Mask making process development and control is addressed using a reticle inspection tool equipped wityh the new revolutionized application called LBM-Linewidth Bias Monitoring. In order to use the LBM for mask-making process control, procedures and corresponding test plates are a developed, such that routine monitoring of the manufacturing process discloses process variation and machine variation. At the same time systematic variation are studied and either taken care of or taken into consideration to allow successful production line work. In this paper the contribution of the LBM for mask quality monitoring is studied with respect to dense layers, e.g. dRAM. Another aspect of this application - the detection of very small (20nm and beyond) CD mis-uniformity areas is discussed.
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