Preparation method of total-reflection patterned substrate

The invention provides a preparation method of a total reflection patterned substrate. The preparation method comprises the following steps: S1, providing a cleaned sapphire substrate; s2, a first dielectric material layer is formed on the surface of the sapphire substrate, and the material of the first dielectric material layer is selected from A < l > N or Si < C >; s3, a second dielectric material layer is formed on the surface of the first dielectric material layer, and the refractive index of the second dielectric material layer is lower than that of the first dielectric material layer; s4, forming a photoresist layer on the surface of the second dielectric material layer, and opening an array pattern in a yellow light development mode; s5, performing transverse etching and longitudinal etching on the second dielectric material layer under the pattern by adopting I CP or Wetch i ng to form a patterned second dielectric material layer; and S6, removing the residual photoresist to obtain the total reflecti