An organic EL display device has a substrate, a plurality of organic EL
elements formed on the substrate and a plurality of thin film transistors
formed on the substrate. The transistors are connected to the respective
EL elements for controlling current applied to the respective elements.
Each of the transistors includes an active layer of semiconductor
material, formed on the substrate, a source region and a drain region
being formed in the active layer, a source electrode of aluminum material
electrically coupled to the source region formed in the active layer, a
drain electrode of aluminum material electrically coupled to the drain
region formed in the active layer, an insulation layer formed on the
active layer, a gate electrode formed on the insulation layer, a first
barrier metal layer of titanium nitride containing equal to or less than
50 atm % of nitrogen or titanium, inserted between the source electrode
and the source region of the active layer, and a second barrier metal
layer of titanium nitride containing equal to or less than 50 atm % of
nitrogen or titanium, inserted between the drain electrode and the drain
region of the active layer.
