マスク基板の支持法に関する研究

抄録

The continued demand by the integrated circuit industry for higher device densities has placed requirements on the photolithographic manufacturing system for high accurate photomasks. To obtain the desired photomasks, decrease of pattern distortions due to bending of a photomask-substrate, as well as positioning accuracy of electron beam, is needed. In the case of unforced support, for example, this bending is caused by its own weight and by strains between the structured coating and the substrate. This paper shows that, in the condition of cylindrical bending substrate with simply supported edges, adequate bending moments in its supporting points minimizes the pattern distortions and linear gain correction in writing positions makes same effect to them. This paper also shows the examples of substrate flatness supported in a 8 supports holder, minimizing the substrate bending by additional bending moments in its supporting points.