| 摘要 |
PROBLEM TO BE SOLVED: To provide a sheet for transferring a ball which can hold certainly a metal ball on the sheet so that the ball may not drop or move from the sheet in an inspection, in loading to an electrode or in the case of movement, moreover, which can store, which can be immediately acted for loading of the ball to the electrode top of an electronic circuit for a user without conducting the ball loading and the inspection to the sheet, and which is easy to use for the user; and to provide a method of transferring the ball and a method of forming a bump by utilizing the same. SOLUTION: The sheet for transferring the ball includes a release layer 7 provided in the one side of the sheet 2 and being as mold release characteristics, a hole 8 in which an adhesion layer 5 exposed to the bottom which holds the metal ball on the surface in the same pattern as the electrode, and a water soluble film 3 containing a flux component which is melted or softened when heated, though it is a solid state at the normal temperature from above it, after the metal ball 1 is contained in the hole. When this sheet is heated under pressure by opposing the ball to the electrode and the film is melted and cooled, the ball is transferred to the electrode. Then, when the reflow heating is performed to melt the ball, the bump is formed on the electrode. Finally, it is washed, and the film can be removed. COPYRIGHT: (C)2005,JPO&NCIPI
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