Semiconductor device and a manufacturing method of the same

Abstract

By preparing a package substrate which has a plurality of lands of NSMD structure, and the output wiring and dummy wiring which were connected to each of the lands, and have been arranged mutually in the location of 180° symmetry, and printing solder by a printing method to the lands after the package assembly, the variation in the height of the solder coat between lands can be reduced, and improvement in the mountability of LGA (semiconductor device) is achieved.

1 - 15 . (canceled) 
     
     
         16 . A method of manufacturing a semiconductor device, comprising the steps of:
 (a) providing a wiring substrate having a main surface, a plurality of electrodes formed over the main surface, a back surface opposite to the main surface, an insulating film formed over the back surface, a plurality of lands formed over the back surface, and a first wiring and a second wiring connected to each land, wherein an edge part of each land is exposed from a corresponding opening of the insulating film, wherein the first and second wirings are arranged at locations substantially 180° from each other with respect to a perimeter of the land, and wherein a part of each of the first and the second wirings is exposed from the opening of the insulating film;   (b) mounting a semiconductor chip over the main surface of the wiring substrate through a die-bonding material;   (c) electrically connecting the semiconductor chip and the plurality of electrodes of the wiring substrate through a plurality of wires;   (d) sealing the semiconductor chip and the plurality of wires; and   (e) printing solder to the lands.   
     
     
         17 . A method of manufacturing a semiconductor device according to  claim 16 , wherein
 the plurality of lands constitute all of the lands formed over the back surface of the wiring substrate.   
     
     
         18 . A method of manufacturing a semiconductor device according to  claim 16 , wherein
 additional lands are formed over the back surface of the wiring substrate, and   the first and the second wirings are provided only for lands arranged in locations corresponding to an edge part of the main surface of the semiconductor chip.   
     
     
         19 . A method of manufacturing a semiconductor device according to  claim 16 , wherein
 the first and the second wirings are provided only for one or more lands arranged furthest from a center of the wiring substrate in plan view.