| 摘要 |
PURPOSE:To ensure insulation between solder bumps, by forming electrode thin films on a semiconductor chip, spin coating photosensitive polyimide all over the surface, exposing only the electrode thin films by photoetching, vapor depositing a bump forming metal thereon and removing the polyimide film. CONSTITUTION:Electrode thin films 5 are formed on the surface of a chip formed on a silicon wafer. Photosensitive polyimide 6 is applied thereon by spin coating technique. After ultraviolet radiation is applied to the regions corresponding to the electrode thin films 5, the polyimide is developed to expose the electrode thin films only. A metal mask 7 having windows at the positions corresponding to the electrode thin films 5 is positioned thereon and indium 8 is vapor deposited. Removing the metal mask 7, there appear indium sections 8 connected by the polyimide 6 and arranged in matrix. The polyimide 6 is then peeled off and solder bumps of indium are obtained. Any indium 8 deposited on the polyimide 6 will be molten and removed together with the polyimide 6. Therefore, defect in insulation can be prevented completely.
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