Light-emitting element, method of manufacturing light-emitting element, and display device including light-emitting element

A method of manufacturing a light-emitting element, the method comprising:

• forming a first semiconductor layer, a first barrier layer, an active layer, a second barrier layer, a second semiconductor layer, and an electrode on a substrate to form a light-emitting stack;
• vertically etching the light-emitting stack to form at least one light-emitting stack pattern and externally exposing one region of the first semiconductor layer;
• performing heat treatment on the at least one light-emitting stack pattern so that each of the first barrier layer and the second barrier layer includes a first region and a second region, the first region and the second region including different materials;
• forming an insulating material layer on the at least one light-emitting stack pattern and vertically etching the insulating material layer to form an insulating film surrounding a surface of the light-emitting stack pattern;
• and
• separating the at least one light-emitting stack pattern surrounded by the insulating film from the substrate to form a light-emitting element, wherein
• the light-emitting element includes the first semiconductor layer, the first barrier layer, the active layer, the second barrier layer, the second semiconductor layer, and the electrode disposed in a length direction of the light-emitting element,
• the first region of each of the first barrier layer and the second barrier layer includes a semiconductor layer having an aluminum composition higher than an aluminum composition of the first semiconductor layer, the active layer, and the second semiconductor layer, and
• the second region of each of the first barrier layer and the second barrier layer includes an oxide layer.

A display device comprising:

• a first electrode and a second electrode disposed on a substrate in a first direction and extending in a second direction different from the first direction, the first electrode and the second electrode being spaced apart from each other;
• and
• a plurality of light-emitting elements disposed between the first electrode and the second electrode, wherein
• each of the plurality of light-emitting elements includes:
• a first end portion and a second end portion disposed in a length direction of the light-emitting element;
• a first semiconductor layer disposed at the first end portion;
• a first barrier layer disposed on the first semiconductor layer and including a first region and a second region;
• an active layer disposed on the first barrier layer;
• a second barrier layer disposed on the active layer and including a third region and a fourth region;
• a second semiconductor layer disposed on the second barrier layer;
• a third electrode disposed on the second semiconductor layer;
• and
• an insulating film surrounding an outer circumferential surface of each of the first semiconductor layer, the first barrier layer, the active layer, the second barrier layer, the second semiconductor layer, and the third electrode,
• the first region and the third region include a semiconductor layer having an aluminum composition higher than an aluminum composition of the first semiconductor layer, the active layer, and the second semiconductor layer, and
• the second region and the fourth region include an oxide layer.