Multilayer
Layer material
| Standard | With overhead expenses | |
Material type | FR4 (Tg 135 °C) | FR4 (Tg 150°C), FR4 (Tg 170 °C) |
Thickness without the basic copper | 0.20mm; 0.25mm; 0.36mm; 0.51mm; 0.76mm; 1.00mm | 0.30mm; 0.41mm; 0.61mm |
Basic copper | 18µm; 35µm | 70µm; 105µm |
Thickness tolerance including basic copper | MIL-S-139 4 9H tolerance, last edition, grade II IPC 4101A grade B | |
Material characteristics | Permittivity er at 1MHz | 4.6 - 4.9
|
Prepreg
| Standard | With overhead expenses | |
Material type | FR4 (Tg 135 °C) | FR4 (Tg 150°C), FR4 (Tg 170 °C) |
Prepreg type | 1080; 2116; 7628 | |
Material thickness | 63µm; 110µm; 180µm | |
Material characteristics | Permittivity er at 1MHz | 4.6 - 4.9
|
Min. final copper depending on basic copper and PCB thickness
| Standart | ||
Final copper /
| 43µm / 18µm / 0.8 ÷ 2.0mm | 95µm / 70µm / 0.8 ÷ 2.0mm
|
Tolerance | ±10% | ±10% |
Multilayers are constructed of FR4 base material, internal and prepreg layers. The package is laminated with copper foil. The entire minimum prepreg thickness between each two layers starting from the core should at least double the thickness of the basic copper of the material. A symmetrical structure of the multilayer is preferable to prevent material deformations. A multilayer can also be produced asymmetrically, in case of customer’s request.
We have the following FR4 prepregs in stock:
| Type | Typical thickness |
| 1080 | approx. 0,063 mm |
| 2116 | approx. 0,110 mm |
| 7628 | approx. 0,180 mm |
Standard structure of SET multilayers
The final thickness of the multilayer is the thickness of the packet after pressing, including the thickness of the galvanic coats and the protective mask.
