Dose-Modulated Maskless Lithography for the Efficient Fabrication of Compound Eyes With Enlarged Field-of-View

In this paper, a method of dose-modulated maskless lithography (DMML) with high efficiency for the fabrication of a special compound-eyes array with enlarged field-of-view is proposed. Before the fabrication process, practical measurements were primarily conducted to quantify the dose-modulated effect. Next, a digital gray pattern, generated according to the required exposure dose distribution of the design structure, was adopted as a virtual mask to modulate the exposure depth point-by-point. In this way, the whole exposure process requires only one-step. Besides, because the DMML uses sequential gray-levels to modulate the exposure depth, the fabricated structure has a more continuous profile surface. Combined with the thermal reflow process, and the pattern reversion process, the compound eyes array was transferred to the planar polydimethylsiloxane films with high quality. Subsequent tests reveal that the physical performance of fabricated compound eyes array, including the surface profile and the rotated orientation, has a good agreement with our design.