pcb laminates 101

PCB LaminatesWhat you need to know!

What Is It?

Components•Core•Pre-Preg•Foil

Vendor Datasheet• Thickness• Glass Weave

What Is It?

• Fiberglass Reinforced Epoxy

High Speed vs. Glass Weave

The “Players”

• USA

• Asia

The “Choices”

*Isola’s Product Ladder

The “Choices”

• FR-4 - Flame Retardant Class 4

• DICY Epoxy

• Modified DICY Epoxy

• Fillers

• Low Loss

• Halogen-Free

• Others

• PTFE, LCP, Polyamide, CEM

Properties

• Tg - Glass Transition Temperature

• Td - Decomposition Temperature

• CTE - Coefficient of Thermal Expansion

• Dk - Dielectric Constant

• Df - Dissipation Factor

• Moisture Absorption

• Flammability

• Anti-CAF - Conductive Anodic Filament

Physical Properties

• Glass Transition Temperature (Tg)

Physical Properties

• Decomposition Temperature (Td)

Physical Properties

• Effects of Multiple Lead-Free Cycles

Anti-CAF?

Lead-Free Failures

Electrical Properties

• Dielectric Constant (Dk)

Electrical Properties

• Dissipation Factor (Df)

Why Do We Care?

• Lead-Free Assembly

• Higher Layer Counts

• Smaller Feature Sizes

• Faster Edge Rates

How Do They Stack-Up?

PCB Categories

• Lead Assembly

• 2L Lead-Free Assembly

• ≥4L Lead-Free Assembly

• ≥4L Lead-Free Assembly (High Speed)

• RF (>2GHz)

Lead Assembly

• Traditional Epoxy System (/21)

• I.e. Nan Ya NP-140

• I.e. TLM TLM-140

• Meets Customer Tg≥135˚C Requirement

• Low Cost Materials (~0.8x)

• Easy to Manufacture

2L Lead-Free Assembly

• Modified Epoxy System (/101 /121)

• I.e. Nan Ya NP-140M - NOT NP-140!

• I.e. TLM TLM-140(mt)

• Pb-Free Compatible Materials

• Low Risk for Z-Axis CTE Failures

• Low-Medium Cost Materials (~0.9x)

• Easy to Manufacture

≥4L Lead-Free Assembly

• Modified & Filled Epoxy System (/99 /126)

• I.e. Nan Ya NP-175F - NOT NP-170!

• I.e. TLM TLM-170(t)

• Pb-Free Compatible Materials

• Anti-CAF

• Low CTE Z-Axis Expansion

• Medium Cost Materials (~1.0x)

• Difficult to Manufacture

• Routed NOT Punched!

High Speed & RF

• Modified & Filled Epoxy Systems (/29 /129)

• I.e. Isola FR408HR

• I.e. Nelco N4000-SI

• I.e. Panasonic Megtron4

• Same as ≥4L Lead-Free Assembly, But Lower Dk/Df c/o Specialty Fillers

• Higher Cost Materials (~1.8x)

• Difficult to Manufacture

• Other Important Considerations

Discussion

• HATS Testing

• Define Qualified Materials in PCB Specification

• Specify as IPC-4101 Slash Sheet

• More Engineering Consideration

• USA vs. Asia Materials

• Vendor Portability

• Customer Communication

• Cost vs. Quality