Substrate for fabricating light emitting device and light emitting device fabricated therefrom
The invention provides a substrate for fabricating a light emitting device and the light emitting device fabricated therefrom. The substrate includes at least one platform region having a first facet direction for epitaxial growth; and a plurality of continuous protruded portions surrounding the at least one platform region to isolate the at least one platform region from another platform region, wherein the first facet direction is substantially excluded from facet directions of the plurality of continuous protruded portions. Since facet directions of the plurality of continuous protruded portions substantially do not include the first facet direction, during formation of the light emitting device, epitaxial growth is mainly conducted on the at least one platform region, which may prevent epitaxial defects from generating and enhance external quantum efficiency of the light emitting device.
1 . A substrate for fabricating a light emitting device, comprising:
at least one platform region having a first facet direction for epitaxial growth; and
a plurality of continuous protruded portions surrounding the at least one platform region to isolate the at least one platform region from another platform region,
wherein the first facet direction is substantially excluded from facet directions of the plurality of continuous protruded portions.
2 . The substrate according to claim 1 , wherein the plurality of continuous protruded portions have a curved surface.
3 . The substrate according to claim 1 , wherein the plurality of continuous protruded portions have a flat surface.
4 . The substrate according to claim 1 , wherein the first facet direction is (0001) facet direction for C-plane sapphire.
5 . The substrate according to claim 1 , wherein the substrate is formed of sapphire or a silicon-comprising material.
6 . A light emitting device, comprising:
a substrate comprising at least one platform region having a first facet direction for epitaxial growth; and a plurality of continuous protruded portions surrounding the at least one platform region to isolate the at least one platform region from another platform region, the first facet direction being substantially excluded from facet directions of the plurality of continuous protruded portions;
an epitaxial stacking structure provided on the substrate, sequentially comprising a first semiconductor layer, a light emitting layer, and a second semiconductor layer along a stacking direction, the first semiconductor layer comprising a first portion which is not covered by the light emitting layer and the second semiconductor layer;
a first electrode engaged with the first portion of the first semiconductor layer; and
a second electrode engaged with the second semiconductor layer and electrically separated from the first electrode.
7 . The light emitting device according to claim 6 , wherein the first semiconductor layer is an n-type semiconductor and the second semiconductor layer is a p-type semiconductor.
8 . The light emitting device according to claim 6 , wherein the plurality of continuous protruded portions have a curved surface.
9 . The light emitting device according to claim 6 , wherein the plurality of continuous protruded portions have a flat surface.
10 . The light emitting device according to claim 6 , wherein the substrate is formed of sapphire or a silicon-comprising material.
11 . A substrate for fabricating a light emitting device, comprising:
at least one platform region served as a primary platform for epitaxial growth; and
a plurality of continuous protruded portions surrounding the at least one platform region to isolate the at least one platform region from another platform region.
12 . A light emitting device having the substrate according to claim 11 , further comprising:
an epitaxial stacking structure provided on the substrate, sequentially comprising a first semiconductor layer, a light emitting layer, and a second semiconductor layer along a stacking direction, the first semiconductor layer comprising a first portion which is not covered by the light emitting layer and the second semiconductor layer;
a first electrode engaged with the first portion of the first semiconductor layer; and
a second electrode engaged with the second semiconductor layer and electrically separated from the first electrode.