超細(xì)間距 LED 顯示器芯片結(jié)構(gòu)和倒裝芯片 LED 無(wú)鉛焊膏的選擇

深圳市福英達(dá)工業(yè)技術(shù)有限公司/一站式錫膏解決方案供應(yīng)商Ultra-Fine-PitchLEDDisplayChipStructureandSelectionofLead-FreeSolderPasteforFlip-ChipLEDsWire-bondingLEDchips,verticalLEDchips,andflip-chipLEDsarethreedifferentstructuresofLEDchips.DifferentstructuresofLEDchipsinfluencetheselectionoflead-freesolderpastes.1.LEDChipDefinitionTheLEDchipisasemiconductordevicethatrealizesthephotoelectricconversionfunction.Itismadebyprocessingsemiconductorchipsonepitaxialwafers.Thissemiconductorchipfabricationprocessistotransfermetallicorganiccompoundstoahomogeneousorheterogeneoussubstrateatasuitabletemperatureandtogrowsemiconductorthinfilmmaterialswithspecificphotoelectricpropertiesthroughchemicalreactions.2.LEDChipLightingPrincipleEachpixeloftheLEDdisplayscreeniscomposedofasetofRGB(red,green,andblue)chips,whichbelongstotheself-luminousdisplaytechnology.RGBLEDluminescentmaterialsaredifferentaccordingtothevarioussizesofthebandgapsbetweentheconductionbandsandthevalencebandsofthematerials.Thus,theenergyreleasedisdifferentwhenthematerialsareexcited,whichisreflectedbythedifferentwavelengthsofelectromagneticwaves.Thehumaneyereceivesdifferentlightcolorsofelectromagneticwaveswithdifferentwavelengths.ThecorepartoftheLEDisthep-njunction.3.LEDChipStructureTherearethreemaintypesofLEDchipstructures:wire-bondingLEDchips,verticalLEDchips,andLEDflip-chips.Thewire-bondingLEDchipelectrodesareabovethelight-emittingsurface.ThecomponentsfromtoptobottomareP-GaN,light-emittinglayer(PNjunction),N-GaN,andsubstrate.TheverticalchipstructureadoptsSi,Ge,Cu,andothermaterialstoreplacethesapphiresubstrate,improvingheatdissipationefficiency.TheverticalLEDelectrodesareonbothsidesoftheLEDepitaxiallayertoavoidlocalcurrentcongestionandhightemperature.Flip-chipstructureconsistsofN-GaN,light-emittinglayer(PNjunction),P-GaN,metalelectrodes,andbumps.

Thewire-bondingstructuremainlyusesblue-greenLEDchips.TheverticalstructureappliesredLEDchips.Theflipchipissuitableforred,blue,andgreenLEDchips.

Forthepreviousfine-pitchLED(1.0mm≤Pitch≤2.5mm)packaging,wire-bondingblue-greenLEDchips,andverticalredLEDchipsareused.Withtheriseofmini-LEDandmicro-LEDandtheshrinkingofchipsizeandpixelpitch,thewire-bondingstructureislimitedbyspaceduetotheneedforb