Mems grating and fabrication method

A MEMS grating, comprising a substrate layer (1), an insulation layer (2) and a deformable layer (3), wherein the insulation layer (2) and the deformable layer (3) are arranged at an upper end of the substrate layer (1) in sequence, the deformable layer (3) is a conductive material with a compressive pre-stress, the insulation layer (2) is distributed along transverse intervals on the substrate layer (1), and a cavity (4) is formed between every two adjacent insulation layers (2);

• the deformable layer (3) comprises movable grating bars (5) and fixed grating bars (6), the fixed grating bars (6) are fixedly connected with the insulation layer (2), the movable grating bars (5) correspond to the cavities (4), included angles between the movable grating bars (5) and a side wall of the insulation layer (2) are each smaller than or equal to 90°, and the movable grating bars (5) are upwards-buckling camber surfaces;
• and
• a plurality of through holes (9) are formed in the movable grating bars (5) and used for adjusting a compressive pre-stress of the movable grating bars (5) and changing a displacement amount of upwards-buckling of the movable grating bars (5).