Advanced Material Selection

Advanced Material SelectionIPC Designers CouncilMichael J. GayFebruary 8th 2017Michael.gay@isola-group.com

Laminate Material Components

Resin, Glass, CopperResinPrepreg or B-StageGlassCopperB-Stage Foil Laminate

Glass Fabric - Yarn

Glass YarnCritical Differences Composition effects Finished glassyarn bobbinsElectrical propertiesMechanical propertiesPCB process-abilityCost – 1 to 10xAvailability may belimited

Glass Yarn Properties Composition determines the effects of glass on thecompositeLow glass CTE values increasethe gap between othercomponents of the composite

Glass Composition Decision TreeE-glassorLDk glassLow Dk glass Lower Dk & Df Increases glass cost 5-6x Increases lead timeE-glass(Standard) Standard Dk & Df Low cost Readily available

Glass Fabric – Weaving

Fabric Weaving Process

Glass Fabric TypesLess Skew or Fiber Weave Effect Spread (MS) weaves reduce the Fiber Weave Effect (FWE) Spread or expanded must be in both directions

Two Main Fiber Weave EffectsHigh Er;Low ZoLow Er;High Zo1. Effects due to locationof trace with respect tofiber weave bundles2. Effects due to periodicloading of trace byfiber weave bundles –resonanceФ

Ultra Thin Glass

Open vs Spread Weave1080Warp & Fill Count: 60 x 47 (ends/in)Thickness: 0.0021” / 0.064 mm1086Warp & Fill Count: 60 x 60 (ends/in)Thickness: 0.0022” / 0.050 mmPhotos courtesy of Isola R & D Laboratories

Glass Weave Decision TreeOpenor MSSpreadMechanicallySpread Weave Reduces FWE(Fiber Weave Effect) Increases glass cost 1.2-1.4x Improves dimensional stability Improves thickness controlOpenWeave Low cost Notable FWE(Fiber Weave Effect) Readily available Through glass resin flow

Glass Fabric - Style

Glass Styles*****Square Weave*E-glass and Low Dk glass nominal weights are not equal

Glass Style Decision TreeSquareor UnbalancedSquareWeave Reduces FWE(Fiber Weave Effect) Increases glass cost slightly Improves dimensionalstabilityUnbalancedWeave Low cost Notable FWE(Fiber Weave Effect) Variation in x-yperiodicity

Guide to Selecting Glass

Resin

Resin Technology Base Resin Components Difunctional & Tetrafuntional Polymers, OligomersDicy, Phenolic, Novel curingBlends Polyphenylene oxide PPO/Epoxy Bismaleimide Triazine (BT)/Epoxy“I have discovered something Cyanate Ester/Epoxynovel that will change the way Polyphenylene ether PPE/Epoxywe make laminates!”Polyimide, Hydrocarbon, Teflon, Acrylic,Melamine,Next generation of non-PTFELiquid Crystal Polymerslaminate is expected to haveProprietary Thermoset Polymers andDk 3.0 DkPolymer blendsDf 0.001

Resin Technology Fillers - ‘Components’which influence the electricalproperties and thermalperformance Various types of SilicaAluminum SilicateTalc (usage in laminate is patented)RubberGlass microspheresBoron Nitride – Thermal managementSize and shape effect

Resin Technology Flame retardants Brominated – TBBPATetrabromobisphenol-A Halogen Free Phosphorus based Aluminum hydroxide Magnesium hydroxide Nitrogen based Solid vs reacted

Mixing & Blending llersFlameRetardantsFiltration Woven filters – removecontaminants in liquid components Magnetic Filters – remove ferrouscontaminates High Shear Milling/Mixing –ensures homogenous mixing of allcomponents and sizes fillers Viscosity measurement andfeedbackTo the TreaterHigh ShearMilling/MixerViscosityRegulator

Comparing Resin SystemsAttenuation (dB/in) vs Frequency (GHz)Ultra LowLossVery LowLossVery LowLossVery LowLossLow LossMid LossMid LossUltra LowLossVery LowLossLow LossStandard LossCourtesy of Speeding EdgeMid Loss

Material Loss PyramidUltra Low Loss materials arebecoming the main focus for futureHSD designsCurrent Halogen Free CeilingUltra Low LossDf 0.0032Tier 5MaterialsDf 0.0032 0.005Very Low LossTier 4MaterialsLow Loss Df 0.005 0.01Low LossTier 3MaterialsMid Loss Df 0.01 0.02Tier 2Standard Hi Tg FR4 Df 0.02Tier 1Approximately 400 material offerings available todayStandardMaterials

Resin Decision TreeDielectricPropertiesDk 4.0Dk 3.5-4.0Dk 3.0-3.5Dk 3.0E-Glass withstandard lossresinE-Glass withmid/low lossresinLDk Glasswith ultra/verylow loss resinTeflon E Glass& LDk GlassDf 0.25Df 0.007Df 0.002Df 0.002Where Dk is lower, Df tends to be slightly lower

Glass Impregnation

Treating Technology FiltrationMagnetic barsTension controlsPre-dipOptimized primary dipReversing metering rollsAutomated inspection

Finished B-StageB-stage material to beused as prepregB-stage material to beused to make laminate

Copper

Copper Foil Plating ED Copper Grain Structure determines: Surface roughness or profile Physical properties of the copper Almost No Profile (ANP) – 2 µm Minimum thickness with carrier - 2,3, 5 µmWarning: Copper is sold to the laminatorby weight Oz. not by thickness. Copper thickness is specifiedin mils for PCB’s PCB processing reducescopper thickness Oz. Mils

Copper Foil TreatmentFoil Treatment Baths Barrier layer treatment Transition layer Treatment/coating maybespecific to a resin systemMatte/Prepreg SideReverse Treated CopperDrum/Laminate SideChromateZincCopper NodulesNickel/ZincChromateSilane Secondary plating – Nodulation Reduction of conductor losses Minimization of conductor path

Copper Surface Images Smoother copper results in reduced conductorlossesCourtesy Mitsui Copper Foil

Skin EffectCourtesy Mitsui Copper Foil Skin depth decreases as frequency increases Conductor losses decrease as foil roughness decrease

Copper Foil Decision TreeCopper FoilSurfaceRTF/HTEVLP 5-6 um 2-3 um Standard Availability Standard Availability Low Cost Increased Cu Cost 1.5x Reduced Cu lossNP/ANP 2 umIncreased lead timeIncreased Cu cost 5-10xBest for conductor lossReduces conductor loss component

Inner Layer Bonding Treatment(during PCB processing)Cleanedcopper surfaceBondingtreatmentCourtesy Oak MitsuiWarning:Not all surface treatments are equal andresult in significant variation from fab shopto fab shop

Lamination

LaminationLay up Copper foilapplied to bstageLaminate KitBuild up –Kits builtinto a bookMaster sheetlamination

Finished ProductsPrepregCopper Clad Laminate

PCB Material Performance Needs PCB process ease and compatibility Thermal performance during PCB fabrication andassembly Sequential lamination Assembly cycles Rework and localized performance Design appropriate dielectric properties Long term reliability Low cost to performance ratio

Selecting the Right Material Laminate material selection can not be condensedinto a single page chart (Data sheet) for easyselection. More information is needed Cost-to-performance evaluations must be done bythe system design team to ensure selection of thelowest cost material that is good enough Collaboration between laminate material suppliers,key PCB fabricators and the OEM designer isimportant to achieve peak price/performance results

Laminate Material Processing Cost Considerations Lamination cycle 60-90 minute cure Temperature Drill tool cost Hit count Special BU and/or Entry Desmear processing Plasma Chemical Baking requirements When and how long? Special processing

Laminate Thermal Performance Fabrication processing Multiple lamination 8-10 cycles Lead Free HASL Multiple baking steps Assembly processing Multiple reflow cyclesRework processingMinimal moisture uptakeHDI Compatible – Stacked micro vias on blind

Laminate Material Capability There is no one singleTest Vehicle to learneverything, but we canlearn a lot from them MRT6 Industry TV Thermal performanceCAF performanceElectrical performanceIST performanceCycling performance Others – not publicTV created by members of HDPUG

Laminate Electrical PropertiesBasic Categories Dielectric Constant Dk Standard Dk 4.0 Mid Dk: 3.5 – 4.0 Low Dk: 3.0 – 3.5 Ultra Low: 3.0 Dissipation Factor Df Ultra Low Loss Df 0.0032 Very Low Loss Df: 0.032 – 0.005 Low Loss Df: 0.005 – 0.007 Mid Loss Df: 0.010 – 0.02 Standard Df 0.020 Conductor losses of copper foil RTF VLP NP/ANP

Data Sheet Laminate Properties Laminate properties are tested across a range of resincontents, frequencies, constructions, using appropriate‘laminate / dielectric’ test methods Laminate Dk and Df values at 1 MHz and 1 GHz alone donot provide sufficient data for designers for High-speedDigital applications Laminate data sheets provide ‘single points’ ofinformation for Dk and Df based on a single resin content(usually 40-60% RC range)

Typical Laminate Comstruction Data

Typical Industry SI Test Vehicles

Comparing Resin SystemsAttenuation (dB/in) vs Frequency (GHz)Ultra LowLossVery LowLossVery LowLossVery LowLossLow LossMid LossMid LossUltra LowLossVery LowLossLow LossStandard LossCourtesy of Speeding EdgeMid Loss

Selection Summary Select a material with proven SI & thermal performance on an industry accepted or internal TVCollect the laminate Dk/Df data for the construction setand properties that fit your design criteriaConsider glass type and how it influences your designConsider copper type and how it influences your designEvaluate hybrid construction opportunitiesCompare major processing steps for hidden costEvaluate cost to performance of material options

Laminate Cost

CONTACT INFORMATIONCorporate Headquarters3100 West Ray Road, Suite 301Chandler, AZ 85226480-893-6527800-537-7656Fax 480-893-1409info@isola-group.comAsia Pacific Regional HeadquartersUnit 3512 - 3522, 35/FNo. 1 Hung To Road, Kwun Tong,Kowloon, Hong KongPhone: 852-2418-1318Fax: 852-2418-1533info.hkg@isola-group.comEuropean Regional HeadquartersIsola Strasse 2D-52348 Düren, GermanyPhone: 49-2421-8080Fax: 49-2421-808164info-dur@isola-group.comMichael J. GayMichael.gay@isola-group.comPhone: (503) 713-7965For permission to reproduce any portion of these materials, please contact the presenter.Isola, GETEK, I-Fill, I-Speed, I-Tera, Ultra-EC25, Green Speed, Astra, Gigasync, Tachyon, Stratus, Terragreen, IsoDesign, IsoStack, Polyclad, DSTF, Duraver, Chronon and the Isola logo areregistered trademarks of ISOLA USA Corp. in the U.S.A. and other countries. All other trademarks mentioned herein are property of their respective companies.Isola has made commercially reasonable efforts to ensure information in these materials is accurate and up to date. The information may contain inadvertent errors, or be supersededby updates. The information is provided on an AS IS basis, without any representations or warranties, express or implied. No licenses are conveyed, implicitly or otherwise, under anyintellectual property rights. The sale of Isola products is governed by Isola’s terms and conditions of sale. The information in these materials does not change or alter such terms.

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intellectual property rights. The sale of Isola products is governed by Isola’s terms and conditions of sale. The information in these materials does not change or alter such terms. Corporate Headquarters 3100 West Ray Road, Suite 301 Chandler, AZ 85226 480-893-6527 800-537-7656 Fax 480-893-1409 info@isola-group.com