A two-dimensional dense array of contact holes can be printed on a negative photoresist employing a combination of a quadrupole illumination lens and a lithographic mask including a criss-cross pattern of opaque lines. The openings in the quadrupole illumination lens are aligned along the perpendicular directions of the opaque lines. Discrete contact holes can be printed on a negative photoresist employing a combination of a quadrupole illumination lens and a lithographic mask including a criss-cross pattern of opaque subresolution assist features and discrete opaque cross patterns. Alternately, a two-dimensional array of contact holes can be printed on a negative photoresist employing a quadrupole illumination lens and a checkerboard pattern of openings. The openings in the quadrupole illumination lens are in diagonal directions.