Optimization of low-k dielectric (fluorinated SiO/sub 2/) process and evaluation of yield impact by using BEOL test structures

This work describes the optimization of low-k dielectric process and evaluation of yield impact by using back end of line (BEOL) test structures. Three splits of the low-k dielectric process were compared with high-density-plasma un-doped-silicon-glass (HDP-USG) process and are electrically characterized with the test structures of the BEOL unit process and integration process parameter extraction. The interconnect capacitance is used as the optimization criteria of low-k dielectric process and the yield impact is reviewed for the concern of manufacturing.