Abstract
Thispaperisconcernedwithbondingstrengthoftheadhesivetapecomposedofanacryliccopolymer,mixedepoxyresinsanddipentaorithrytolhexaacrylate(DPHA),whichisapplicabletodicinganddiebondingthereafter.Investigatedweretheeffectsoftheexposuredoseofultra-violetlight(UV)beforedicingandtheamountsofDPHAonthebondingstrengthbetweenthermallycuredadhesivecompoundandthecoppersubstrateasthemodelfoi､oil℃uits･IncaseswhereeitheroftheexposureandDPHAwaswithin400mJ/cm-or10partsofothercomponents.respectively,the90peelstrengthwasstrongenoughexceeding6N/cm.ThestoragemodulusatiOU℃,theinitialbondingtemperature,wasbelow4x10'Paevenforthecasesofpooradhesion,indicatingenoughwettabilitytothesubstrate.However,theX-rayphotoelectronspectrometry(XPS)takenatatake-offangleof45ontheinterfacelayerofadhesivesprovedthattheoxygen/carbonatomicratio(O/C)was0.36beforeUVexposureandthendecreasedto0.27uponexposureto780mJ/cm-resultinginverypooradhesion.ThetendencyofdecrementofoxygenatomsintheinterfacewasalsoobservedinthecaseofhigherDPHAcontentthan10parts.Itwasthereforeconcludedthatthebondingstrengthlargelydependsonthechangeindistributionofoxygenatomsorpolargroupsintheinterfacelayet･duringUVcuringofDPHA.
