Flexible circuit boards

Flexible circuit board

Because of the advantages (for example, cost, space, and weight savings) that flexible and Rigid-Flex-circuit boards have for some projects, they are used ever more frequently. Multi-CB can produce your flexible circuit boards with the highest quality, either as prototype or as series with 1-10 layers.

The standard surface used is chemical gold (ENIG), the contours are formed according to requirements, preferably using laser cutting, or also with mechanical milling.

You should discuss the selected materials and design for the construction and layout of flexible circuit boards with us in the planning phase; we can assist you to work out the optimum solution!

Please contact our CAM-Station-Team (tel. +49-8104-6280) for additional technical questions about flexible circuit boards. Please mind also our Design-Aid for flexible circuit boards.
PCB-Calculator: Flexible PCBs

Technical options for flexible circuit boards

Options Notes
OptionsDesign 1 to 10 layers, plated-throughNotesLayer buildup
OptionsConductor width min. 100µm Notes 
OptionsAnnular ring min. 100µm Notes 
OptionsVia min. Ø 150µm Notes 
OptionsSurfaces Chemical gold (recommended), immersion tin, HAL lead-freeNotesSurfaces
OptionsMaterials Polyimide, high Tg polyimideNotesMaterials
OptionsMaterial thickness starting at 25µm foil plus copperNotes 
OptionsCopper thickness from 18µmNotes 
OptionsStiffener 0,025µm - 3,20mmNotes 
OptionsMax. size 250mm x 450mmNoteslarger on request
OptionsCover Coverlay or flexible solder-stopNotes 
OptionsCover bridge Coverlay: ≥ 200µmNotes 
Options  Flex. solder-stop: ≥ 100µmNotes 
OptionsImpedance control Yes (10% tolerance)Notes 
OptionsAdhesive tape 3M 9077NotesMaterials

Material for flexible circuit boards

Material for flexible PCBsPCB recommended operating temperatureMax. recommended operating temperatureFlexible circuit copper typeCopper typePCB Glass transition temperature TgGlass transition temperature TgPCB dielectric constantεrPCB CTE-zCTE-zPCB electric strenghtElectric strenghtPCB surface resistivitySurface resistivityPCB peel strengthPeel strength
Material for flexible PCBs PCB recommended operating temperatureMax. recommended operating temperature°CFlexible circuit copper typeCopper type*PCB Glass transition temperature TgGlass transition temperature Tg°CPCB dielectric constantεr@1MHzPCB CTE-zCTE-zppm/°CPCB electric strenghtElectric strenghtKV/mmPCB surface resistivitySurface resistivityPCB peel strengthPeel strengthN/mm
Material for flexible PCBsPolyimide + AdhesivePCB recommended operating temperatureMax. recommended operating temperature Flexible circuit copper typeCopper type PCB Glass transition temperature TgGlass transition temperature Tg PCB dielectric constantεr PCB CTE-zCTE-z PCB electric strenghtElectric strenght PCB surface resistivitySurface resistivity PCB peel strengthPeel strength 
Material for flexible PCBsShengyi SF305PCB recommended operating temperatureMax. recommended operating temperature105°Flexible circuit copper typeCopper typeRAPCB Glass transition temperature TgGlass transition temperature Tg-PCB dielectric constantεr3,6PCB CTE-zCTE-z-PCB electric strenghtElectric strenght21PCB surface resistivitySurface resistivity1 x 10^5PCB peel strengthPeel strength1,1
Material for flexible PCBsAdhesivelessPCB recommended operating temperatureMax. recommended operating temperature Flexible circuit copper typeCopper type PCB Glass transition temperature TgGlass transition temperature Tg PCB dielectric constantεr PCB CTE-zCTE-z PCB electric strenghtElectric strenght PCB surface resistivitySurface resistivity PCB peel strengthPeel strength 
Material for flexible PCBsDuPont Pyralux APPCB recommended operating temperatureMax. recommended operating temperature180°Flexible circuit copper typeCopper typeRAPCB Glass transition temperature TgGlass transition temperature Tg220PCB dielectric constantεr3,4PCB CTE-zCTE-z25PCB electric strenghtElectric strenght256PCB surface resistivitySurface resistivity1 x 10^10PCB peel strengthPeel strength1,8
Material for flexible PCBsPanasonic RF775PCB recommended operating temperatureMax. recommended operating temperature130°Flexible circuit copper typeCopper typeEDPCB Glass transition temperature TgGlass transition temperature Tg343PCB dielectric constantεr3,2PCB CTE-zCTE-z-PCB electric strenghtElectric strenght276PCB surface resistivitySurface resistivity1 x 10^8PCB peel strengthPeel strength1,7
Material for flexible PCBsThinflex W-05050PCB recommended operating temperatureMax. recommended operating temperature105°Flexible circuit copper typeCopper typeEDPCB Glass transition temperature TgGlass transition temperature Tg350PCB dielectric constantεr3,3PCB CTE-zCTE-z24PCB electric strenghtElectric strenght216PCB surface resistivitySurface resistivity1 x 10^5PCB peel strengthPeel strength0,6
Material for flexible PCBsPI CoverlayPCB recommended operating temperatureMax. recommended operating temperature Flexible circuit copper typeCopper type PCB Glass transition temperature TgGlass transition temperature Tg PCB dielectric constantεr PCB CTE-zCTE-z PCB electric strenghtElectric strenght PCB surface resistivitySurface resistivity PCB peel strengthPeel strength 
Material for flexible PCBsShengyi SF305CPCB recommended operating temperatureMax. recommended operating temperature105°Flexible circuit copper typeCopper type-PCB Glass transition temperature TgGlass transition temperature Tg-PCB dielectric constantεr-PCB CTE-zCTE-z-PCB electric strenghtElectric strenght-PCB surface resistivitySurface resistivity3 x 10^6PCB peel strengthPeel strength-
Material for flexible PCBsDuPont Pyralux FRPCB recommended operating temperatureMax. recommended operating temperature180°Flexible circuit copper typeCopper type-PCB Glass transition temperature TgGlass transition temperature Tg-PCB dielectric constantεr3,5PCB CTE-zCTE-z-PCB electric strenghtElectric strenght138PCB surface resistivitySurface resistivity1 x 10^7PCB peel strengthPeel strength-
Material for flexible PCBsAdhesive tapePCB recommended operating temperatureMax. recommended operating temperature Flexible circuit copper typeCopper type PCB Glass transition temperature TgGlass transition temperature Tg PCB dielectric constantεr PCB CTE-zCTE-z PCB electric strenghtElectric strenght PCB surface resistivitySurface resistivity PCB peel strengthPeel strength 
Material for flexible PCBs3M 9077PCB recommended operating temperatureMax. recommended operating temperature150°Flexible circuit copper typeCopper type-PCB Glass transition temperature TgGlass transition temperature Tg-PCB dielectric constantεr-PCB CTE-zCTE-z-PCB electric strenghtElectric strenght-PCB surface resistivitySurface resistivity-PCB peel strengthPeel strength-

* RA = Rolled copper, suitable for dynamic, flexible applications; ED = Electrolytically deposited copper , only suited for stable and semi-dynamic applications

UL certification for flexible circuit boards

At Multi-CB, you also get one-sided and multilayer flexible printed circuit boards with UL certification.

Flexible Circuit Board Microsection

2 Layer Flex-PCB (PTH) Microsection

Example - Stiffener

Flexible circuit board with ZIF connector 250µm

ZIF connector, picture by courtesy of Molex

You can order your flexible circuit boards with a stiffener. The available thicknesses are: 0,075mm - 3,20mm.

Popular are the thicknesses0,030mmand0,025mm, e.g. forZIF connectors.

Polyimid-Stiffener: 0,050mm - 0,225mm

FR4-Stiffener: 0,30mm - 3,20mm