| 摘要 |
PURPOSE:To make it possible to perform sufficiently the bonding of fellow bump electrodes and to improve a bonding rate by a method wherein the second bump electrode, which is formed by making a soft metal coating coat on a copper electrode consisting of a hard metal and whose diameter is smaller than that of the first bump electrode, is made to bond to the first bump electrode consisting of a soft metal in such a way that the second bump electrode is bitten into the first bump electrode. CONSTITUTION:A first bump electrode 4a formed on a semiconductor chip 1 on one side is a cylindrical indium electrode 3 consisting of a soft metal, a second bump electrode 4b on a semiconductor chip 2 on the other side is one formed by making an indium coating 6 coat on a copper electrode 5 consisting of a hard metal and its diameter is made smaller than that of the electrode 3. Then, both chips 1 and 2 are made to oppose to each other and are aligned to each other in such a way that each bump electrode 4a and 4b is positioned at a prescribed position to correspond to each other. Then, these are heated and after that, the electrodes 4a and 4b corresponding to each other are pressed until they are deformed from a state that the electrodes 4a and 4b are coming into contact to each other into a state that the second bump electrode bites into the first bump electrode. Thereby, a thermocompression bonding, that is, the formation of bonding of the bump electrode is completed. |
