Epitaxial structure of 940nm infrared LED and preparation method thereof

The invention provides an epitaxial structure of a 940nm infrared LED and a preparation method of the epitaxial structure, and belongs to the field of display equipment. The epitaxial structure sequentially comprises a substrate (1), a substrate buffer layer (2), a lower covering layer (3), a lower waveguide layer (4), a first active layer (5), a lattice buffer layer (6), a second active layer (7), an upper waveguide layer (8), a current limiting layer (9), an upper covering layer (10), a window layer (11) and an ohmic contact layer (12) from bottom to top. The first cover layer (3) comprisesa first cover layer (3-1) and a second cover layer (3-2). According to the invention, the lattice quality of the epitaxial structure can be improved, high-barrier electrons are provided, the mismatcheffect of a well barrier is reduced, the quality of an active layer well is improved, the luminous efficiency of a device is improved, the electron-hole recombination rate is improved, the luminous efficiency of the device is