Spectroscopic ellipsometric analysis of a patterned Cr film on quartz

Spectroscopic ellipsometry (SE) has come to be an important method to determine the critical dimension (CD) of patterned structures by measuring the zeroth-order diffraction response at a fixed angle of incidence. To prove the validity of this method under metallic environment, we performed SE measurements on a ID patterned Cr thin film on quartz whose separation was 300 nm. The SE spectra were obtained at several angles of incidence to confirm the results. The rigorous coupledwave analysis (RCWA) calculation could explain the measured spectra within the experimental error, proving that the SE technique could be easily extended to the 0.07 μm generation.