High Intensity UV-LED Mask Aligner for Applications in Industrial Research

In this paper we show first results on a semi-automatic mask aligner with UV-lEd illumination, SUSS Ma/Ba8 Gen4 Pro equipped with a UV-lEd lamp house and Mo Exposure optics [8]. The tool offers a customer-controllable spectrum with three wavelengths corresponding to the mercury i, g and h-line. The field-proven MO-Exposure optics guarantees a reliable, smooth angular spectrum that can be fully customized. Full 8-inch wafers were exposed with the same high intensity and light uniformity as with standard 1 kW mercury lamps. Broadband and single line exposures were performed on several standard processes. The resolution and appearance of the produced features compared well to traditional exposures with a mercury lamp. In addition, we present an analysis of the eco-fingerprint of our UV-lEd-lithography system. For a semi-automatic system used under typical research institute conditions, the lEd light source can survive a machine life-time. lEds don ́t require warm up times and thus are switched on during exposure only. Moreover, low power consumption of the lEds during operation and no need for nitrogen flow cooling also contribute to very low running cost and a green footprint.in summary, the lithography industry will greatly benefit from UV-lEd illumination, paving the way for future process innovations in a mercury-free and safe environment.