A semiconductor package includes a film substrate; a wiring layer provided on the film substrate; and a semiconductor chip provided on the wiring layer and electrically connected to the wiring layer. The film substrate includes a first layer, wherein the first layer is an insulating layer having the wiring layer thereon. The film substrate further includes a second layer, wherein the second layer is attached to a bottom of the first layer and comprises a gas. The second layer is configured to be peeled off of the first layer.