UNDERFILLING MATERIAL FOR SEMICONDUCTOR PACKAGE

摘要

AN UNDERFILLING MATERIAL (5) FOR A SEMICONDUCTOR PACKAGE (2) HOLDING SEMICONDUCTOR ELEMENTS ON A CARRIER SUBSTRATE MOUNTED ON A CIRCUIT BOARD (3), CONTAINING A ONE-PACK TYPE THERMOSETTING URETHANE COMPOSITION WHICH PREFERABLY COMPRISES A URETHANE PREPOLYMER HAVING A TERMINAL ISOCYANATE GROUP, WHICH IS OBTAINED BY REACTING A POLYOL WITH AN EXCESSIVE AMOUNT OF A POLYISOCYANATE, AND A FINE POWDER-COATED CURING AGENT COMPRISING A CURING AGENT WHICH IS IN A SOLID STATE AT ROOM TEMPERATURE AND SURFACE ACTIVE SITES OF WHICH ARE COVERED WITH A FINE POWDER. THIS COMPOSITION CAN ACHIEVE BOTH THE LOW TEMPERATURE CURING PROPERTIES AND THE STROAGE STABILITY.