Trimming lithography part II: An effect of trimming distance to the sub-resolution pattern quality

Trimming lithography acts as one of the candidates for next generation lithography. The pattern size can be scaled by adjusting the trim distance that is much bigger than an original design linewidth. The photoresist feature size can be scaled down to 0.18 µm with the 0.9 µm mask and the 0.5 µm resolution exposure tool. However, a pattern density of the line/space pattern is lower than that of other patterning techniques. Different pattern qualities between dense and isolated patterns are explained by a diffraction of the waveform transmitted through the mask slit.