LED ELEMENT AND MANUFACTURING METHOD FOR SAME

摘要

An LED element capable of further improving the light extraction efficiency and a manufacturing method for the same are provided.;In an LED element, a front surface of a sapphire substrate foams a verticalized moth eye surface having a plurality of depression parts or projection parts whose period is greater than twice an optical wavelength of light emitted from a light-emitting layer and smaller than coherent length, and a light whose intensity distribution is adjusted by reflecting on and transmitting through the verticalized moth eye surface to be inclined to a vertical direction with respect to an interface between a semiconductor lamination unit and the sapphire substrate is discharged from a transmission moth eye surface to an outer side of the element with Fresnel reflection being inhibited.

主权项

1. An LED element of a flip chip type, comprising:
a sapphire substrate; a semiconductor lamination unit that is formed on a front surface of the sapphire substrate and that includes a light-emitting layer; and a reflection unit that is formed on the semiconductor lamination unit, wherein the front surface of the sapphire substrate forms a verticalized moth eye surface having a plurality of depression parts or projection parts whose period is greater than twice an optical wavelength of light emitted from the light-emitting layer and smaller than coherent length, wherein a back surface of the sapphire substrate forms a transmission moth eye surface having depression parts or projection parts whose period is smaller than twice the optical wavelength of light emitted from the light-emitting layer, wherein the verticalized moth eye surface reflects and transmits light being incident on the verticalized moth eye surface from a side of the semiconductor lamination unit, and is configured in such a manner that, in an angle region exceeding a critical angle, intensity distribution of light emitted by reflection from the verticalized moth eye surface on the side of the semiconductor lamination unit is inclined to direction closer to vertical direction with respect to an interface between the semiconductor lamination unit and the sapphire substrate, as compared with the intensity distribution of light being incident on the verticalized moth eye surface on the side of the semiconductor lamination unit, and that, in the angle region exceeding the critical angle, the intensity distribution of light emitted by transmission from the verticalized moth eye surface on a side of the sapphire substrate is inclined to direction closer to the vertical direction with respect to the interface, as compared with the intensity distribution of light being incident on the verticalized moth eye surface on the side of the semiconductor lamination unit, and wherein the light, whose intensity distribution is adjusted by reflecting on and transmitting through the verticalized moth eye surface to be inclined to the vertical direction with respect to the interface, is discharged from the transmission moth eye surface to an outer side of the element with Fresnel reflection being inhibited.