Patent ID: 8178286

Claim:
A method of making a device, comprising: forming a first photoresist layer over an underlying layer; patterning the first photoresist layer to form a first photoresist pattern comprising a first grid, the first grid comprising a pattern of continuous intersecting bars of material of the first photoresist layer; rendering the first photoresist pattern insoluble to a solvent; forming a second photoresist layer over the first photoresist pattern; patterning the second photoresist layer to form a second photoresist pattern over the underlying layer, the second photoresist pattern comprising a second grid which overlaps the first grid to form a photoresist web, the second grid comprising a pattern of continuous intersecting bars of material of the second photoresist layer; filling openings in the photoresist web with a masking material to form a masking material pattern; removing the photoresist web; and patterning the underlying layer using the masking material pattern.