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The decreasing feature sizes as induced by the ITRS have a growing impact on the cost of current and future
photolithographic masks. The assessment, repair and repair validation of these expensive masks has become a very
substantial factor of the total mask production cost. The introduction of immersion lithography and the proposed
introduction of double exposure strategies will further amplify this trend. In order to make the whole procedure more
manageable in a production environment, with its constraints on timing and resource allocation, a seamless workflow of
the repair and validation procedure is sought. A proposed way to achieve this is the set up of a dedicated tool set with a
backbone infrastructure designed for this workflow as well as for the specific high resolution task. In this paper we
concentrate on masks with feature sizes relevant for the 45nm node and defects with typical size and shape as they
appear in production. Phase shifting masks with synthetic defects have been manufactured and the printability of the
defects is analyzed with an AIMSTM45-193i. In part the defect outline and three-dimensional shape as well as further
characteristics have been visualized with an electron microscope, prior to repairing them with an electron beam based
repair system. In addition we will show the behaviour of the phase of the mask in a region of interest, that is in this case
the repair area and its immediate vicinity. This will be done by a special new tool, named Phame®, developed for
measuring the actual phase of smallest mask features with a high spatial resolution.
In the conclusion we will give an outlook how the proposed workflow and the how the employed technologies will
influence the masks that are expected to emerge for the 32nm node.
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