A surface mount semiconductor device having external contact elements exposed in a ball grid array (BGA) at its external active face for mechanical and electrical connection to an external support and a semiconductor die connected electrically internally with the external contact elements. A reinforcement layer of electrically insulating material extends between and surrounds laterally peripheral contact elements of the BGA. The reinforcement layer extends to from about thirty percent (30%) to about fifty percent (50%) of the height of the peripheral contact elements at the active face.