The invention includes masking methods. In one implementation, a masking material which includes boron doped amorphous carbon is formed over a feature formed on a semiconductor substrate. The masking material includes at least about 0.5 atomic per cent boron. The masking material is substantially anisotropically etched effective to form an anisotropically etched sidewall spacer which includes theboron doped amorphous carbon on a sidewall of the feature. The substrate is then processed proximate the spacer while using the boron doped amorphous carbon-including spacer as a mask. After processing the substrate proximate the spacer, the boron doped amorphous carbon-including spacer is etched from the substrate. Other implementations and aspects are contemplated.