Semiconductor device
The present disclosure provides a semiconductor device. The semiconductor device includes a substrate having a first side and a second side opposite to the first side; a first optical element at the first side of the substrate; and a semiconductor stack on the substrate. The semiconductor stack includes a first reflective structure; a second reflective structure; a cavity region between the first reflective structure and the second reflective structure and having a first surface and a second surface opposite to the first surface; and a confinement layer in one of the second reflective structure and the first reflective structure. The semiconductor device further includes a first electrode and a second electrode on the first surface.
1. A semiconductor device comprising:
a substrate having a first side and a second side opposite to the first side;
a first optical element at the first side of the substrate;
a semiconductor stack on the substrate and comprising:
a first reflective structure;
a second reflective structure;
a cavity region between the first reflective structure and the second reflective structure and having a first surface and a second surface opposite to the first surface; and
a confinement layer in one of the second reflective structure and the first reflective structure;
a first electrode on the first surface; and
a second electrode on the first surface,
wherein the substrate, the first optical element and the semiconductor stack are overlapped with each other in a thickness direction of the cavity region, and
wherein the semiconductor device emits a coherent radiation.
2. The semiconductor device according to claim 1 , further comprising a second optical element locates on the second side of the substrate.
3. The semiconductor device according to claim 1 , wherein the material of the first optical element is different from that of the substrate.
4. The semiconductor device according to claim 1 , wherein the first optical element is integral with the substrate.
5. The semiconductor device according to claim 1 , wherein the semiconductor device is configured to emit a radiation to escape to the outside in a direction from the semiconductor stack toward the substrate.
6. The semiconductor device according to claim 1 , wherein the first electrode and the semiconductor stack are overlapped with each other in the thickness direction of the cavity region, and the second electrode and the semiconductor stack are overlapped with each other in the thickness direction of the cavity region.
7. The semiconductor device according to claim 1 , wherein the confinement layer comprises a conductive area and an insulating area surrounding the conductive area, the first optical element and the conductive area are overlapped with each other in the thickness direction of the cavity region.
8. The semiconductor device according to claim 1 , further comprising a conductive layer between the substrate and the semiconductor stack,
wherein the second electrode directly connects to the conductive layer.
9. The semiconductor device according to claim 8 , wherein the cavity region comprises a sidewall between the first surface and the second surface, and the conductive layer extends over the sidewall.
10. The semiconductor device according to claim 1 , further comprising a bonding layer between the substrate and the second electrode.
11. The semiconductor device according to claim 10 , wherein a part of the bonding layer is not overlapped with the first optical element.
12. The semiconductor device according to claim 10 , wherein the bonding layer comprises transparent conducive oxide, metal, insulating oxide, or polymer.
13. The semiconductor device according to claim 1 , wherein the first optical element includes a plurality of protrusions.
14. The semiconductor device according to claim 13 , wherein the shape of one of the protrusions includes rectangle, triangle or semi-circle from a cross-sectional view of the semiconductor device.
15. The semiconductor device according to claim 13 , wherein the protrusions are arranged in a regular pattern or an irregular pattern.
16. The semiconductor device according to claim 13 , wherein one of the protrusions has a height between 0.3 μm and 5 μm.
17. The semiconductor device according to claim 13 , wherein the cavity region includes a plurality of radiation emitting regions, one of the plurality of radiation emitting regions has a first width and two adjacent ones of the plurality of protrusions are separated by a first distance smaller than the first width.
18. The semiconductor device according to claim 13 , wherein the cavity region includes a plurality of radiation emitting regions, one of the plurality of radiation emitting regions has a first width and one of the plurality of protrusions has a second width smaller than the first width.
19. The semiconductor device according to claim 13 , wherein the cavity region includes a plurality of radiation emitting regions, one of the plurality of radiation emitting regions has a first central axis and one of the plurality of protrusions has a second central axis misaligned with the first central axis.
20. The semiconductor device according to claim 13 , wherein the cavity region includes a plurality of radiation emitting regions, and each of two adjacent ones of the plurality of protrusions has a portion overlapping with the same one of the plurality of radiation emitting regions.