A resin body is moulded around a die located on the front surface of a lead frame, and subsequently masking tape adhered to the rear surface of the lead frame is peeled away. While the tape is peeled away, the front surface of the lead frame is clamped by a surface which contains, or which can be deformed to contain, a recess for receiving the resin body. The peeling is performed by firstly separating an edge portion of the tape from the lead frame by a diagonal motion, and subsequently moving the edge portion across the lead frame so as to peel back the tape until its adhered surface faces away from the lead frame. A retrieval plate is urged against the adhered surface, so that the adhered surface becomes adhered to the retrieval plate. This process is repeated for successive lead frames, so that a stack of masking tape sections is formed on the retrieval plate.