TOP ANTI-REFLECTIVE COATINGS VS BOTTOM ANTI-REFLECTIVE COATINGS

TARC vs BARC

Anti-reflective coatings are an essential part of photolithography with the continual shrinking of pattern geometries. Anti-reflective coatings reduce reflectivity at resist interfaces, thus providing better line width control with minimal loss of resist performance. The reflectivity is reduced by either attenuating light that passes through the anti-reflective coatings or by matching the index of refraction of the anti-reflective coatings to the resist system at the exposure wavelength employed.