Patent ID: 8865007

Claim:
A method for making a three-dimensional nano-structure array, comprising: providing a base; locating a mask layer on the base; patterning the mask layer to form a plurality of bar-shaped protruding structures on a surface of the base, wherein a slot is defined between each of two adjacent protruding structures of the plurality of protruding structures to expose a portion of the base; etching exposed portion of the base through the slot so that the each of two adjacent protruding structures begin to slant face to face until they are contacting each other to form a protruding pair, wherein the each of two adjacent protruding structures gradually slant and tops of the each of two adjacent protruding structures gradually approach each other, a first part of the base corresponding to each of the protruding pairs is etched at a first speed, and a second part of the base exposed from each of two adjacent protruding pairs are etched at a second speed, and the first speed is smaller than the second speed, and a plurality of first grooves and a plurality of second grooves are alternately arranged on the base, and a first depth of the first groove is different from a second depth of the second groove; and removing the mask layer.