| 摘要 |
In a EUV reflection mask, the distance from the surface of the mask to an idealized plane is locally measured at a first position. The measured value indicates the mechanical stress caused by the alternating layer sequence of a EUV reflection layer. A local value for a radiation dose of an ion beam, which is used to dope the back surface, is calculated for a counter stress that will be produced on the back surface of the substrate. The lattice structure of the substrate is locally influenced by the doping at the position on the back surface corresponding to the first position on the front surface, and the desired counter stress is thereby generated to compensate for bending caused by the stress. It is advantageously possible to compensate for particular local features in the stress distribution on the substrate, in particular, bending and unevenness of relatively high orders.
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