Structure of broadband wave absorber and preparation method

The invention provides a structure of a broadband wave absorber and a preparation method. The structure comprises a substrate layer and a half-pyramid structure arranged on the substrate layer, wherein the half-pyramid structure is formed by alternately stacking and combining multiple metal-medium layers, the size of the structure is decreased progressively from bottom to top in the Z direction, the structure is a symmetrical structure, and the axis of symmetrical is a connecting line of centers of the metal-medium layers. A substrate is coated with the metal-medium layers sequentially with a coating method, and then the half-pyramid structure is etched. The structure is simple: the structure of the wave absorber is single and convenient to prepare. The spectrum is easy to measure: at the measurement stage, the band ranging from 8 mu m to 14 mu m is a middle infrared band, and the transmission and reflection spectrum of the structure can be acquired easily by the aid of existing equipment, so that the absorption spectrum is acquired.