The manufacturing method includes attaching a single crystal semiconductor layer to a supporting substrate, detecting a position of a deficiency region in the single crystal semiconductor layer, forming a non-single-crystal semiconductor layer over the single crystal semiconductor layer, selectively improving crystallinity of a portion of the non-single-crystal semiconductor layer based on the position of the deficiency region, the portion being overlapped with the deficiency region, and planarizing the non-single-crystal semiconductor layer over the supporting substrate.