A method of fabricating a semiconductor package includes providing a lower semiconductor package including a lower package substrate, and a lower dummy ball and a lower solder ball on a top surface of the lower package substrate, providing an upper semiconductor package including an upper package substrate, and an upper dummy ball and an upper solder ball on a bottom surface of the upper package substrate, joining the upper dummy ball to the lower dummy ball at a first temperature to form a solder joint, and joining the upper solder ball to the lower solder ball at a second temperature to form a connection terminal.