Patent ID: 9690018
Date: 2017-06-27
CPC Classifications: B82Y,G02B,G03F,H01L

Claim:
1. A manufacturing method of a grating, the method comprising: forming a first photoresist film on a surface of a substrate; applying a second photoresist film on a surface of the first photoresist film away from the substrate; forming a plurality of first cavities in the second photoresist film by nanoimprinting the second photoresist film, wherein part of the first photoresist film is exposed through the plurality of first cavities to form a first exposed part; forming a plurality of second cavities by etching the first exposed part of the first photoresist film, wherein part of the surface of the substrate is exposed through the plurality of second cavities to form an exposed surface; depositing a mask layer on the second photoresist film and the exposed surface of the substrate; forming a patterned mask layer by removing the first photoresist film, the second photoresist film, and a portion of the mask layer deposited on the second photoresist film, wherein the patterned mask layer defines a plurality of third cavities, and part of the substrate is exposed through the plurality of third cavities to form a second exposed part; etching the second exposed part of the substrate through the patterned mask layer by reactive ion etching, wherein etching gases used in the reactive ion etching comprises carbon tetrafluoride, sulfur hexafluoride and argon; and removing the patterned mask layer.