Guidelines for Design, Selection and Application of ...

1 IPC-HDBK-830 AGuidelines for Design, Selection and Applicationof Conformal CoatingsDeveloped by the Conformal Coating Handbook Task Group (5-33c) ofthe Cleaning and Coating Committee (5-30) of IPCU sers of this standard are encouraged to participate in thedevelopment of future :IPC3000 Lakeside Drive, Suite 309 SBannockburn, Illinois60015-1219 Tel 847 847 Table of .. Units and Applications .. of Dimensions .. of Precedence .. and Definitions .. 22 APPLICABLE International Standards .. Aviation Regulations (FAR) .. Standards .. Industry Standard .. Standards .. Laboratories .. Standards .. Standards .. Standards .. Standards .. OSHA .. , Inc. Standards .. Standards .. Standards .. Global Standards .. Standards .. equipment Manufacturing (OEM)Specification .. Nature of MIL-I-46058 andIPC-CC-830 .. Relation of MIL-I-46058 andIPC-CC-830 to Performance Specifications.

2 103 environmental , HEALTH AND SAFETY(EHS) Exposure to Conformal CoatingMaterials/Ingredients .. Communication .. Employee Exposure Issues .. Safety Requirements .. Emissions / Permitting .. Waste Management .. Content Declaration (MCD)Regulations .. RoHS/WEEE/ELV .. ISPM15 Mark .. or Laws in Other Countries .. Content Declaration ReportingSystems .. Gas (GHG) Reporting .. Standards .. Mutual .. V S D .. 214 CONFORMAL COATING Types .. Acrylic .. Epoxy .. Silicone .. Polyurethane .. Parylene .. Cure .. Types of Conformal Coatings .. Fluoropolymer .. (FC) .. Layer Deposition Encapsulation(ALD-CAP) .. Coating Types and CC-830 .. Uses of Conformal Coating .. Selection of Conformal Coating .. Coating vs. Potting andEncapsulation .. Whisker Mitigation .. Mitigation .. Fungus Test Methods .. Mitigation .. Liquid Issues.

3 Film Flammability Concerns .. 325 DESIGN FOR COATING Philosophy .. Reliability Requirements .. the Product Life Cycle .. 32 August the Product Environment .. Applications .. Applications .. Density Interconnect (HDI) on PBs/Backplanes with Soldered or Press FitContacts .. Surfaces .. Surface Finishes .. Mask .. Material Type .. Components .. SMT .. SMT Components .. Voltage (HV)/High Current (HC) .. and Microwave .. Speed Digital .. Impedance .. Coverage .. To Be Coated .. When Coating Generally ShouldNOT Be Applied .. Coating for BGAs and SimilarComponents .. Coating Over Adhesives .. Considerations on Coating Coverage .. and Design Guidelines .. 446 RAW MATERIALS Properties .. Properties .. Properties .. with Process Materials .. Masks .. Residues .. Media .. Release Agent .. Masking .. of Inhibition .. of Inhibition.

4 Of Inhibition .. Check List .. Surface Energy .. Finishes .. Adhesion .. of Assessing Compatibility .. of Test Boards .. of Test Boards .. Assessment Techniques .. Environment .. Preparation .. Treatment .. Etching .. of Masks .. vs. Automated Masking .. Coverage .. Thickness .. Coating Thickness .. and Point Coverage .. Method .. Consideration .. Consideration .. Techniques .. Techniques .. Adjustment .. of Viscosity Adjustment .. 66 IPC-HDBK-830 AAugust of Viscosity .. Methods .. Spraying .. Spraying .. Coating .. Deposition .. Mechanisms .. Temperature Cure .. Cure .. Accelerable .. Cure .. Cure .. Cure .. Process Considerations .. By-Products .. Surface Cure/Solvent Entrapment .. Cure Recommendations .. Process Monitoring .. of Coating Thickness Measurements .. Guidelines .. Source .. Inspection.

5 , Health and SafetyProcessing Considerations .. Adjustment .. and Brushing .. Deposition .. 839 FILM .. Properties .. Withstanding Voltage (DWV) .. Resistance .. Constant and Dissipation Factor .. Properties .. Stability .. Shock .. Transition Temperature (Tg) .. of Thermal Expansion (CTE) .. Gradient .. Resistance .. Creep .. Stability .. Compatibility and ChemicalResistance .. Resistance .. Compatibility .. Resistance .. Resistance .. Resistance .. Stability .. Resistance .. and Ion Transport .. 8810 REWORK, REPAIR AND in the Factory .. and Repair in the Field .. and Restoration .. , Rework and Restoration Impact onReliability .. Coating Identification andRemoval .. Coating Identification .. Coating Removal Methods .. Blasting for Conformal CoatingRemoval .. Stripping for Conformal CoatingRemoval .. Removal of Conformal Coating.

6 Removal of ConformalCoating .. Removal .. Ablation .. Rework Methods .. Prior To Recoating .. of Conformal Coating .. Coating .. 102 August Considerations in Recoating .. , Health and SafetyRework and Repair Considerations .. 10311 END USE Environment .. (UV) Radiation .. Gases .. Rain .. and Coastal Environment .. Environment .. on the Ground .. Outside the Pressure Contain-ment Compartment During Operations .. Inside the Pressure Contain-ment Compartment During Operations .. Environment .. Environment .. Environment .. Biological Chemical WarfareEnvironment .. 10612 LONG TERM RELIABILITY AND Mechanism .. of Transparency/Discoloration .. of Adhesion .. Chemical Attack .. Testing .. Parameters .. of Tests .. UV Exposure Testing .. 109 APPENDIX AConformal Coating 110 APPENDIX BFlow Cup 113 APPENDIX CTroubleshooting 114 APPENDIX DThermal 118 APPENDIX ERelative 119 APPENDIX FTime of 120 APPENDIX GAtmospheric 121 APPENDIX HAirborne 123 APPENDIX ISimulated Acid Rain 127 APPENDIX JCoating for Medical 129 APPENDIX KExample of Stringent Test for AnyBreach in A Conformal 131 APPENDIX LTIN 132 APPENDIX MFUNGUS TEST 140 APPENDIX NHMIS CONTAINER 151 APPENDIX OGHS HAZARD SYMBOLS 154 APPENDIX PGHS SAFETY DATA SHEETS(SDSS) 154 APPENDIX QNPL 154 APPENDIX 1GC-MS Flux 177 FiguresFigure 3-1 GADSL and REACH SVHC Reportedin IMDS.

7 17 Figure 3-2 Recommendations Link .. 18 Figure 3-3 GADSL Reported on CAMDS .. 19 Figure 4-1 Conformal Coating Family Trees .. 23 Figure 4-2 Potential Loads During the Operation of anElectronic Assembly .. 27 Figure 4-3 Effects of 0 to 100% Relative Humidity onthe Operation of an Electronic Assembly .. 28 Figure 4-4 The K rner matrix showing the relation-ship between a material and the electricalinsulators made from it .. 29 Figure 5-1 Components which should not be coated .. 41 Figure 5-2 Connector interior should not be coated .. 41 Figure 5-3 Potentiometer s movable surface shouldnot be coated .. 41 Figure 5-4 Optical device which should not be coated .. 42 Figure 5-5 Components sensitive to CTE should notbe coated .. 42 Figure 5-6 BGA Cross Section and X-ray Images .. 42 Figure 5-7 Adhesive which will be conformal coated .. 43 Figure 5-8 Assembly Drawing with MaskingRequirements .. 44 Figure 7-1 0 rating The film immediatelydelaminates from the pressureused to cut through the film.

8 51 IPC-HDBK-830 AAugust 2013viiiFigure 7-2 1 rating The film does not delaminatefrom the pressure used to cut throughthe film. But, under slight pressurefrom the pick, the film delaminates .. 51 Figure 7-3 2 rating The film requires significantpressure to delaminate the film .. 51 Figure 7-4 3 rating The film can be plowed upwith the pick, but does not completelydelaminate ina continuous piece/film .. 51 Figure 7-5 4 rating The film cannot be removedwith the pick. The force required to movethe film typically damages the underlyingsubstrate .. 51 Figure 7-6 Dyne Pens .. 52 Figure 7-7 Cracked and Peeling Coated Areas .. 54 Figure 7-8 Critical Surface Tension Correction factoradd or subtract 4 dynes/cm for each 10%change in RH .. 54 Figure 7-9 The Effect of Surfactant Type on ConformalCoating Wetting .. 55 Figure 7-10 Measurements for Contact Angle .. 55 Figure 7-11 Goniometer (image courtesy of Rame HartInstrument Company).

9 56 Figure 8-1 Options of Cleaning Systems Accordingto Flux Type .. 59 Figure 8-2 Cure Windows of Primer Cure .. 61 Figure 8-3 Conditions that Influence the Extent ofPrimer Cure .. 61 Figure 8-4 Influence of Temperature and Humidity .. 61 Figure 8-5 Masking Tapes .. 63 Figure 8-6 Masking Boots .. 63 Figure 8-7 Spray Booth with a Manual Spray Gun .. 67 Figure 8-8 Nonatomized Curtain Coater .. 67 Figure 8-9 Swirl Applicator .. 68 Figure 8-10 Improvements in spray technology nowpermit pattern widths as tight as mm[125 mil] for work around sensitive keep-outareas .. 68 Figure 8-11 Conveyorized Applicator .. 68 Figure 8-12 Stand-Alone Batch Applicator .. 69 Figure 8-13 Automated Applicator .. 69 Figure 8-14 Dipping equipment with Smaller PCAs .. 70 Figure 8-15 Dipping equipment with Large PCAs .. 70 Figure 8-16 Vapor Deposition Polymerization Unit .. 71 Figure 8-17 Eddy Current Tool .. 76 Figure 8-18 Eddy Current System (Image courtesy ofHelmut-Fischer).

10 76 Figure 8-19 Example of an Eddy Current System(Image Courtesy of DeFelsko Corporation) .. 76 Figure 8-20 Taking a Reading with and Eddy CurrentTool (Image Courtesy of DeFelskoCorporation) .. 76 Figure 8-21 Measuring Conformal Coating with anEddy Current Tool (Image Courtesy ofDeFelsko Corporation) .. 76 Figure 8-22 Wet Film Comb (Image Courtesy ofNordson) .. 77 Figure 8-23 Measuring Wet Film (Image Courtesyof Gardco) .. 77 Figure 8-24 Wet Film Gauge .. 77 Figure 8-25 Ultrasonic Measurement System (ImageCourtesy of DeFelsko Corporation) .. 78 Figure 8-26 Taking a Measurement with an UltrasonicTool (Image Courtesy of DeFelskoCorporation) .. 78 Figure 8-27 Measuring Conformal Coating withan Ultrasonic Tool (Image Courtesyof DeFelsko Corporation) .. 78 Figure 8-28 Optical Measuring System (ImageCourtesy of Fritz Byle) .. 79 Figure 8-29 Image Refracting Through ConformalCoating (Image Courtesy of Fritz Byle) .. 79 Figure 8-30 Loss of Conformal Coating Adhesion.