PURPOSE: To improve the noise margin of a sealed semiconductor chip by covering the upper surface of the resin sealing the chip with a shield plate which is integrated with an island connected to a grounding lead and drawn out from the sealing resin by bending the shield plate toward the sealing resin.

CONSTITUTION: A shield plate 2 integrally connected with the island 7 of a lead frame is provided and a semiconductor chip 5 is mounted on the island 7 with a mounting agent 6 in between. Then, after the chip 5 is electrically connected with a lead 1 and the island 7 is connected with a grounding lead, the chip 5 is sealed with a sealing resin 3 including the area of the island 7 except the area covered with the shield 2. Then the upper surface of the resin 3 is covered by bending the part of the shield 2 drawn out from the resin 3 toward the resin 3. Therefore, about 10-50% of external noise can be blocked and the noise radiated from the chip 5 can also be reduced.