Siliconware Precision Industries Co., Ltd.

Jen-Yi Tsai

Ying-Chou Tsai

Lien-Chi Chan

Ting-Ke Chai

Pao-Ho Yuan

A method of fabricating a FCBGA (Flip-Chip Ball-Grid-Array) package without causing mold flash is proposed, which is characterized by the forming of a dummy pad over the back surface of the substrate to allow the portion of the solder mask formed over a vent hole in the substrate to be substantially raised to an elevated flat surface where a groove is then formed to surround the exit of the vent hole. During a molding process, when the encapsulation material infiltrates to the exit of the vent hole, it can be confined within the groove in the elevated flat surface over the dummy pad, thereby preventing it from flashing to nearby solder-ball pads. Since there would substantially exist no mold flash over the exposed surface of the solder mask and the solder-ball pads, the proposed method allows the resulting FCBGA package to be assured in the quality of its outer appearance and the quality of the electrical bonding between the solder-ball pads and the subsequently attached solder balls thereon to make the encapsulated semiconductor chip reliable to use during operation.

Method of fabricating a flip-chip ball-grid-array package without causing mold flash

A flip-chip bumping technology is proposed, which provides a flip-chip bumping structure with dedicated test pads on semiconductor chip and method of fabricating the same. The proposed flip-chip bumping technology is characterized by the forming of a lined-array of electrically-conductive dual-pad blocks respectively over the internal I/O points of the semiconductor chip, each dual-pad block including a first pad and a second pad located beside and electrically connected to the first pad; and wherein the respective first and second pads of the dual-pad blocks-are alternately designated as bump pads and test pads. During testing procedure, the probing to the internal circuitry of the semiconductor chip is carried out through the test-pad portions of the dual-pad blocks, so that the probing needles would leave no scratches over the bumppad portions of the same. During subsequent bumping process, solder bumps are formed respectively over the bump-pad portions of the dual-pad blocks. Since the bump-pad portions of the dual-pad blocks would be left unscratched, it allows the solder bump attachment to be more assured in quality and reliability.

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Chiayi, Taiwan

Jen-Yi Tsai