ITEQ high-Tg FR-4
ITEQ IT-180A PCB: High-Tg, Low-CTE Lead-Free FR-4
ITEQ IT-180A is a lead-free compatible, high-Tg, low-CTE filled epoxy FR-4: Tg 180 °C (DSC), Td 350 °C and 2.7% z-axis expansion from 50 to 260 °C. It is one of our two default high-Tg FR-4 materials, alongside Shengyi S1000-2M.
- Tg (DSC)
- 180 °C
- Td
- 350 °C
- Dk @ 1 GHz
- 4.4
- Z-expansion 50–260 °C
- 2.7%
What is IT-180A
What is ITEQ IT-180A?
ITEQ IT-180A is a lead-free compatible, high-Tg, low-CTE, multifunctional filled epoxy FR-4 laminate. It has a Tg of 180 °C by DSC, a Td of 350 °C and only 2.7% z-axis expansion between 50 and 260 °C, which protects plated holes through repeated lead-free reflow.
IT-180A meets or exceeds IPC-4101C /21, /24, /26, /98, /99, /101, /121, /124, /126 and /129, so it fits a wide range of high-Tg FR-4 callouts. ITEQ is our second default FR-4 supplier after Shengyi, and IT-180A is the grade we use most for multilayer and HDI boards.
Properties
ITEQ IT-180A typical properties.
| Property | Typical value |
|---|---|
| Tg (DSC) | 180 °C |
| Td | 350 °C |
| CTE X/Y (40–125 °C) | 10–13 ppm/°C |
| CTE Z α1 / α2 | 45 / 210 ppm/°C |
| Z-axis expansion, 50–260 °C | 2.7% |
| T260 / T288 | > 60 / > 30 min |
| Thermal stress 10 s @ 288 °C | Pass (unetched and etched) |
| Dk @ 1 MHz / 1 GHz / 2 GHz / 10 GHz | 4.4 / 4.4 / 4.3 / 4.1 |
| Df @ 1 MHz / 1 GHz / 2 GHz / 10 GHz | 0.014 / 0.015 / 0.015 / 0.016 |
| Electric strength (min.) | 45 kV/mm |
| Moisture absorption (max.) | 0.12% |
| Flammability | UL 94 V-0 |
| Max. operating temperature (MOT) | 130 °C |
When to use
When to specify an ITEQ PCB on IT-180A.
An ITEQ PCB on IT-180A fits where a board needs more thermal margin than standard FR-4: lead-free assembly with two or more reflows, eight or more layers, HDI with sequential lamination, or automotive and industrial thermal cycling. Its filled, low-CTE resin keeps z-axis expansion down, which is what protects via barrels.
IT-180A is a standard-loss FR-4 (Df about 0.015 at 1 GHz). For 10 Gbps+ channels choose a low-loss material such as ITEQ IT-968, Isola FR408HR or Megtron.
IT-180A vs others
IT-180A vs Shengyi S1000-2M vs Isola 370HR.
| Laminate | Tg | Td | Z-expansion 50–260 °C | Dk @ 1 GHz |
|---|---|---|---|---|
| ITEQ IT-180A | 180 °C (DSC) | 350 °C | 2.7% | 4.4 |
| Shengyi S1000-2M | ≈ 185 °C | ≈ 355 °C | — | ≈ 4.6 |
| Isola 370HR | 180 °C (DSC) | 340 °C | ≈ 2.7% | ≈ 4.04 |
All three are high-Tg, CAF-resistant FR-4 laminates that process on standard lines. IT-180A and S1000-2M are often offered as equivalents to 370HR callouts; we substitute only with your written approval.
Stack-up
Stack-up guidance on IT-180A.
IT-180A is available in the usual range of cores and prepregs (106, 1080, 2116, 7628 and others). Dk falls as resin content drops, so we model impedance with the Dk of each glass style. For fine-pitch differential pairs we use spread-glass styles to limit fiber-weave skew.
- Glass-style-specific Dk in impedance models
- Balanced copper and prepreg to control warpage
- Specify finished thickness and tolerance
- Allow “or equivalent” if lead time is critical
Other ITEQ grades
Other ITEQ laminates.
| Grade | Class | Typical use |
|---|---|---|
| IT-158 | Mid-Tg FR-4 | Lead-free with standard reliability |
| IT-180A | High-Tg, low CTE | Multilayer, HDI, automotive |
| IT-968 | Low loss | High-speed digital |
| IT-988G | Very low loss | Networking and servers |
Lead-free reflow
Lead-free reflow and reliability.
IT-180A passes 10-second thermal stress at 288 °C etched and unetched, with T260 above 60 minutes and T288 above 30 minutes. Low z-axis expansion keeps strain on plated holes down through two-sided reflow, wave or selective solder and rework. As with any epoxy laminate, boards should be kept dry and baked before assembly if exposure limits are exceeded.
RFQ
What to include in an IT-180A RFQ.
- Laminate name and grade exactly as on your drawing, or “or equivalent” if substitution is allowed
- “ITEQ IT-180A” or the IPC-4101 slash sheet if an equivalent is acceptable
- Number of reflow cycles and any automotive or Class 3 requirement
- Layer count, finished thickness and tolerance
- Impedance targets and reference layers
- IPC class, quantity and schedule
FAQ
Material questions.
What is the Tg of IT-180A?
180 °C by DSC, with a Td of 350 °C.
What is the dielectric constant of IT-180A?
4.4 at 1 GHz and 4.1 at 10 GHz, at the resin contents stated in the ITEQ data sheet.
Is IT-180A lead-free compatible?
Yes. It is a lead-free compatible, high-Tg, low-CTE FR-4.
IT-180A vs Isola 370HR?
Both are 180 °C Tg, CAF-resistant FR-4 laminates with similar z-axis expansion. IT-180A is often offered as an equivalent; we substitute only with your approval.
Which IPC-4101 slash sheets does IT-180A meet?
/21, /24, /26, /98, /99, /101, /121, /124, /126 and /129, per the ITEQ data sheet.
Is IT-180A good for high speed?
For digital up to a few Gbps on short channels. For faster links use a low-loss grade such as IT-968, FR408HR or Megtron.
Ready when your files are
Send your stack-up for a material check.
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