Skip to content

PCB Materials Reference Table

Vendor data for 13 laminates (Isola, Nelco, Panasonic, Rogers, Ventec, EMC), transcribed from datasheets. This is a staging table for data the app does not hold yet — not a second opinion on data it does.

Where these numbers stand relative to the app

The catalog wins, always. frontend/src/assets/pcbMaterials.json is the source of truth for Dk, Df, cost index, thickness and moisture; frontend/src/utils/thermal/thermalConstants.ts is the source of truth for Tg, thermal conductivity, CTE and Td. If a figure here disagrees with either, THEY are right and this page is stale. Prefer a value returned by the solver or the materials API over anything quoted here.

⛔ DK @10GHz here is the PROCESS Dk. The catalog holds the DESIGN Dk. They are different quantities and the gap is not drift. RO4350B is 3.48 in this table (IPC-TM-650 2.5.5.5 clamped stripline, the number the laminate measures) and 3.66 in the catalog (differential phase length, the number you design a 50 Ω line to). Correcting either one to match the other would be the error.

⚠ Names here are the vendor's spelling, not the app's — RO4350 B, EM-528, Megtron6 R-5775, N7000-2 HT, I-Tera MT40, Astra MT77, Tachyon-100G, VT-47. The canonical names are the catalog's keys (RO4350B, EM528, MEGTRON6, N7000-2HT, ITeraMT40, AstraMT77, Tachyon100G, VT47), which frontend/src/types/__tests__/materialNames.parity.test.ts pins across the three places they are written out. The Canonical column below is the join key; use it when cross-checking, never the display name.

What this page is FOR. It is the staging area for the catalog's unfinished widening. Measured 2026-09-14, the columns it carries for all 13 of its materials are filled for at most 3 of the catalog's 20: electricalStrengthVPerMil 3/20 (RO2929, VT47, EM827), materialFamily 3/20 (VT47, EM528, EM827), cafResistant 2/20 (VT47, EM827). Obsolete has no home anywhere else in the repo — it exists only here. IPC is partly covered by ipc_4101._SLASH_SHEETS, but as six family labels, not the per-material designations listed here.

⚠ The catalog's three filled materialFamily rows and two cafResistant rows AGREE with this table, which is consistent with it having been the source — but that is not proof of provenance, and electricalStrengthVPerMil does NOT line up (this table records no value for VT47 or EM827, where the catalog has 1300 and 1016). Treat a column moved from here into pcbMaterials.json as needing its own datasheet check, not a copy.

⛔ MEASURED 2026-09-14 — the CAF Resistant column does NOT match the datasheets, in both directions. Every local sheet in data/datasheets/susbtrates/ was searched for "CAF" / "conductive anodic filament". This table says Astra MT77 = Yes and I-Speed = Yes, but astra_mt77.pdf and i-speed.pdf contain no CAF mention at all (text extraction verified healthy — 4,416 and 5,382 characters, so the absence is real, not a parsing failure). Going the other way, its No rows for MEGTRON6, N7000-2HT and RO3003 line up with datasheets that are simply SILENT on CAF — which means this column's "No" encodes no published claim, not the vendor states it fails. Those are different facts and only the second would justify warning a user.

That is why cafResistant in the catalog was filled from the DATASHEETS, not from here: 10 of 20 laminates now carry true with a quoted citation, and the other 10 are ABSENT rather than false. Treat this column as a lead to check, never as a value to copy.

So: finishing the widening means promoting columns from here into the catalog. Retiring this page before that happens discards the only local copy of that data for the other ten materials, and the Obsolete flag entirely.

Last reconciled 2026-09-14.

Main table (key properties)

Name Canonical Manufacturer Application DK @10GHz DF @10GHz Tg (°C) Thermal Cond (W/m·K) Elec Strength (V/mil) Moisture Abs Td (°C) CTE X CTE Y CTE Z CAF Resistant Material Family IPC Rohs Obsolete
FR370HR FR370HR Isola Normal speed, Normal Loss 3.92 0.025 180 0.4 1350 0.15 340 13 14 45 Yes FR4 IPC-4101 /98 /99 /101 /126 Yes false
FR408HR FR408HR Isola High Speed, Low Loss 3.65 0.0095 190 0.4 1741 0.061 360 16 16 55 Yes FR4 IPC-4101 /98 /99 /101 /126 Yes false
I-Speed ISpeed Isola High Speed, Low Loss 3.63 0.0071 180 0.4 1741 0.061 360 16 16 60 Yes FR4 IPC-4101 /98 /99 /101 /126 Yes false
I-Tera MT40 ITeraMT40 Isola Very High Speed, Very low loss 3.45 0.0031 200 0.61 1133 0.01 360 12 12 55 Yes Hydrocarbon-PPE IPC-4103 /17 Yes false
Tachyon-100G Tachyon100G Isola Very High Speed/Frequency, Very Low Loss 3.02 0.0021 200 0.42 1500 0.1 360 15 15 45 Yes Hydrocarbon-PPE IPC-4103 /17 Yes false
Astra MT77 AstraMT77 Isola Very High Speed/Frequency, Very Low Loss 3 0.0017 200 0.45 1133 0.01 360 12 12 50 Yes Hydrocarbon-PPE IPC-4103 /17 Yes false
N7000-2 HT N7000-2HT Nelco Normal speed, Normal Loss 3.5 0.015 250 0.45 1200 0.35 376 9 12 45 NO Polyimide IPC-4101 /40 /41 /42 Yes false
Megtron6 R-5775 MEGTRON6 Panasonic High Speed, Low Loss 3.35 0.004 185 0.42 780 0.14 410 15 15 25 NO Hydrocarbon-PPE IPC-4101 /91 /102 Yes false
RO3003 RO3003 Rogers Very High Speed/Frequency, Very Low Loss 3 0.001 —¹ 0.5 — 0.04 500 17 16 32 NO Teflon-Ceramic IPC-4103 /11 Yes false
RO4350 B RO4350B Rogers Very High Speed/Frequency, Very Low Loss 3.48 0.0037 170 0.69 1300 0.06 390 10 12 45 YES Hydrocarbon-Ceramic IPC-4101 Yes false
VT-47 VT47 Ventec Normal speed, Normal Loss 4.27 0.016 250 0.5 — 0.12 340 12 12 45 YES FR4 IPC-4101E /97 /98 /99 /101 /126 Yes false
EM-528 EM528 EMC High speed, Low Loss 3.9 0.0061 185 — — 0.11 420 9 10 25 No FR4 /98 /99 /101 /126 Yes false
EM-827(I) EM827 EMC Normal speed, Normal Loss 4.3 0.019 — — — 0.15 350 12 15 40 YES FR4 /98 /99 /101 /126 Yes false

— = value not provided in source.

RO3003: PTFE (Teflon) composite — no traditional Tg; Rogers datasheet lists >350°C or N/A. App uses 260°C as conservative operational limit for thermal checks.

Electrical & frequency (1 MHz / 1 GHz)

Name Dk @1 MHz Dk @1 GHz Df @1 MHz Df @1 GHz
FR370HR 4.24 4.17 0.015 0.0161
FR408HR 3.72 3.69 0.0072 0.0091
I-Speed 3.65 3.65 0.0058 0.0058
I-Tera MT40 3.45 3.45 0.0031 0.0031
Tachyon-100G 3.04 3.04 0.0021 0.0021
Astra MT77 3 3 0.0017 0.0017
N7000-2 HT 3.8 3.5 0.015 0.015
Megtron6 R-5775 3.4 3.4 0.002 0.002
RO3003 3 3 0.001 0.001
RO4350 B 3.48 3.48 0.0031 0.0031
VT-47 4.27 4.27 0.016 0.016
EM-528 4 4 0.0047 0.0047
EM-827(I) 4.8 4.3 0.018 0.019

Mechanical & reliability

Name Tensile Modulus (Mpsi) Tensile Strength (Kpsi) Flexural Strength (Kpsi) CTI Class CTI Voltage Flammability UL 94 T260 (min) T288 (min)
FR370HR 3.178 35.62 77 3 175–249 V0 60 30
FR408HR 3.315 38.7 58 2 250–399 V0 60 30
I-Speed 2.73 35.6 62 2 250–399 V0 60 60
I-Tera MT40 2.784 35 58 3 175–249 V0 60 60
Tachyon-100G 2.417 25 41 3 175–249 V0 60 60
Astra MT77 2.366 24 39 3 175–249 V0 60 60
N7000-2 HT 3.3 18.9 37 4 100–174 V0 12 120
Megtron6 R-5775 2.31 — 61 0 >600 V0 120 15
RO3003 0.119 — 3335.87* 0 >600 V0 30 60
RO4350 B 2.053 — 65.27 — — V0 — 25
VT-47 — — — — — V0 — —
EM-528 — — — — — V-0 — —
EM-827(I) — — — — — V-0 — —

RO3003 flexural value 3335.87 may be a typo (e.g. 33.6 Kpsi); confirm with datasheet.

Descriptions & designations

Name Description Procim base material code
FR370HR Multifunctional epoxy / Woven E-Glass 90
FR408HR Multifunctional epoxy / Woven E-Glass 113
I-Speed Multifunctional epoxy / Woven E-Glass 144
I-Tera MT40 Hydrocarbon-PPE / Woven E-Glass 191
Tachyon-100G Hydrocarbon-PPE / Woven E-Glass 195
Astra MT77 Hydrocarbon-PPE / Woven E-Glass 200
N7000-2 HT Polyimide / Woven E-Glass 61
Megtron6 R-5775 Hydrocarbon-PPE / Woven E-Glass 114
RO3003 Ceramic filled PTFE / Woven E-Glass 71
RO4350 B Hydrocarbon-Ceramic / Woven E-Glass 6
VT-47 Multifunctional epoxy / Woven E-Glass 94
EM-528 Multifunctional epoxy / Woven E-Glass —
EM-827(I) Multifunctional epoxy / Woven E-Glass —
  • HDI Preferred: Yes for all 13 materials.
  • Offered by Sierra (Material availability TBD): Yes for all.
  • Halogen free: Yes (where specified).
  • Blank cells in source data are shown as — or omitted.