Large-glass reticle writer: exposure strategy and mask handling

The world semiconductor industry is currently preparing itself for the next evolutionary step in the ongoing development of the integrated circuit, characterized by the 0.18 micrometers technology. These circuits will invariably be produced using conventional optical lithography techniques, but based on advanced photomasks reticles, with the possible assistance of new lithography techniques such as phase shift and optical proximity correction. As such, these reticles will need to be built to very much tighter specifications, with more complex patterns, and at very much smaller geometries, then current technologies. To add to the already complex engineering task for the mask tool makers, the new SEMI reticle standard will introduce a 230 mm by 230 mm large and 9 mm thick quartz glass blank that will have a weight of above one kilogram. The production of these advanced masks is therefore identified as a key enabling technology which will stretch the capabilities of the manufacturing process, and its equipment, to the limit.