Analytical techniques for measuring contamination introduced during ion implantation

Contamination introduced during ion implantation, including transition metals, mobile ions, carbon and particulates can be deposited on the surface of the Si wafer or can be co-implanted to depths of 100s of angstroms. Tools used today to measure these contaminants include magnetic sector SIMS (Secondary Ion Mass Spectrometry), quadrupole SIMS, (TOF) Time of Flight SIMS, surface SIMS or “O” (Oxygen)-leak SIMS, Total Reflection X-Ray Fluorescence (TXRF), Vapour Phase Decomposition (VPD)-TXRF, VPD-AA (Atomic absorption) and Minority Carrier LifeTime (MCLT). In this paper, some of the advantages and shortfalls of using the above techniques are considered for the measurement of heavy metals, mobile ions, aluminium and cross-contamination of dopants introduced during ion implantation