Abstract
We have been developing a new laser annealing technology with a micro lens array (MLA). In this
technology, an Nd: YAG laser is irradiated onto a specifi c local area using MLA that only targets the
channel area of the thin-fi lm transistor (TFT) inside sub pixels on a TFT backplane substrate for fl at
panel displays. However, due to the high coherency of Nd: YAG lasers, illuminating MLA at good
uniformity is diffi cult by standard illumination optics. Therefore, we developed a new laser scramble
unit that spatially shifts the laser beam at high speeds to reduce the illumination MURA caused by
interference fringes. Using this laser scramble unit, we illuminated MLA and only annealed a-Si fi lm on
the channel region of the simple TFT structure at good uniformity. We also confi rmed improvement in
the electron mobility of the TFT annealed by this laser irradiation system.
