Plasma-induced defect generation on silicon surfaces in HDP-CVD processing

The impact of the HDP-CVD process on Si surfaces has been studied. It has been shown that the sputter component in the process enhances the features and the detection of Si surface defects. These defects, 0.16-0.30 μm in size, are correlated to other characterization techniques such as capacitance-voltage measurements, plasma damage monitoring, and photoconductance decay spectroscopy. We show that these defects are a result of the interaction between the energetic ions in the deposition process and the crystal-originated voids during the Czochralski crystal growth. We show how these defects can be modulated among different processing conditions. The learning has been applied to optimizing the initial steps of plasma deposition in the HDP-CVD process for shallow trench isolation and pre-metal dielectric applications. This work also underscores the importance of applying low information content sensors to the early detection and control of plasma damage in high density plasma applications