Semiconductor light emitting device and method of fabricating semiconductor light emitting device
View Patent ↗A semiconductor light emitting device has a light emitting element, a first electrode layer, a second electrode layer, a seed electrode layer and a plated layer. The light emitting element has a nitride-based III-V compound semiconductor on a substrate. The light emitting element having a light extraction surface. The first electrode layer on the light extraction surface. The second electrode layer is provided on a surface opposite to the light extraction surface of the light emitting element. The seed electrode layer is configured to cover the entire surface of the second electrode layer. The plated layer is provided on the seed electrode layer. The light emitting element has a light emitting layer, a first conductive type semiconductor layer, and a second conductive type semiconductor layer. The light emitting element has a forward tapered shape of a width which gradually narrows in order of the second conductive type semiconductor layer, the light emitting layer and the first conductive type semiconductor layer.
1. A semiconductor light emitting device, comprising:
a light emitting element comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer and a light emitting layer disposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer;
a first electrode layer connected to the first conductive type semiconductor layer;
a second electrode layer disposed under the second conductive type semiconductor layer so that all of one surface of the second electrode layer contacts the second conductive type semiconductor layer;
a first metal layer configured to cover a bottom surface and a side surface of the second electrode layer, the first metal layer having a step in accordance with an outline of the second electrode layer; and
a second metal layer disposed under the first metal layer, the second metal layer having a step in accordance with a shape of the first metal layer in a surface opposite to a surface contacting the first metal layer,
wherein the light emitting element has a forward tapered shape of a width which gradually narrows in order of the second conductive type semiconductor layer, the light emitting layer and the first conductive type semiconductor layer.
2. The device according to claim 1 ,
wherein the first metal layer comprises:
a first layer which covers the bottom surface and the side surface of the second electrode layer and includes a metal material capable of preventing a metal in the second metal layer from being diffused in the second electrode layer; and
a second layer which contacts the first layer and the second metal layer and mingles with the metal in the second metal layer.
3. The device according to claim 2 ,
wherein the second electrode layer comprises a highly reflective electrode layer which contacts the first layer and reflects light emitted by the light emitting layer;
the first layer has a surface area larger than a surface area of the highly reflective electrode layer; and
the first layer has a thickness larger than a thickness of the highly reflective electrode layer.
4. The device according to claim 1 , further comprising:
a ground electrode layer having a structure of laminating a barrier metal layer and a ground electrode.
5. The device according to claim 1 , further comprising:
an insulating film configured to cover a sidewall of the forward tapered shape of the light emitting element.