Light Emitting Diode and Fabrication Method Thereof

A vertical light-emitting diode (LED) chip, comprising from bottom up:

• a conductive substrate;
• a p-type nitride layer;
• an active layer;
• an n-type recovery layer;
• an n-type nitride layer;
• and
• an n electrode;
• wherein:
• the n-type nitride layer has a nitride polarity crystal and a gallium polarity crystal, and the surfaces of the nitride polarity and the gallium polarity regions appear different in height, the n-type recovery layer surface approximate to the n-type nitride layer has consistent mixed polarity with the n-type nitride layer, and the other surface far from the n-type nitride layer is a connected gallium polarity surface.

A fabrication method, comprising:

• 1) providing a substrate having an upper surface and a bottom surface opposite to each other, and nitriding a portion of the upper surface;
• 2) growing an n-type nitride layer having a nitride polarity crystal and a gallium polarity crystal on the upper surface of the substrate, wherein, the nitride polarity crystal is grown above the nitrided region of the substrate, and the surfaces of the nitride polarity and the gallium polarity regions appear different in height;
• 3) growing an n-type recovery layer on the n-type nitride layer, wherein, the upper surface is a connected gallium polarity surface;
• 4) growing an active layer and a p-type nitride layer in sequence on the n-type recovery layer, to form an LED epitaxial structure;
• 5) providing a conductive substrate, and connecting the conductive substrate to one side surface of the p-type nitride layer of the aforesaid LED epitaxial structure;
• and
• 6) removing the substrate of the LED epitaxial structure to expose the surface of the n-type nitride layer, and fabricating an n electrode thereon;
• wherein the fabricated LED epitaxial structure comprises:
• the substrate, having an upper surface and a bottom surface opposite to each other, wherein a portion of the upper surface is nitrided;
• the n-type nitride layer having a nitride polarity crystal and a gallium polarity crystal, formed on the upper surface of the substrate, wherein the nitride polarity crystal is grown over the nitrided portion of the substrate, and surfaces of the nitride polarity and the gallium polarity regions have different heights;
• the n-type recovery layer, formed over the n-type nitride layer, wherein the upper surface is a connected gallium polarity surface;
• the active layer, formed over the n-type recovery layer;
• and
• the p-type layer, formed over the active layer.