Mask error enhancement factor

However, in the imaging of small features [with sizes <0.75(X/NA) for a contact and <0.5(X/NA) for a line and space], the effective mask dimension error is magnihed and is described by the mask error enhancement factor (MEEF), such that the relation between mask dimension error and wafer line... 

Normal CA resists shown in Chapter 2 are available for immersion lithography. However, significant improvements to immersion lithography are also expected when the refractive index (RI) of the resist is increased beyond the current average value of 1.65. Specifically, theoretical calculations have shown that an increase in the RI of the polymeric resist, to a value around 1.9-2.0, will result in an increase in the exposure latitude, contrast, and mask error enhancement factor (MEET), R(ACD f /ACD, ., i,). A. Whittaker et ai 10,11 have reported that the design and S3mthesis of novel polymers with increased RI achieved 193 resist formulations. An essential part of the discovery process is the use of quantitative structure-property relationship (QSPR) models to predict the RI of small molecules and polymers. ... 

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