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As semiconductor device design shrinks, technology requirement for wafer pattern resolution is getting more severe. Requirement for mask pattern resolution is also getting severer due to increase in complexity of mask pattern design. Mask pattern resolution is mainly determined by resist pattern resolution, and adhesion work is known as one of the factors that affects resist resolution. In this paper, the impact of adhesion work on mask resolution was investigated for various hard mask layer (HM). Adhesion work of Ta-base HM is better than Si and Cr-base HM, and resist line resolution on Ta-base HM is better than Si and Cr-base HM. Therefore, ArF attenuated phase shift mask blanks with thin Ta and Ta/Si HM were developed. Line edge roughness (LER) of thin Ta and Ta/Si HM are almost the same as Si-base HM. On the other hand, etching bias uniformity and final line resolution of Ta/Si HM are better than thin Ta HM. Final line resolution of Ta/Si HM is better than Si-base HM. Final space resolution of Ta/Si HM was improved to the same level as Si-base HM with adjustment of HM etching recipe. These evaluation results indicate that the new Ta/Si HM can be a strong candidate capable of enhancing mask resolution on advanced masks for both logic and memory devices.
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