Abstract: A high-speed and high-performance semiconductor package reduces degradation of chip characteristics when chips are packaged. The semiconductor package includes a semiconductor chip including a plurality of bonding pads, a redistribution layer formed on the semiconductor chip while being connected with the bonding pads, a substrate attached to an upper surface of the semiconductor chip and formed with a window for exposing the redistribution layer, a connection member for electrically connecting the bonding pad of the semiconductor chip with the substrate, a sealing member for sealing the window including the connection member and a surface of the substrate including the semiconductor chip, solder balls attached to the substrate.