Patent ID: 7785986

Claim:
A method of manufacturing a semiconductor device, comprising steps of: (a) forming an element and a wiring layer on a main surface of a semiconductor wafer; (b) reducing a thickness of the semiconductor wafer; (c) cutting out semiconductor chips from the semiconductor wafer; and (d) transporting the semiconductor chips in a state that the semiconductor chips are accommodated in a tray, wherein the step (d) includes the steps of: (d1) providing a plurality of trays each having a first accommodating portion formed on a main surface thereof and a second accommodating portion formed on a back surface thereof, the back surface thereof opposing to the main surface thereof; and (d2) transporting the plurality of trays to a desired place in a state that the semiconductor chips formed in the step (c) are accommodated in a space, wherein the space is defined at portions where the second accommodating portion of the back surface of an upper-stage tray of the plurality of trays overlaps the first accommodating portion of the main surface of a lower-stage tray of the plurality of trays, when the plurality of trays are stacked in a plurality of stages; wherein a projection is formed on a bottom surface in the second accommodating portion, the bottom surface opposing to the semiconductor chip; wherein the projection is not in contact with the semiconductor chip accommodated in the tray; wherein the semiconductor chip is accommodated such that a main surface of the semiconductor chip opposes to the bottom surface of the second accommodating portion; wherein a polyimide-based resin film is exposed on the main surface of the semiconductor chip; and wherein an external terminal formed on the main surface of the semiconductor chip is exposed from an opening formed in the resin film.