Detection method

The invention provides a detection method. The detection method comprises the steps of: sequentially forming a first insulating layer, a first gate layer and a first covering layer on a substrate, wherein the height of the first covering layer is determined according to a second covering layer on a second gate layer of a preset layer of a wafer to be detected, the first covering layer and the second covering layer are made of the same material, the first gate layer and the second gate layer of the preset layer are made of the same material, and a first through hole in the first covering layer and a second through hole in the second covering layer are obtained by etching with the same etching parameter; and determining the second gate layer in which the second through hole penetrates through the preset layer by penetrating through the first gate layer via the first through hole. The second gate layer of a preset layer of a to-be-tested wafer and the second covering layer on the second gate layer of the preset