Mounting process of semiconductor chip
Abstract
Abstract PURPOSE:To mount a semiconductor chip without collapsing by a method wherein bumps are formed of high melting point solder while subsolders on a semiconductor part are made of low melting point solder to make the subsolders reflow into the high melting point solder at the temperature not exceeding the melting point. CONSTITUTION:Bumps 5 are formed of high melting point solder, e.g., within the range of 270-312 deg.C on a part of Al wiring of a semiconductor chip 1 through the intermediary of a primary metallic film. On the other hand, a eutectic solder 8 in melting point of 183 deg.C is sub-soldered on a thick conductor part 7 formed on the surface of a ceramic substrate 6. Next, when the face down bumps 5 of chip 1 are overlapped on the subsolders 8 of semiconductor part to be aligned in contact with one another heated at around 200-230 deg.C for flip chip bonding, the subsolders 8 are melted to be fusion-welded into the bumps 5 but the bumps 5 are not to be melted thus hardly collapsing the chip 1. Through these procedures, the distance between the surface of chip 1 and the surface of substrate 6 can be controlled.
Inventors
- 👤 Yoshikiyo Usui
- 👤 吉清 臼井
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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