High processing temperatures are an essential consideration when selecting a PCB laminate. Elevated temperatures cause delamination, which results from the weakening of the material’s copper/dielectric bond.
PCB materials used for a lead-free circuit assembly need to endure high re-flow oven and rework temperatures. So, these materials’ thermal performance and reliability are necessary to result in a properly assembled PCB.
High re-flow oven temperatures can diminish the strength of the copper/dielectric bond in standard PCB laminates, which affects the reliability of the PCB. Lead-free laminates are engineered to maintain their electrical and mechanical stability at raised processing temperatures.
When your design calls for a lead-free PCB, a careful comparison of the electrical and mechanical characteristics of PCB materials can help you select the right base material for your PCB.
This table provides you with quick access to important information you need for your design.
| Product | ITEQ ITEQ180A |
Isola 370HR |
Isola 185HR |
Isola IS415 |
Ventec VT47 |
| Material Type | High Tg Epoxy | High Tg Epoxy | High Tg Epoxy | High Tg Epoxy | High Tg Epoxy |
| Halogen Free | No | No | No | No | No |
| Flammability UL94 | V-0 | V-0 | V-0 | V-0 | V-0 |
| Glass Transition Temp Tg – ºC | 175 | 180 | 180 | 200 | 180 |
| Td (Decomposition Temp) by TGA – ºC | 345 | 340 | 340 | 370 | 355 |
| Dk 1 GHz | 4.17 | 4.04 | 3.71 | 4.3 | |
| Dk 2-3 GHz | 4.30 | 4.04 | 4.01 | 3.72 | |
| Dk 10-12 GHz | 4.10 | 3.92 | 3.88 | 3.71 | |
| Df 1 GHz | 0.0150 | 0.0192 | 0.0131 | 0.016 | |
| Df 2-3 GHz | 0.015 | 0.021 | 0.0200 | 0.0120 | |
| Df 10-12 GHz | 0.016 | 0.025 | 0.0236 | 0.0125 | |
| Moisture Absorption (%) | 0.10% | 0.15% | 0.15% | 0.15% | 0.12% |
| CTE X-Axis (PPM/ºC) Pre Tg | 11 to 13 | 13 | 13 | 13 | 11 |
| CTE Y-Axis (PPM/ºC) Pre Tg | 13 to 15 | 14 | 14 | 13 | 13 |
| CTE Z-Axis (ppm/ºC) Pre Tg | 45 | 45 | 40 | 45 | 45 |
| Peel Strength – 1oz (35μm) – N/mm | 1.40 | 1.25 | 1.04 | 1.225 | 1.3 |
| T260 – minutes | 60 | 60 | 60 | >60 | |
| T288 – minutes | 20 | 30 | >15 | >20 | >30 |
| Flexural strength – N/mm2 | X – 500 to 530 Y- 410 to 440 |
X – 620.53 Y – 530.90 |
X – 669.48 Y – 372.32 |
X – 511.59 Y – 355.77 |
X – 500 Y – 420 |
| Young’s modulus – N/mm2 | X – 25,814 Y – 21,912 |
X – 25,993 Y – 23008 |
X – 24,338 Y – 22063 |
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| Tensile strength – N/mm2 | X – 385 Y – 245 |
X – 368 Y – 246 |
X – 302 Y – 218 |
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| Volume Resistivity – MΩ/cm A. After moisture resistance B. At elevated temperature |
1×109 | a) 3.0 x 108 b) 7.0 x 108 |
a) 3.0 x 108 b) 7.0 x 108 |
a) 3.81 x 108 b) 3.90 x 108 |
a) 5x 108 |
| Dielectric strength – kV | >50 | >50 | >50 | 60 | |
| Surface Resistivity – MΩ A. After moisture resistance B. At elevated temperature |
1×108 | a) 3.0 x 106 b) 2.0 x 108 |
a) 3.0 x 106 b) 2.0 x 108 |
a) 2.81 x 106 b) 2.64 x 108 |
a) 5 x 107 |
| Dimensional stability – mm/M | |||||
| Thermal Conductivity – W/mK | 0.40 | 0.40 | 0.40 | 0.50 | |
| % Z-axis Expansion (50-260ºC) (CTE Z Axis) | 2.70% | 2.8% | 2.7% | 2.8% | 2.3% |