This invention relates to a semiconductor element and a manufacturing method, in which, the method includes: providing a photic base plate, forming a shading layer on it, forming a first buffer layer on the shading layer, forming a semiconductor layer on the first buffer layer, patternizing the shading layer, the first buffer layer and the semiconductor layer to form a patternized folded layer, forming a channel region and a source/drain region at both sides of the channel region, forming a grating insulation layer on the photic base plate to cover the patternized folded layer and forming a grid on the grating insulation layer above the channel region.