A novel angle-resolved scatterometer based on pupil optimization for feature profile measurement in a photolithography process is proposed. The impact of image sensor errors is minimized by optimizing the intensity distribution of the incident light using a spatial light modulator. The scatterometry sensitivity of feature measurement at different polarization conditions is calculated using the rigorous coupled-wave and first-order analyses, and the reproducibility of the scatterometer is evaluated. The results show that the sensitivity and reproducibility of the angle-resolved scatterometer increase by 90% and 40% with pupil optimization, respectively.
© 2012 Chinese Optics Letters
(050.1950) Diffraction and gratings : Diffraction gratings
(120.3940) Instrumentation, measurement, and metrology : Metrology
(120.5820) Instrumentation, measurement, and metrology : Scattering measurements
Instrumentation, Measurement, and Metrology
Fan Wang, Hailiang Lu, Qingyun Zhang, and Anatoly Burov, "Novel technique for characterizing feature profiles in photolithography process," Chin. Opt. Lett. 10, 061202- (2012)