Light-emitting diode and manufacturing method thereof

A light-emitting diode (LED) manufacturing method, comprising:

• providing a substrate, wherein the substrate comprises a top surface and a bottom surface, the top surface and the bottom surface being opposite to each other;
• forming a light-tight reflective layer on a top surface of the substrate;
• forming an epitaxial layer on a top surface of the light-tight reflective layer;
• removing a portion of a material of the epitaxial layer to expose the light-tight reflective layer, wherein the removed portion of the epitaxial layer forms a separation space, and the separation space splits the epitaxial layer into an inner epitaxial layer and an outer epitaxial layer, such that the outer epitaxial layer surrounds the inner epitaxial layer, wherein, in a view made from a top side of the LED, the separation space forms a closed path and surrounds a light exit hole, and, in a cross-section perpendicular to the closed path, an outside wall of the inner epitaxial layer, an inside wall of the outer epitaxial layer, and a portion of the top surface of the light-tight reflective layer jointly define an inverted trapezoid cross-section, two sides of the inverted trapezoid cross-section being respectively formed of the outside wall of the inner epitaxial layer and the inside wall of the outer epitaxial layer, a base of the inverted trapezoid cross-section being formed of the portion of the top surface of the light-tight reflective layer, an included angle between the outside wall of the inner epitaxial layer and a normal line of the top surface of the light-tight reflective layer being from 2 to 30 degrees, an included angle between the inside wall of the outer epitaxial layer and a normal line of the top surface of the light-tight reflective layer being from 2 to 30 degrees;
• forming a non-conducting layer, such that the non-conducting layer covers a top surface and the outside wall of the inner epitaxial layer and a top surface and the inside wall of the outer epitaxial layer, and also covers the top surface of the light-tight reflective layer between the inner epitaxial layer and the outer epitaxial layer, wherein the non-conducting layer comprises a light-transmitting material;
• removing a portion of a material of the non-conducting layer and forming an ohmic metallic body in the portion of the non-conducting layer from which the material is removed, so as to have the ohmic metallic body and the epitaxial layer electrically connected;
• forming a first electrode, such that the first electrode is electrically connected with the ohmic metallic body, and forming a light exit hole penetrating through the first electrode, wherein the first electrode is non-light-transmittable, and the light exit hole is located on a top of the LED, wherein, in a view made from a top side of the LED, the separation space forms a closed path and surrounds the light exit hole;
• and
• forming a second electrode, such that the second electrode is electrically connected with the inner epitaxial layer.