CD Error Caused by Aberration and Its Possible Compensation by Optical Proximity Correction in Extreme-Ultraviolet Lithography

Abstract

There has been reports of EUV scanner aberration effects to the patterns down to 18 nm half-pitch (hp). Maximum aberration of the latest EUV scanner is reported as 25 mλ. We believe that the first EUV mass production will be applied to the devices of 16 nm hp, so that we checked the aberration effects on 16 nm periodic line and space patterns and nonperiodic double and five-bar patterns. Coma aberrations of Z7, Z8, Z14 and Z15 Zernike polynomials (ZP) seems to be the dominant ones that make pattern distortion. Non-negligible critical dimension (CD) variation and position shift are obtained with the reported maximum 25 mλ of coma aberration. Optical proximity correction (OPC) is tried to see if this aberration effects can be minimized, so that we can make the desired patterns even though there is a non-correctable scanner aberration. © 2017 SPIE.