| 摘要 |
PROBLEM TO BE SOLVED: To provide a photosensitive flux which does not require cleaning and removal of the residual flux after solder joining and filling, such as under- fill, maintains insulative property even in the atmosphere of high temp. and humidity and enables solder joining with high joining strength and reliability, and also provide a substrate for mounting semiconductor chips using the same, a semiconductor package and a printed circuit board. SOLUTION: This photosensitive flux enables the formation of via holes for solder joining in prescribed positions by exposure and development, is softened by subsequent heating and has the functions to develop adhesiveness and to fill the inside of the via holes for solder joining with a curable flux component. The photosensitive flux is formed on the substrate for mounting the semiconductor chips to be mounted with the semiconductor chips having solder bumps for mechanical and electrical connection and has the function to join, adhere and seal the semiconductor chips and the substrate for mounting the semiconductor chips by solder. |
