Method for manufacturing semiconductor device
In a double-sided electrode package, a sealing resin layer is formed so as to fill peripheries of surface-side terminals formed on a package substrate. Since the side surfaces of the surface-side terminals have plural protruded rims, adhesion with the sealing resin layer is improved by an anchor effect. At a sealing step, since supplied liquid resin is naturally flowed to form the sealing resin layer, a “mold step” and a “grinding step” may be omitted, and thus the sealing step may be simplified more greatly than a case where the resin sealing is carried out by a transfer molding method.
1. A method for manufacturing a semiconductor device, the method comprising:
a) forming electrode pads to be electrically connected to electrodes of semiconductor chips on a surface of a package substrate and forming external connection pads electrically connected to the electrode pads on a back surface of the package substrate;
b) laminating a metal film on the surface of the package substrate, forming a surface mask having a predetermined pattern on a surface of the metal film, the pattern being such that a plurality of pillar-shaped surface-side terminals, whose one ends are correspondingly electrically connected to the electrode pads, is formed on a peripheral portion on the surface of the package substrate, and etching the metal film to a predetermined depth using the surface mask to form pillar-shaped portions whose side surfaces are narrowed;
c) repeating:
i) a procedure for forming side surface masks for protecting the side surfaces of the pillar-shaped portions formed by etching; and
ii) a procedure for etching the metal film to a predetermined depth using the side surface masks and the surface masks so as to form the pillar-shaped portions whose side surfaces are narrowed,
until the package substrate is exposed, and
removing the surface mask and the side surface mask after the package substrate is exposed, to form pillar-shaped surface-side terminals having a plurality of protruded rims formed over entire peripheries of their side surfaces along a peripheral direction;
d) placing the semiconductor chips at a center of the surface of the package substrate and electrically connecting the electrodes to the electrode pads; and
e) coating the surface of the package substrate with liquid resin so that the other ends of the surface-side terminals are exposed and the semiconductor chips are coated to seal the semiconductor chips with the liquid resin.
2. The method for manufacturing a semiconductor device of claim 1 wherein, in e) the sealing of the semiconductor chips with the liquid resin, the surface of the liquid resin is in a position lower than the other ends of the surface-side terminals, and side surfaces of the surface-side terminals are coated with the liquid resin due to surface tension of the liquid resin.
3. The method for manufacturing a semiconductor device of claim 2 , wherein in e) the sealing of the semiconductor chips with the liquid resin, a partitioning member which holds up the liquid resin is arranged outside the peripheral portion on the surface of the package substrate so as to surround the peripheral portion, and after the partitioning member is arranged, the liquid resin is injected so as to cover the surface of the package substrate.
4. The method for manufacturing a semiconductor device of claim 2 , wherein in e) the sealing of the semiconductor chips with the liquid resin, the liquid resin is allowed to remain near and inside the plurality of pillar-shaped surface-side terminals arranged on the peripheral portion on the surface of the package substrate by means of surface tension of the liquid resin so as to cover the surface of the package substrate.
5. The method for manufacturing a semiconductor device of claim 1 , wherein in e) the sealing of the semiconductor chips with the liquid resin, a partitioning member which holds up the liquid resin is arranged outside the peripheral portion on the surface of the package substrate so as to surround the peripheral portion, and after the partitioning member is arranged, the liquid resin is injected so as to coat the surface of the package substrate.
6. The method for manufacturing a semiconductor device of claim 1 , wherein in e) the sealing of the semiconductor chips with the liquid resin, the liquid resin is allowed to remain near and inside the plurality of-pillar-shaped surface-side terminals arranged on the peripheral portion on the surface of the package substrate by means of surface tension of the liquid resin so as to cover the surface of the package substrate.
7. The method for manufacturing a semiconductor device of claim 1 , wherein in c), one end side of the surface-side terminals to be electrically connected to wirings is made thinner than the other end side.
8. The method for manufacturing a semiconductor device of claim 1 , wherein c) further includes providing a stepped portion to one end side of the surface-side terminals to be electrically connected to wirings.