In some embodiments, the first enclosure 121 and the second enclosure 122 may include a thermal interface material (TIM), a phase change material (PCM) or an encapsulated PCM (ePCM). The above-mentioned materials may be mixed with the constituent materials of the first enclosure 121 and the second enclosure 122, may be coated on an inner face (the lower face BF in the case of the first enclosure 121, and the upper face UF in the case of the second enclosure 122) of the first enclosure 121 and the second enclosure 122 or on both faces, and may be manufactured from separate film or the like and attached to the inner face or both faces of the first enclosure 121 and the second enclosure 122. Such a thermal interface material or the like may help the first enclosure 121 and the second enclosure 122 to absorb, store or spread heat. The heat capacity of the enclosure assembly 120 and the memory device 100 including the same may be increased accordingly.

The materials of the first enclosure 121 and the second enclosure 122 may be the same or may be different from each other.

The first enclosure 121 and the second enclosure 122 may each include a lower face cover corresponding to the bottom face of the enclosure assembly 120. At least one of the first enclosure 121 and the second enclosure 122 may further include a side cover corresponding to the side face of the enclosure assembly 120. Although the illustrated first enclosure 121 includes a lower face cover and a plurality of side covers, the plurality of side covers may also be included in the second enclosure 122. Also, some side covers may be included in the first enclosure 121, and some other side covers may be included in the second enclosure 122.