Display device and method of manufacturing the same

A display device, comprising:

• a substrate;
• a first layer disposed on the substrate, the first layer including a first portion having a first thickness and a second portion having a second thickness greater than the first thickness;
• a second layer disposed on the first layer;
• an active pattern disposed on the second layer, the active pattern overlapping only the first portion of the first layer;
• a gate electrode disposed on the active pattern;
• a source electrode and a drain electrode disposed on the gate electrode, the source electrode and the drain electrode being connected to the active pattern;
• a first electrode connected to one of the source electrode and the drain electrode;
• a pixel defining layer disposed on the first electrode, the pixel defining layer having an opening portion exposing at least a portion of the first electrode;
• an emission layer in the opening portion disposed on the first electrode;
• and
• a second electrode disposed on the emission layer.