The invention relates to a reflecting type
grating light valve and a
processing method thereof. The reflecting type
grating light valve mainly comprises a
silicon substrate, a
silicon dioxide layer and removable
grating strips, wherein the
silicon dioxide layer is arranged on the silicon substrate, a plurality of removable grating strips are arranged on the
silicon dioxide layer, and the removable grating strips are mutually parallel and are also arranged in an equally spaced way; the removable grating strips are in a bridge shape with a suspended middle, and both ends of the removable grating strips are respectively fixed on the
silicon dioxide layer. The
processing method comprises the following steps that: the
silicon dioxide layer is grown on the silicon substrate, a silicon sacrifice layer is grown on the silicon dioxide layer, and a
silicon nitride layer is grown on the silicon sacrifice layer; the operation of
ion etching is carried out on the
silicon nitride layer by using an
ion etching method, and a silicon-
nitride beam part is remained; the operation of
erosion is carried out on the sacrifice layer by using a chemical
erosion method, the sacrifice layer is emptied, and a silicon-
nitride beam with a suspended middle is obtained, wherein both ends of the silicon-
nitride beam are fixed on the silicon dioxide layer; and the surface of the
silicon nitride layer is evaporated with a layer of
metallic aluminum or metallic silver as a
metal reflecting layer and an upper
electrode; the reflecting type
grating light valve has high light efficiency, high
extinction ratio and high response speed; and moreover, the reflecting type
grating light valve has a simple
processing process, can be used as a multi-path light modulating component of high-resolution
laser engraving equipment and is applied to the high-resolution
laser engraving equipment in the fields of high-quality printing and anti-counterfeiting packaging.