To provide a method for manufacturing a large-area semiconductor device, to provide a method for manufacturing a semiconductor device with high efficiency, and to provide a highly-reliable semiconductor device in the case of using a large-area substrate including an impurity element. A plurality of single crystal semiconductor substrates are concurrently processed to manufacture an SOI substrate, so that an area of a semiconductor device can be increased and a semiconductor device can be manufactured with improved efficiency. In specific, a series of processes is performed using a tray with which a plurality of semiconductor substrates can be concurrently processed. Here, the tray is provided with at least one depression for holding single crystal semiconductor substrates. Further, deterioration of characteristics of a manufactured semiconductor element is prevented by providing an insulating layer serving as a barrier layer against an impurity element which may affect characteristics of the semiconductor element.