PURPOSE: To easily remove the moisture absorbed into a semiconductor device by a method wherein a hole part made in a resin sealed part is fixed by fitting a detachable cover formed of a different member to be engaged with this hole part.

CONSTITUTION: The airtightness of a hole part 8 made in a part of a resin sealed part 6 is maintained by a detachable cover 7 formed of different member to be engaged with the hole. It is recommended that the hole part 8 shall be made during the resin sealing step in terms of the correspondence with the metal molded structural surface. At this time, the absorbed moisture and condensated water content can be removed easily by making the hole part 8 in the depth reaching the tab 2 on the opposite side to the bond-fixing side onto an IC chip 1 and the tab 2. Furthermore, when said detachable cover 7 is removed and engaged with the hole part 8 again after drying up the semiconductor device at about 100°C for 1-10 hours, the water content can be removed so that the damage, crack, split, etc., of the semiconductor device due to the water content can be avoided. Accordingly, extra high dehydration and dehumidification effect can be achieved.