Introduction to Probe Cards - SWTest.org

1 Integrated Technology CorporationCopyright 1998 IntroductiontoProbe CardsHow They are Built & Tested Integrated Technology CorporationCopyright 1998 Probe Cards & PROCESSCOURTESY OFCERPROBEI ntegrated Technology CorporationCopyright 1998 Design & LayoutIntegrated Technology CorporationCopyright 1998 DIE PAD CONFIGURATIONS 500 mils on each sideThese configurations typically use standard rings(1a)(1b)XYDM ulti-DU(1d)> 500 mils on any side(1c)These configurations typically requisemicustom or custom ringsFigure 1: Die and Ring Configuration ExamplesIntegrated Technology CorporationCopyright 1998 BONDING PADSABCBond PadMetalizationPassivationOpening(Bond Pad Size)Figure 2: Bond Pad Pitch and SizeIntegrated Technology CorporationCopyright 1998 CROSS SECTION, CANTALEVER BEAME poxyRing ApertureProbe Tip DepthPCB ApertureRingProbePCBPCB ottoSurfaProbe DetailsProbe WireDiameterTipLengthTip DiameterEpoxyClearanceEpoxyRingPlanarity HighestProbe LowestProbe E-tip (Radiused)FlatTip ShapeFigure 3: PCB and Epoxy Ring AssemblyIntegrated Technology CorporationCopyright 1998 EDGE SENSOR TYPES2-WireRight-Hand E/S2-WireLeft-Hand E/SIsolated 2-WireLeft-Hand E/SIsolated3-Wire EFigure 4.

2 Edge SensorsIntegrated Technology CorporationCopyright 1998 Probe TO PAD POSITIONINGBond PadMetalizationTotalScrubScrubProbe TipDiameterProbe Tip LocationAt TouchdownProbe Tip LocationAt Maximum OverdriveTarget (Pad Center)Passivation OpeningIntegrated Technology CorporationCopyright 1998 Probe FANOUT ANGLEF anoutAngleFanoutAngleRingProbesBond PadsIntegrated Technology CorporationCopyright 1998 Wire BendIntegrated Technology CorporationCopyright 1998 Wire Bend - Replacement ProbesIntegrated Technology CorporationCopyright 1998 Ring Build & FixtureIntegrated Technology CorporationCopyright 1998 Ring AssemblyIntegrated Technology CorporationCopyright 1998 Ring AssemblyIntegrated Technology CorporationCopyright 1998 Ring RemovalIntegrated Technology CorporationCopyright 1998 COMPLETED Probe RINGI ntegrated Technology CorporationCopyright 1998 Completed Probe RingIntegrated Technology CorporationCopyright 1998 Multi Layer Ceramic RingIntegrated Technology CorporationCopyright 1998 Measuring Contact ForceIntegrated Technology CorporationCopyright 1998 PCB CounterboreIntegrated Technology CorporationCopyright 1998 TrimmingIntegrated Technology CorporationCopyright 1998 Isolative

3 SleevingIntegrated Technology CorporationCopyright 1998 Probe AttachmentIntegrated Technology CorporationCopyright 1998 Probe card on Build PlateIntegrated Technology CorporationCopyright 1998 Probe card Sanding StationIntegrated Technology CorporationCopyright 1998 Alignment to WaferIntegrated Technology CorporationCopyright 1998 PlanarizationIntegrated Technology CorporationCopyright 1998 Finished Probe CardIntegrated Technology CorporationCopyright 1998 Multi-dut Probe CardIntegrated Technology CorporationCopyright 1998 Multi-dut Probe CardIntegrated Technology CorporationCopyright 1998 Multiple Probe LayersIntegrated Technology CorporationCopyright 1998 Cantilever Area ArrayIntegrated Technology CorporationCopyright 1998 Area Array (top)Integrated Technology CorporationCopyright 1998 Ceramic Blade Probe CardIntegrated Technology CorporationCopyright 1998 Building a Blade CardIntegrated Technology CorporationCopyright 1998 Cobra Probe CardIntegrated Technology CorporationCopyright 1998 Integrated Technology CorporationCopyright 1998 Cobra Probe cardIntegrated Technology CorporationCopyright 1998PB3000 Probe card ANALYZERI ntegrated Technology CorporationCopyright 1998 PROBILT PB3000 MOTHERBOARDI ntegrated Technology CorporationCopyright 1998 PURPOSE OF TESTINGnSCREEN TO SPECIFICATION LIMITSnESTABLISH SPCnESTABLISH LIFETIME GUIDELINESnESTABLISH REPAIR CYCLESnIDENTIFY POTENTIAL PROBLEMSnIDENTIFY POTENTIALIMPROVEMENTSI ntegrated Technology CorporationCopyright 1998 TEST PARAMETERSALIGNMENTTIPDIAMETERPLANARITYG RAMFORCECONTACTRESISTANCEEXTERNALCAPACIT OREXTERNALRESISTORLEAKAGECURRENTI ntegrated Technology CorporationCopyright 1998 ALIGNMENT &TIP DIAMETERnINSURE PAD CONTACTnINSURE NO PASSIVATION

4 DAMAGEnALLOW MAX. SET-UP TOLERANCEnAGING MONITORnLIMIT FORCE/UNIT AREAI ntegrated Technology CorporationCopyright 1998 ALIGNMENT TO PADTCTB1TB2 PASSIVATIONSAFETY AREAP1xP2xSCPCSXPI ntegrated Technology CorporationCopyright 1998 TIP DIAMETERnLIFETIME INDICATORn TRUE POSITION TOLERANCINGELIMINATES NEED FOR MAXIMUMLIMIT, EXCEPT FOR EOLnFORCE / UNIT AREAI ntegrated Technology CorporationCopyright 1998 PLANARIZATIONnINSURE GOOD CONTACTnLIMIT SCRUB LENGTH (BENDINGBEAMS)nCONTROL SCRUB DEPTHnLIMIT TIP FORCEI ntegrated Technology CorporationCopyright 1998 CONTACT RESISTANCEnLIMIT RMAX FOR DC PATHSnLIMIT SWITCHING TIME CONSTANTSnCHECK FOR CONTAMINATIONnCHECK PATH RESISTANCEnCR (W) TYP - 300 to 500 mOHMSnCR (BeCu) TYP - 100 TO 300 mOHMSI ntegrated Technology CorporationCopyright 1998 LEAKAGE CURRENTnADDS TO CIRCUIT LEAKAGEnDETECTION OF SHORTSnAFFECTS SWITCHING TIMESnGENERAL CONTAMINATIONDETECTIONI ntegrated Technology CorporationCopyright 1998 CONTACT FORCEnCONTACT RESISTANCEnSCRUB DEPTH CONTROLnFORCE PER UNIT AREAnGENERAL QUALITY CONTROLnAGING MONITORnPROBE GEOMETRY MONITORnPROBE RETENTION MONITORI ntegrated Technology CorporationCopyright 1998 COMPONENTSnVERIFY PRESENCE/ABSENCEnVERIFY COMPONENT VALUEnDETECT AGINGnDETECT OTHER CHANGESI ntegrated Technology CorporationCopyright 1998 PROBEROVERDRIVE REFERENCEnFIRST CONTACTnEDGE SENSORnPROFILERnVISUALM ichael George(408) 727-6500 x6244 Copyright 1998 Wafer ProbeEquipmentProberTest SystemInterfaceProbe CardWafer HandlingProductMetalized WafersMichael George(408) 727-6500 x6244 Copyright 1998 Probing :Checking for the Good & BadIn-Process (Parametric Testing).

5 When wafers are being built Checking for possible problemsAt the End (Etest, Sorting): When wafers are done Etest checks test patterns Process Parameters Sort identifies good/bad parts Functional Test Parametric Test Clock Speed, Temperature, George(408) 727-6500 x6244 Copyright 1998 Probe CardsShapes Square toRoundSizes 4 to 16 Probe Tips VariousMetalurgy,Types andSizesPROBE Probe CARDSCARDSM ichael George(408) 727-6500 x6244 Copyright 1998 Probe TipsTypes Cantilever Vertical MembraneSize .8 to 4 milsQuantity 10 to 2000 Materials Tungsten WR Paliney BeCuProbe CardProbe TipPROBE Probe CARDSCARDSM ichael George(408) 727-6500 x6244 Copyright 1998 Wafer Contact PointChips may have Different Contact PointsAl padsAu padsSolder bumpsTabs or TapeCritical ParametersAlignmentContact ResistancePad DamageMichael George(408) 727-6500 x6244 Copyright 1998 Probe Technology SelectionDependent on Contact Point TechnologyCantilever Beam ProbesPeripheral PadsAl or Au PadsSolder Bumps (Limited)Tabs or TapeVertical (Cobra)Array PatternsSolder Bumps (Flat Tips)Al or Au Pads (Pointed Tips)Michael George(408) 727-6500 x6244 Copyright 1998 Pretty Close !

6 !! Probe Probe CARDSCARDSQ: How close do we need to put the Probe in thepad?A: Within +/- 10 microns in x and y directionsQ: How small is a micron?A: If an inch was football field, a micron would be ablade of George(408) 727-6500 x6244 Copyright 1998 Types of TestersConfigured for Specific TechnologyMemory, uProcessor, Linear, Speeds >100 MHzRise Times <250 pSParallel Testing of Memory Devices (8-32 Chips)Every Interface is Different - NO STANDARDS!Test Head ConfigurationsDirect DockCabledMichael George(408) 727-6500 x6244 Copyright 1998 Test Head DockingCabled InterfaceDrive/Sense Electronics in Tester MainframeCables (COAX or Shielded Linear) to pogosTest Interface is only pogo pins to Probe CardSlower (Clock Rate) than Direct DockingDirect DockingDrive/Sense Electronics in Test HeadTest Head sits Directly on the InterfaceSoft or Hard Docking - Force/WeightHighest Speeds AvailableMichael George(408) 727-6500 x6244 Copyright 1998 Direct Docking to Tester (Courtesy Cerprobe Corporation)Michael George(408) 727-6500 x6244 Copyright 1998 Wafer HandlingLoading may be Manual or AutomaticManual LoadingUse Tweezer or Vacuum WandPossible Damage or BreakageCleanliness (Particles, Contamination)Very SlowAutomatic LoadingCassette Wafer HoldersOne or Multiple CassettesWafer Automatically Transferred to ChuckFaster, Cleaner, SaferMichael George(408) 727-6500 x6244 Copyright 1998 Wafer Alignment (1)

7 Align Probe Tips to PadsX,Y PositionTheta (Rotation)Overdrive (Z Axis)Manual AlignmentRotate Chuck/Wafer to be on Prober X,Y AxesRotate Probe card (if required)Position Probe Tips to Touch Down on PadsSet Overdrive to to mils (Type Dependent)Michael George(408) 727-6500 x6244 Copyright 1998 Wafer Alignment (2)Automatic AlignmentProber Aligns Wafer Using TargetsProbe card Theta not Usually RequiredWafer Loader Aligns Wafer from CassetteUpward Looking Camera to see Probe TipsDownward Looking Camera to see PadsCan Readjust Alignment During Probing