Method for reducing warpage occurred to substrate during packaging process

A method for reducing warpage occurred to a substrate during a packaging process, comprising:

• attaching a plurality of dies to an upper surface of the substrate;
• attaching an adhesive material to a lower surface of the substrate, wherein the adhesive material has a first curing temperature;
• heating a molding material to a molding temperature and applying the molding material to surroundings of the dies, wherein the molding material has a third curing temperature;
• heating the substrate, the adhesive material, and the molding material to a heating temperature not less than the first curing temperature and the third curing temperature;
• and
• cooling the substrate, the adhesive material, and the molding material to a room temperature;
• wherein when being cooled to the room temperature, the molding material applies an upper-surface shrinkage stress to the upper surface of the substrate, the adhesive material applies a lower-surface shrinkage stress to the lower surface of the substrate, and the lower-surface shrinkage stress is substantially equal to the upper-surface shrinkage stress.