Abstract: This invention relates to the thermosetting resin compositions useful for mounting onto a circuit board semiconductor devices, such as chip size or chip scale packages (“CSPs”), ball grid arrays (“BGAs”), land grid arrays (“LGAs”) and the like, each of which having a semiconductor chip, such as large scale integration (“LSI”), on a carrier substrate. Similarly, the compositions are useful for mounting onto circuit board semiconductor chips themselves. Reaction products of the compositions of this invention are controllably reworkable when subjected to appropriate conditions. And significantly, unlike many commercial rapid curing underfill sealants (“snap cure underfills”), the inventive compositions possess an exotherm under 300 J/g or demonstrate package stability at 55° C. for 7 days, and therefore do not require special packaging to be transported by air courier, or special approval from international transportation authorities, such as the U.S. Department of Transportation, to permit such air transport.

Abstract: This invention relates to the thermosetting resin compositions useful for mounting onto a circuit board semiconductor devices, such as chip size or chip scale packages (“CSPs”), ball grid arrays (“BGAs”), land grid arrays (“LGAs”) and the like, each of which having a semiconductor chip, such as large scale integration (“LSI”), on a carrier substrate. Similarly, the compositions are useful for mounting onto circuit board semiconductor chips themselves. Reaction products of the compositions of this invention are controllably reworkable when subjected to appropriate conditions. And significantly, unlike many commercial rapid curing underfill sealants (“snap cure underfills”), the inventive compositions possess an exotherm under 300 J/g or demonstrate package stability at 55° C. for 7 days, and therefore do not require special packaging to be transported by air courier, or special approval from international transportation authorities, such as the U.S. Department of Transportation, to permit such air transport.