Effect of Phase Error on Lithographic Characteristics Using Attenuated Phase-Shifting Mask

概要

論文の詳細を見る
An attenuated phase-shifting mask is one of the most useful technologies for sub-half-micron lithography. However, it is necessary to control new parameters such as phase or transmittance when a phase-shifting mask is applied to practical use. We investigated the effect of phase error on lithographic characteristics for a hole pattern using an attenuated phase shifting mask. It is found that a phase error causes a decrease of depth of focus (DOF) and shift of best focus position. It is indicated that this effect depends on several optical parameters such as holesize and wavelength. In the case of the 0.4 μm hole pattern with i-line stepper, the phase tolerance must be less than 2.7° to control loss of DOF within 0.1 μm. It is also found that the edge slope effect of the shifter is rather small and the side wall angle of 70° is acceptable.
社団法人応用物理学会の論文
1994-12-30