The invention relates to a
gallium nitride based
light emitting diode chip and a preparation method thereof, and relates to a
semiconductor device provided with at least one
electric potential jumping barrier or a surface potential barrier and specially suitable for
light emission. The
gallium nitride based
light emitting diode chip is structurally characterized in that an epitaxial
wafer of a conventionally grown LED
epitaxy structure in the industry of
gallium nitride based
light emitting diode chips serves as a substrate, the substrate comprises a
sapphire substrate, a GaN buffer layer, a
Si doped n type GaN layer, an InGaN / GaN
multiple quantum well active area and a Mg doped p type GaN layer from bottom to top, then 1-6
layers of SiO2 / TiO2 distributed Bragg reflection structure
layers are alternately deposited, then a composite
metal Al film forms a reflected current
barrier layer, and an ITO transparent conducting layer in the industry of the
gallium nitride based light emitting
diode chips is assembled at last. According to the
gallium nitride based light emitting
diode chip and the preparation method, the
current crowding effect on a p
metal electrode in the prior art is eliminated, and the problem of LED chip luminous efficiency reduction due to the fact that the
metal electrode absorbs photons is resolved.