Abstract

Proximity printing is a well known lithographic technique. The final density of the resulting patterns is limited by diffraction effects and by the alignment accuracy of the different masks used e.g. for integrated circuit fabrication. To overcome these limitations, a full complex-amplitude modulation proximity printing mask is proposed. A patterned fused silica substrate is used to modulate the phase and a diamond like carbon layer, deposited and patterned on top of the substrate, to modulate the amplitude of the UV light. The proposed diffractive structure modulates both phase and amplitude of the UV exposure beam, forming the required image at a predetermined distance of 50 micron behind the mask.

© 2002 Optical Society of America