In situ remote RF plasma cleaning and surface characterization after silicon dioxide/silicon RIE

In IC fabrication, etching (patterning) technology is one of the fundamental techniques. Dry etching has replaced wet etching for patterning micron and submicron features in advanced microelectronics device fabrication. Due to the dry etching induced surface modifications and damage, post-etch cleanings are necessary and critical to device fabrication. Similarly, dry cleaning or gas phase cleaning technologies have shown promise in cleaning processes where conventional wet cleans are impractical or inadequate.;The focus of this thesis is the investigation of dry surface cleaning and conditioning after reactive ion etching (RIE) of SiO2 on Si. The approach is to employ in situ remote RF H2 plasma and H2/SiH4 plasma processes for RIE induced CFx residue removal and a final H-passivation of the Si surface. The major scientific issue is to develop understanding of the plasma processes that effectively remove contaminants yet do not damage existing layers.;Our investigation suggests that a remote H2 plasma process is effective in removing RIE induced CFx residue and chlorine-containing residue. With the addition of ∼0.1% of SiH4, the remote H 2/SiH4 plasma has proven to be more effective in removal of residual oxide contamination. The plasma cleaning processes have been successfully developed to be fully in situ and cluster tool compatible. The processes were optimized for surface residue and via residue removal on 150 mm interconnect patterned wafers. SEM images showed that a significant amount of surface and via residue were removed. Finally, by using the cobalt silicide formation process and the Schottky diode electrical properties as two test vehicles, we demonstrated the importance of post-RIE cleaning and evaluated the remote plasma cleaning techniques as dry surface cleaning processes.