Patent ID: 8921133
Filing Date: 2014-12-30
Classification: B82Y,G02B,G03F,H01S

Abstract:
1. A method of forming a sampled grating, comprising the steps of: preparing a substrate; preparing a nano-imprinting mold including a pattern surface on which projections and recesses are periodically formed; preparing a mask including a light obstructing portion and a light transmitting portion that are alternately provided in a first direction; forming a photoresist layer and a resin portion in that order on the substrate; forming a patterned resin portion having projections and recesses by pressing the pattern surface of the mold into contact with the resin portion and hardening the resin portion while maintaining the contact, the projections and recesses formed on the resin portion being provided in a second direction; exposing a portion of the photoresist layer by irradiating the photoresist layer with an exposing light through the mask and the patterned resin portion; forming a patterned photoresist layer by developing the photoresist layer, the patterned photoresist layer including a pattern having projections and recesses formed on the portion of the photoresist layer; and etching the substrate using the patterned photoresist layer to form a first portion without a pattern having projections and recesses and second portion with a pattern having projections and recesses, wherein, in the step of exposing the portion of the photoresist layer, the photoresist layer includes a first area where the exposing light is obstructed by the light obstructing portion of the mask and a second area where the exposing light is transmitted through the light transmitting portion of the mask, and the second area of the photoresist layer is exposed to the exposing light that is transmitted through the recess in the resin portion, and wherein, in the step of etching the substrate, the first portion and the second portion are alternately formed, the first portion corresponding to a shape of the first area of the photoresist layer, the second portion corresponding to a shape of the second area of the photoresist layer.