The present invention relates to a semiconductor device and a manufacturing method thereof, particularly to a technology effective when applied to a semiconductor device in the form of a resin-sealed type semiconductor package and a manufacturing method thereof.
In semiconductor devices, a semiconductor chip is protected to keep its performance by sealing (packaging) the semiconductor chip with an insulating resin material or the like. For example, a semiconductor device is formed by attaching (mounting) a semiconductor chip having thereover an integrated circuit typified by a memory circuit, a logic circuit, a power circuit, or the like on the chip mounting portion (die pad) of a lead frame with a paste material and sealing a portion of the lead frame and the semiconductor chip with an insulating resin. In recent years, copper or copper alloy has been used as the material of the lead frame because it has high electric conductivity and heat conductivity and at the same time, low cost.
For example, Japanese Unexamined Patent Publication No. 2005-191178 (Patent Document 1) discloses a technology of forming, in a heat spreader, a dimple having an inwardly protruded sidewall and thereby improving adhesion with an insulating resin.
Japanese Unexamined Patent Publication No. Hei 5 (1993)-218275 (Patent Document 2) discloses a technology of forming dimples by press molding on a lead frame in order to improve adhesion with a sealing material and thereby eliminating the warp of the island.
Japanese Unexamined Patent Publication No. 2002-83917 (Patent Document 3) discloses a technology of actualizing a lead frame having high adhesion between a resin and a lead frame by etching a portion of the surface of the lead frame to form a plurality of protrusions selectively thereon.    [Patent Document 1] Japanese Unexamined Patent Publication No. 2005-191178    [Patent Document 2] Japanese Unexamined Patent Publication No. Hei 5 (1993)-218275    [Patent Document 3] Japanese Unexamined Patent Publication No. 2002-83917