Nano-structure semiconductor light emitting device
A nano-structure semiconductor light emitting device includes a base layer formed of a first conductivity type semiconductor, and a first insulating layer disposed on the base layer and having a plurality of first openings exposing partial regions of the base layer. A plurality of nanocores is disposed in the exposed regions of the base layer and formed of the first conductivity-type semiconductor. An active layer is disposed on surfaces of the plurality of nanocores and positioned above the first insulating layer. A second insulating layer is disposed on the first insulating layer and has a plurality of second openings surrounding the plurality of nanocores and the active layer disposed on the surfaces of the plurality of nanocores. A second conductivity-type semiconductor layer is disposed on the surface of the active layer positioned to be above the second insulating layer.
1. A nano-structure semiconductor light emitting device comprising:
a base layer formed of a first conductivity type semiconductor;
a first insulating layer disposed on the base layer and having a plurality of first openings exposing partial regions of the base layer;
a plurality of nano-light emitting structures, each comprising a nanocore disposed in the exposed regions of the base layer and formed of the first conductivity-type semiconductor and a shell including an active layer and a second conductivity-type semiconductor layer sequentially disposed on a surface of the nanocore; and
a second insulating layer disposed on the first insulating layer and having a plurality of second openings surrounding the nanocore and the active layer,
wherein the second openings have a diameter greater than that of the first openings, and a portion of the first insulating layer in a perimeter of the first openings is exposed by the second openings;
wherein the active layer is entirely positioned above the exposed portion of first insulating layer and the second conductivity-type semiconductor layer is entirely positioned above the second insulating layer.
2. The nano-structure semiconductor light emitting device of claim 1 , wherein regions of the nanocores positioned in the second openings have a sectional area greater than upper and lower regions thereof.
3. The nano-structure semiconductor light emitting device of claim 1 , wherein the first and second insulating layers are made of a same material.
4. The nano-structure semiconductor light emitting device of claim 1 , wherein the first and second insulating layers have different etching rates under same etching conditions.
5. The nano-structure semiconductor light emitting device of claim 4 , wherein an etching rate of the second insulating layer is higher than that of the first insulating layer.
6. The nano-structure semiconductor light emitting device of claim 4 , wherein the first and second insulating layers are made of different materials or have different air gap densities.
7. The nano-structure semiconductor light emitting device of claim 1 , wherein
the second insulating layer is made of a material obtained by oxidizing a material of the first insulating layer.