Application of CDU master for 40-nm critical layer CD control: Strategies and results

摘要

Critical Dimension Uniformity (CDU) is one of the critical parameters to assure good performance and reliable functionality of sub 40 nm node logic process. CD uniformity control is also one of key issues in mass production. In this paper, we will introduce our latest software which is named CDU Master, The Nikon CDU Master can derive the optimal control parameters for each compensation function in the scanner using the exposure dose and focus correction data, the high degree of controllability of NSR-S620 scanner enables precise correction of the complicated CD error distribution. Finally, use this system, intra-wafer CDU of 40nm critical layer is improved by 34%, achieve the goal of the process control.