资源描述:
《Novel Silicone Materials for LED Packaging》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、NovelSiliconeMaterialsforLEDPackagingAnnW.Norris*#,ManeeshBahadur*,MakotoYoshitake***DowCorningCorporation,P.O.Box994Midland,MI48686**DowCorningToray,Chiba,JapanABSTRACTSiliconebasedmaterialshaveattractedconsiderableattentionfromLightEmittingDiode(LED)manufacturersforuseasencapsulantsandl
2、ensesformanynextgenerationLEDdevicedesigns.Siliconescanfunctioninseveralrolesthatincludeprotectivelenses,stressrelievingencapsulants,mechanicalprotectionandlightpathmaterials.Thekeyattributesofsiliconesthatmakethemattractivematerialsforhighbrightness(HB)LEDsincludetheirhightransparencyint
3、heUV-visibleregion,controlledrefractiveindex(RI),stablethermo-mechanicalproperties,andtuneablehardnessfromsoftgelstohardresins.ThehighcurrentandhighoperatingtemperaturesofHB-LEDspresentasignificantmaterialschallengefortraditionalorganicmaterialssuchasepoxies,acrylicsandcycloolefincopolyme
4、rs(COC)thatlackthethermalandmolecularstabilityneededtoprovideopticalclarityandmechanicalperformancerequiredfornextgenerationdevices.Inaddition,theretentionofopticalclarityoverthelifetimeofthedevice,whichinvolveslongtermexposuretohighfluxintheUV-visiblewavelengthregion,isacriticalrequireme
5、nt.Siliconeshavebeendemonstratedtoprovidetherequiredstability.ThispaperwilldescriberecentsiliconematerialsdevelopmenteffortsdirectedtowardsprovidingLEDmanufacturerswithsiliconematerialssolutionsforLEDdevicefabrication.Injectionmoldingofnovelsiliconeresinbasedmaterialswillbediscussedasasur
6、mountablechallengeforhighthroughputLEDdevicemanufacturing.Keywords:Silicones,siloxanes,LEDs,lightemittingdiodes,encapsulants,lenses1.INTRODUCTIONAcurrenttrendinHBLEDpackagingmaterialsistheshiftfromorganicpolymerstosilicones.Thistrendisinaccordancewithfuturepackagingrequirements,asoutlined
7、byUSDepartmentofEnergy,theOptoelectronicsIndustry1DevelopmentAssociation,andtheNationalElectronicsManufacturersAssociationroadmaps.AtthesystemslevelmanufacturersarebeginningtospecifysiliconeencapsulantstotheirLEDsuppliers.Thereareanumberoffactorsthatarecontributingt