Jason Keeping, Celestica Dave Hillman Rockwell Collins ISCR 2016 IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Jason Keeping, Celestica Dave Hillman Rockwell Collins ISCR 2016

Agenda Background IPC Committee Task Plan Test Materials Test Vehicle Metallographic Sectioning Plan Conformal Coating Measurements Results To Date Looking At “Future”

Background Photo Credits: Left – Rockwell Collins, Right – NASA Card Guide tin plated Beryllium

Background Graphic Courtesy of CALCE Consortia

Background Graphic Courtesy of CALCE Consortia

Background Graphic Courtesy of CALCE Consortia

Background Graphic Courtesy of CALCE Consortia

Background Graphic Courtesy of PERM group

Background Cell Source: S. Meschter, “ReMAP Materials Project M2: High Temperature High Humidity Corrosion and Tin Whisker Evaluation of Bi containing Leadfree Alloys, SMTA ICSR Conference, 2016.

Background Cell Source: S. Meschter, “Strategic Environmental Research and Development Program (SERDP) Layered Nanoparticle Enhanced Conformal Coating for Whisker Mitigation, SMTA ICSR Conference, 2016.

IPC Conformal Coating Material & Application “State of the Industry” Assessment Project IPC-JSTD-001E Subcommittee Task Team: Conformal Coating Material & Application “State of the Industry” Assessment The goal of the project is to document the current “State of the Industry” of conformal coating application on printed wiring assemblies. The project will look at the major conformal coating types (i.e. AR, UR, ER, SR, XY) and method of application (i.e. spray, dip, brush). The project will not evaluate individual companies or specific conformal coating products – plan is to do a “blind” task activity. Study will produce baseline data on what thickness/coverage the industry is/can achieve with conformal coating materials.

Conformal Coating Types: AR = acrylic UR = urethane ER = epoxy IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Conformal Coating Types: AR = acrylic UR = urethane ER = epoxy SR = silicone XY = paraxylylene Application Method: Machine or Manual Spray Dip Brush Other Application Volunteers to collect and retain detailed documentation of application method –NO IP will be disclosed. Sufficient baseline application process details have been disclosed for every application method. Test Vehicle

Task Group coating/application tasks complete: IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Current Status: Task Group coating/application tasks complete: ~12 volunteer conformal coating facilities utilized ~ 95 individual test vehicles processed Application Method: Manual Spray: AR = 1, UR = 2, SR=3 Automated Spray: AR = 2, UR = 9, ER = 2, SR = 3 Vapor Deposition: XY = 1 Dip Deposition: AR = 1 Manual Brush: AR = 1 Manual Syringe/Automated Spray: AR =1 Cure Method: Heat “Thermal” UV Air/Heat/Humidity/UV combinations General: 3 Different Automated Spray Systems, Multiple Spray Angle/Pass Combinations

Processing: Photodocumentation IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Processing: Photodocumentation

Will “cap coat” gold layer for metallographic section purposes IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Coating Coverage and Thickness Assessment Method: Metallographic Cross-sectioning Details: Will gold sputter to define conformal coating outer edge before potting Will “cap coat” gold layer for metallographic section purposes Will cross-section from two angles Straight On Profile Lots of Photographs with general assessment before cross-section (photos, flat thickness measurement) Task Group Metallographic Process Document Available on IPC Kavi Site

3 Test Vehicles/Data Set, 25 Sections/TV IPC Conformal Coating Material & Application “State of the Industry” Assessment Project 3 Test Vehicles/Data Set, 25 Sections/TV Gold Sputtering/Protective Cap Layer

IPC Conformal Coating Material & Application “State of the Industry” Assessment Project

IPC Conformal Coating Material & Application “State of the Industry” Assessment Project

Measurements: Maximum, Minimum, and Top of Component Examples IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Measurements: Maximum, Minimum, and Top of Component Examples

Background: IPC Committee Test Task Summary: 2,028 cross sections, 3 years, 5 co-ops, Conservatively $350K in labor expenditures

Where are we today – All Done!: Cure Method: IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Where are we today – All Done!: Cure Method: Heat Cure: 10 of 10 Sets Completed UV Cure: 6 of 6 Sets Completed, Air Cure: 2 of 2 Sets Completed Air/Heat Combo: 6 of 6 Sets Completed Polymerized: 1 of 1 Set Completed Air/Humidity Combo: 1 of 1 Set Completed 21

Example Application Details: IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Example Application Details: SR Manually Sprayed with Binks Model 2001 conventional gun at angle (approximately 45 degree) with applications at every 90 degrees (the boards are rotated to receive the angle spray from 4 sides to prevent shadowing). UR Asymtek C740 equipment, SC300 atomizing head, 0.26 mm nozzle, 10 Degree flute, 10 psi fluid pressure, 30 psi atomizing pressure, 4 passes per path direction procedure. ER Atomized Spray Coating, 10 passes each in X & Y axis, IR Profile followed by Batch Cure 45 min, 1 - 3 mils.

Coating Type: Application: Cure Method: Air/Heat & Heat Cure 17 mils IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Coating Type: AR – Acrylic Only Application: M+A Spray, DIP, Brush Cure Method: Air/Heat & Heat Cure 17 mils Notes: 1) Lines (Green to Red) Manual Brush & Dip similar nominal thickness, but DIP higher coverage with more variability 2) Line (Blue) Has the lowest variation from the nominal thickness 23

Coating Type: Application: Auto & Man Spray Cure Method: IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Coating Type: UR – Urethane Only Application: Auto & Man Spray Cure Method: Heat, UV & Air/Heat Notes: 1) There are 3 nominal thicknesses 2) Lines (Green to Black) Air/Heat tracks UV; but slightly thinner 3) Lines (Red to Blue) Overall nominal thickness higher coverage higher 24

Coating Type: Application: Auto Spray Cure Method: 9.1 mils Heat IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Coating Type: UR – Urethane Only Application: Auto Spray Cure Method: Heat 9.1 mils Notes: 1) There are 3 nominal thicknesses 2) The (Green to others) nominal thickness along with coverage between the other two 3) Lines (Red to Blue) Nominal thickness is higher than the blue, but the coverage is lower 25

Coating Type: Application: Auto & Man Spray Cure Method: IPC Conformal Coating Material & Application “State of the Industry” Assessment Project Coating Type: SR – Silicone Only Application: Auto & Man Spray Cure Method: Heat, Air & Air/Humidity Notes: 1) The higher the nominal thickness; higher variation 2) Lines (Green to Purple) Auto-spray; air cure has higher variation then heat 26

How Does All of this Effort Pay-off? IPC Conformal Coating Material & Application “State of the Industry” Assessment Project How Does All of this Effort Pay-off? Provides a measure of industry conformal coating process benchmark for both OEM and Customer Provides both OEM and Customer a common dialogue starting point Provides tin whisker research community a basis for conformal coating/whisker testing 27

Questions ??? 28