A display device includes an array substrate, a driving film and an adhesive member. The array substrate includes a first base substrate, a plurality of first signal pads formed on the first base substrate and a first dummy pad formed adjacent to the first signal pads. The driving film includes a base film, a plurality of output terminals formed on the base film and a first alignment mark formed adjacent to the output terminals. The adhesive member adheres the first signal pads to the output terminals, and adheres the first dummy pad to the first alignment mark.