A flat display panel having a first substrate, a display unit disposed on the first substrate, a second substrate disposed on the first substrate to cover the display unit and not covering a predetermined region of the first substrate, a terminal unit disposed on the predetermined region of the first substrate and is electrically connected to the display unit, and a glass strengthener coated on the first substrate and adjacent to the second substrate at a location to increase the strength of the first substrate. The flat display panel having the substrate on which a terminal unit is formed has increased strength.