-TOFMS a useful technique for unexpected contaminant detection. This is illustrated on a stack of FeCoB / SiO
2
deposited on silicon and intended for magnetic sensors applications.