Dai Nippon Printing Co., Ltd.

Kouji Tomita

Chikao Ikenaga

Tsuyoshi Tsunoda

A frame for a semiconductor package has die-pads supported with suspending leads of individual lead frames. Semiconductor devices are arranged on the die-pads. These semiconductor devices are collectively molded with molding compound, and then the collectively molded semiconductor packages are cut into individual packages by means of a dicing saw. In the frame, suspending leads are formed into fish tails, wherein at least one of a longitudinal grid-lead and a transverse grid-lead is eliminated within areas enclosed with fish tails of the suspending leads. Accordingly, whether an R-shape generated by producing the frame by etching is large or small, the existence of metal pieces at the edges of the semiconductor packages is substantially prevented.

Frame for semiconductor package

A lead frame used for the production of a semiconductor package, wherein each of terminals of the lead frame to be wire-bonded to electrodes provided on the top surface of the semiconductor device has one or two groove(s) for limiting a plating area of noble metal. Since grooves are provided in each terminal, the accuracy of the plating area can be easily checked visually. Further, the grooves absorb stress applied to the terminal when the molded semiconductor packages are individually separated from each other by punching or dicing, and the situation where molding compound comes off of the terminal is prevented. In addition, since the grooves absorb vibrational stress applied to the terminal after mounting a semiconductor on the printed circuit board, the reliability of assembly is improved.

Lead frame and semiconductor package having a groove formed in the respective terminals for limiting a plating area

A frame for a semiconductor package includes plural lead frames arranged through grid-leads in a matrix. Semiconductor devices are mounted on individual lead frames of the frame, and are molded with molding compound. Thereafter, the molded semiconductor devices are cut at grid-leads by means of a dicing saw so that individual semiconductor packages are obtained. The frame further has groove portions which are formed by etching the frame from the front or back at areas corresponding to grid-leads, so that the grid-leads are made thin which reduces burrs and the generation of metal powders and dust.

A frame for semiconductor packages has die-pads supported with suspending leads of individual lead frames. Semiconductor devices are mounted on the respective die-pads. These semiconductor devices are collectively molded with molding compound, and then the collectively molded semiconductor packages are cut into individual packages by means of a dicing saw. In the frame, thin parts are formed in areas corresponding to the roots of individual terminals, the thin parts being formed by half-etching metal of the areas from the front or back thereof. Alternatively, hollows are formed in areas corresponding to the roots of individual terminals.

Frame for semiconductor package including plural lead frames having thin parts or hollows adjacent the terminal roots

A semiconductor package is comprised of a semiconductor device mounted on a die-pad , a wire for electrically connecting some electrodes of the semiconductor device and terminals of lead frame, wires for bonding the other electrodes of semiconductor device to the surface of die-pad for grounding, and molding compound for encapsulating the outer area of semiconductor device under a state where the back face of die-pad . The lower face and side face of terminals are exposed, wherein portions plated with silver for connecting of wires on the surface of the die-pad are formed at points positioned between a peripheral edge of the die-pad and an outer edge of the semiconductor device while leaving spaces from both the edges. The adhesion of die-pad to bonding compound is improved to avoid the occurrence of wires coming-off even if heat is applied to the contact points of die-pad to wires when mounting semiconductor package on a printed circuit board.

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Tokyo, Japan

Kouji Tomita