The AFM-technology based technique of nanomachining has been well-proven in the area photomask repair since its introduction a decade ago. However, the problems and challenges facing the mask repair operator have changed significantly in this period, and ongoing engineering platform development has reflected these shifts, as well as refinements based on specialized experience with nanomachining repair technology. Improvements from this technical development include improved monitoring and control of the internal tool environment (to minimize AFM scan noise and thermal drift), and automation to easily and reliably clean and characterize the 3-dimensional shape of the NanoBitTM apex. For repair applications, improvements will be shown for the automated and operator-intuitive reconstruction of 3-dimensional nanometer-scale patterns on the photomask with referenced z-depth and xy alignment regardless of pattern orthogonality. Multiple pattern repair capability is also reviewed due to a greater diversity of available process options and multi-repair box capability with a common quartz-level z-reference point. Finally, it will be shown how all of these individual improvements work together to provide extended repair capability down to the 32 nm technology node.
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