The present invention is directed to a thick film conductor composition comprised of (a) aluminum-containing powder; (b) amorphous silicon dioxide (c) and one or more optional glass frit compositions; dispersed in (d) organic medium. The amorphous silicon dioxide contributes to significant bow reduction tendency for solar cells thinner than 270 microns and larger than five inches square without significant effect on reducing the electrical performance of the fired solar cell. In addition and as preferred by solar cell manufacturers, the addition of glass frit reduces the dusting tendency of the aluminum thick film composition.