Chemical amplification techniques and methods for developable bottom antireflective coatings and stained implant resists

摘要

The present invention describes methods for patterning photosensitive layers (e.g., photoresist on anti-reflective coatings) on a semiconductor substrate with PS-CAR (PS-CAR: photosensitive chemically amplified resist) chemistries. In one embodiment, areas having a higher acid concentration in a photoresist layer may be formed by a two-step exposure process. The PS-CAR chemicals can include photoacid generators (PAGs) and photosensitizer elements that can enhance the decomposition of the PAGs to acid. The first exposure may be a structured EUV or UV exposure that produces an initial amount of acid and photosensitizer. The second exposure may be a non-EUV flood exposure that excites the photosensitizer, which increases the acidification rate when the photosensitizer is in the layer stack. The distribution of energy at the exposures may be optimized using certain properties (eg, thickness, refractive index, doping) of the photoresist layer, a layer underneath, and / or an overlying layer.