The present invention discloses a method for preparing an LED epitaxial
wafer, comprising: S1, providing a substrate; S2, growing a
nitride buffer layer on the substrate; S3, growing an undoped
nitride layer on the
nitride buffer layer; S4, growing an n-type nitride layer on the undoped nitride layer; S5, growing an
insertion layer unit on the n-type nitride layer, the
insertion layer unit comprising a pre-nitride
insertion layer, an
oxide insertion layer, and a post-nitride insertion layer grown in sequence; S6, growing a
quantum well light-emitting layer on the insertion layer unit; S7, growing a p-type layer on the
quantum well light-emitting layer. The method for preparing the LED epitaxial
wafer of the present invention decelerates electrons through the
high potential barrier of the
oxide insertion layer, buffers the injection of electrons into the light-emitting layer, reduces the recombination of electrons crossing the light-emitting layer with holes in the p-type layer, improves the droop effect under
high current, and at the same time, the
electron diffusion is more uniform after passing through the
oxide insertion layer, improves the uniformity of the
electron distribution in the light-emitting layer, increases the light-emitting efficiency, and improves the epitaxial optoelectronic uniformity and consistency.