Interconnects Electrical Parametric Variability Control for Automotive Manufacturing

The control of interconnects resistance, intra- and inter-capacitance (RC) variations in order to meet the stringent automotive sigma requirements is an extremely challenging task in the advanced semiconductor manufacturing due to many process variables to control in the dual damascene integration scheme. We demonstrate that the key interconnects parametric are able to meet Cp/Cpk >1.67 with a combination of real-time in-line automatic process control (APC) of trench critical dimension (CD), trench depth, and copper Chemical Mechanical Polish (CMP) that are well correlated to the parametric performance. We explain how the APC is modeled using feed-forward and feed-backward data to obtain optimum processing conditions for automotive manufacturing by using stochastic in-line data for analysis and control of subsequent upstream and downstream process. Employing variance component analysis, we show that the RC’s overall sigma can be improved. Further, the bivariate analysis is shown for parametric output to check on centering to ensure the technology response of interconnect model is maintained as designed.