Light-emitting diode (LED) array

1. A light-emitting diode array having a first area, a third area, and a second area comprising:

a permanent substrate;

a bonding layer on the permanent substrate;

a second conductive layer on the bonding layer;

a second isolation layer on the second conductive layer;

a crossover metal layer on the second isolation layer;

a first isolation layer on the crossover metal layer;

a conductive connecting layer on the first isolation layer except the third area;

an epitaxial structure on the conductive connecting layer, wherein the epitaxial structure further comprises a rough surface; and

a first electrode layer on the epitaxy structure.

2. The light-emitting diode array of claim 1 , wherein the array comprises a first light-emitting diode unit, a second light-emitting diode unit in sequence to a (N−1) th light-emitting diode unit, a N th light-emitting diode unit, and multiple pathways among the N light-emitting diode, wherein N is not less than three; wherein the first light-emitting diode unit locates in the first area, the N th light-emitting diode unit locates in the third area, and the second light-emitting diode unit in sequence to the (N−1) th light-emitting diode unit locate in the second area located between the first area and the third area, wherein the N light-emitting diode units are electrically connected to each other by the crossover metal layer in series.

3. The light-emitting diode array of claim 1 , wherein the epitaxial structure comprising:

a second conductive semiconductor layer;

an active layer on the second conductive semiconductor layer;

a first conductive semiconductor layer on the active layer; and

a plurality of trenches, wherein the trenches extend from the second conductive semiconductor layer to the first conductive semiconductor layer except in the third area.

4. The light-emitting diode array of claim 3 , wherein the first isolation layer locates on the side wall of the trenches and the crossover metal layer extends into the trenches.

5. The light-emitting diode array of claim 1 , wherein the conductive connecting layer in the third area locates between the epitaxial structure and a part of the crossover metal layer, and the conductive connecting layer in the first area locates between the epitaxial structure and the second conductive layer.

6. The light-emitting diode array of claim 1 further comprising:

a conductive region located on the conductive connecting layer in the second area and is not covered by the first isolation layer; and

an electrical isolation region not covered by the crossover metal layer and is adjacent to the conductive region.

7. The light-emitting diode array of claim 3 , wherein the crossover metal layer is electrically isolated from the second conductive semiconductor layer by the first isolation layer.