Light emitting device having columnar parts surrounded by concavo-convex shapes and projector
View Patent ↗A light emitting device includes a substrate, a first semiconductor layer provided to the substrate, a laminated structure disposed at an opposite side to the substrate of the first semiconductor layer, and including a plurality of columnar parts, a first electrically-conductive layer as a surface layer at laminated structure side in the first semiconductor layer, and a second electrically-conductive layer opposed to the first electrically-conductive layer via the laminated structure, wherein the columnar part includes a light emitting layer configured to emit light, a second semiconductor layer which is disposed between the light emitting layer and the first electrically-conductive layer, and a third semiconductor layer disposed between the light emitting layer and the second electrically-conductive layer, concavo-convex shapes are formed on a surface of the first electrically-conductive layer, an insulating layer is disposed on the first electrically-conductive layer, and electrode layers are disposed so as to cover an area where the insulating layer is disposed, and some of the concavo-convex shapes.
1. A light emitting device comprising:
a substrate;
a first semiconductor layer provided to the substrate, the first semiconductor layer being divided into a center area and a peripheral area surrounding the center area;
a laminated structure disposed on the first semiconductor layer, the laminated structure including a plurality of columnar parts, the plurality of columnar parts being disposed at the center area of the first semiconductor layer;
a first electrically-conductive layer disposed on the peripheral area of the first semiconductor layer; and
a second electrically-conductive layer disposed on a top of the plurality of columnar parts, wherein
each of the plurality of columnar parts includes:
a light emitting layer configured to emit light in response to injection of an electrical current from one of the first electrically-conductive layer and the second electrically-conductive layer;
a second semiconductor layer which is disposed between the light emitting layer and the first electrically-conductive layer, and is same in conductivity type as the first semiconductor layer; and
a third semiconductor layer which is disposed between the light emitting layer and the second electrically-conductive layer, and is different in conductivity type from the second semiconductor layer,
concavo-convex shapes are formed on a surface of the first electrically-conductive layer in the peripheral area of the first semiconductor layer,
an insulating layer is disposed on the first electrically-conductive layer having the concavo-convex shapes in the peripheral area of the first semiconductor layer, and
an electrode layer is disposed so as to cover an area where the insulating layer is disposed, and some of the concavo-convex shapes.
2. The light emitting device according to claim 1 , wherein
the concavo-convex shapes are irregularly formed.
3. The light emitting device according to claim 1 , wherein
the plurality of columnar parts are regularly arranged in a plan view, and
the concavo-convex shapes are regularly disposed.
4. The light emitting device according to claim 1 , wherein
the insulating layer is formed using a coating-type insulating material.
5. The light emitting device according to claim 1 , wherein
the electrode layer is formed including three layers of chromium, nickel, and gold.
6. A projector comprising:
the light emitting device according to claim 1 .