From Event: SPIE Advanced Lithography, 2018
Metrology plays an important role in edge placement error (EPE) budgeting. Control for multi-patterning applications as new critical distances needs to be measured (edge to edge) and requirements become tighter and tighter in terms of accuracy and precision. In this paper we focus on imec iN7 BEOL platform and particularly on M2 patterning scheme using SAQP + block EUV for a 7.5 track logic design. Being able to characterize block to SAQP edge misplacement is important in a budgeting exercise (1) but is also extremely difficult due to challenging edge detection with CD-SEM (similar materials, thin layers, short distances, 3D features). In this study we develop an advanced solution to measure block to SAQP placement, we characterize it in terms of sensitivity, precision and accuracy through the comparison to reference metrology. In a second phase, the methodology is applied to budget local effects and the results are compared to the characterization of the SAQP and block independently.
© (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
A. Charley, P. Leray, G. Lorusso, T. Sutani, and Y. Takemasa, "Advanced CD-SEM solution for edge placement error characterization of BEOL pitch 32nm metal layers," Proc. SPIE 10585, Metrology, Inspection, and Process Control for Microlithography XXXII, 1058519 (Presented at SPIE Advanced Lithography: February 28, 2018; Published: 16 March 2018); https://doi.org/10.1117/12.2298408.