Method of bonding a chip part to a substrate using solder bumps
AssigneeFujitsu Limited
InventorsKatsuhiro Inoue, Nobuo Igusa, Takeshi Ohori
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Abstract
A method for bonding a chip part, having solder bumps on the underside thereof, to a base material. The method includes the steps of placing the chip part at a specific position on the base material, placing a weight on the chip part, the weight being based on the number of solder bumps mounted on the chip part and a surface tension of the solder bumps at melting, and irradiating, with an electromagnetic wave, an upper surface of the weight to transfer heat to the solder bumps through the weight and the chip, thereby melting the solder bumps and bonding the chip part to the base material.
Claims18
A method of bonding a chip part to a substrate using solder bumps, comprising the steps of:
- forming a chip part having an upper surface and a lower surface;
- placing said lower surface over said substrate with a predetermined number of solder bumps sandwiched between said lower surface and said substrate;
- putting a weight of a heat absorbent material on the upper surface of said chip part, said weight being based on both the predetermined number of said solder bumps and a degree of surface tension of each of the solder bumps in a molten state;
- irradiating electromagnetic waves to said weight to heat said weight, which heats said chip and heats said solder bumps to a molten state;
- and
- during said irradiating step, maintaining a fixed amount of pressure on said chip part by said weight.
Dependencies are inferred from the claim text.