A display panel includes a method of fabricating an array substrate. The method includes forming a metal layer (1) on a substrate, and patterning the metal layer (1) using a phase shift mask to form a pattern of metal wiring. The phase shift mask includes a substrate and a wiring light shielding portion (02) on the substrate (01). The wiring light shielding portion (02) includes a light shielding region (021) and a phase shift region (022). In a direction perpendicular to the extending direction of the wiring light shielding portion (02) a width of the light shielding region (021) is larger than a width of the pattern of the metal wiring formed by the wiring light shielding portion (02).