MedPCB manufactures SF305 flexible and rigid-flex bare boards designed for critical medical device projects.
• Genuine Shengyi SF305 Halogen-Free Polyimide FCCL
• UL 94 V-0 Flame Resistance
• Flexible PCB up to 8 Layers & Rigid-Flex PCB up to 20 Layers
• ISO 13485 & IPC Class 2/3 Manufacturing
An SF305 PCB is a flexible printed circuit built on Shengyi SF305, a halogen-free flexible copper-clad laminate (FCCL) that bonds copper foil to polyimide film. The SF305 laminate is rated UL 94 V-0, is RoHS compliant, and is paired with Shengyi SF305C coverlay, the insulating film applied over the finished polyimide flexible circuit.
SF305 carries a UL 94 V-0 rating and meets EU RoHS requirements. Its documented electrical and mechanical characteristics include a dielectric constant of 3.6 at 10 GHz, a dissipation factor of 0.028, and over 600 folding cycles under defined MIT test conditions.
MedPCB manufactures custom flex and rigid-flex PCBs using genuine Shengyi SF305 for medical electronics. We implement full material traceability and production controls aligned with your project requirements.
MedPCB manufactures SF305 flex and rigid-flex PCBs within an ISO 13485 and ISO 9001 certified quality management system. Production records, process controls, and material traceability support the documentation requirements of medical device manufacturing. We manufacture and inspect finished boards to meet applicable IPC-6013 Class 2 or Class 3 requirements.
MedPCB provides a complimentary DFM review to identify manufacturing risks before tooling release. Our engineers review the flex stackup, coverlay openings and pullback, bend zones, annular rings, copper weight, and etch compensation against your fabrication data. Any manufacturability concerns are raised for your review before production begins.
MedPCB sources genuine Shengyi SF305 laminates directly from Shengyi Technology according to your specified construction. To ensure complete lot traceability, we maintain certificates of conformance, lot numbers, and current technical datasheets for every production run.
MedPCB supports both SF305 flex and rigid-flex PCB manufacturing, allowing your project to use one qualified manufacturing partner across different circuit constructions. We manufacture up to 8-layer flex PCBs and up to 20-layer rigid-flex PCBs using SF305 flex materials with qualified rigid cores and prepreg.
MedPCB maintains full material traceability from incoming laminate rolls to final packaging, tracking every SF305 order to its specific production lot. Our rigorous quality control includes automated optical inspection, flying probe testing, IPC microsectioning, and impedance validation, accompanied by complete UL and REACH compliance documentation.
| Capability | Flex PCB | Rigid-Flex PCB |
|---|---|---|
| Material | Shengyi SF305 FCCL; Shengyi SF305C Coverlay | Shengyi SF305 flex layers with qualified rigid PCB cores and prepreg |
| Layer Count | Up to 8 layers | Up to 20 layers |
| Board Thickness | 0.5–0.8 mm (without stiffener) | 0.3–4.0 mm |
| Board Size | Min: 4 × 8 mm (without bridge) Max: 9 × 23 in (for PI ≥ 1 mil) |
Min: 10 × 15 mm Max: 406.4 × 736.6 mm |
| Min. Bend Radius | Single Layer: 3–6× board thickness Double Layer: 6–10× board thickness Multi-Layer: 10–15× board thickness Dynamic Bend: 20–40× board thickness |
Follows Flex PCB parameters |
| Surface Treatment | HASL, ENIG, ENEPIG, Electrolytic Nickel Gold, Soft Gold, Hard Gold, Immersion Silver, Immersion Tin, OSP | |
| Stiffeners & Adhesives | Supports PI / FR4 stiffeners and qualified 3M-series bonding adhesives | |
Unsupported polyimide absorbs moisture and relaxes after copper is etched away, which moves features away from the tooling datum. The result is annular ring breakout and coverlay misregistration, usually found at final inspection after plating and finishing.
Our Solution: MedPCB bakes incoming SF305 before imaging, supports thin cores on pinned frames during wet processing, and scales artwork for copper weight and film thickness. Panels are measured against reference targets after etching, and that measured movement sets the scaling factor for the next lot.
Coverlay adhesive must fill the space beside each conductor without reaching the pad area, and the film stretches while it is placed. Adhesive on a pad causes solderability rejects, and insufficient flow leaves voids that retain process chemistry and cause corrosion.
Our Solution: SF305C openings are cut and inspected before lay-up, placement is aligned optically to fiducial marks, and lamination uses a stepped vacuum cycle matched to the coverlay adhesive. Absence of voids beside conductors is confirmed by microsection, and pad cleanliness by automated optical inspection.
Repeated bending places mechanical stress on copper conductors and can lead to cracking when the bend radius, copper type, or stack-up is not properly selected. Dynamic applications therefore require careful control of copper type, conductor placement, bend radius, and bend-zone construction.
Our Solution: MedPCB utilizes rolled annealed copper for dynamic medical applications, ensuring conductors are optimally placed near the neutral bending axis. We manufacture these boards by keeping plated holes and stiffener edges outside the bend zone, verifying folding endurance through IPC-TM-650 MIT folding tests.
The dielectric in a flex circuit is a thin film, so a small change in line width or coverlay thickness shifts impedance far more than on a rigid core. Impedance outside tolerance causes signal reflections and reduced margin, and it is usually found during device integration, too late for a rebuild.
Our Solution: MedPCB calculates line geometry from the laminate values for the lot in production, controls trace width by controlled etching and measured first-article line width, and tests coupons by time domain reflectometry against the tolerances listed in the capability table. The coupon report is supplied with the lot.
MedPCB manufactures SF305 circuits using halogen-free polyimide laminates that meet strict requirements for flame resistance, repeated folding, and stable insulation. The following table summarizes selected electrical, mechanical, dimensional, and thermal properties of Shengyi SF305 under the published test conditions.
| Property | Test Condition | Typical Value |
|---|---|---|
| Dielectric Constant (10GHz) | SPDR (C-24/23/50) | 3.6 |
| Dissipation Factor (10GHz) | SPDR (C-24/23/50) | 0.028 |
| Volume Resistivity | C-96/35/90 | 1.5 × 10^8 MΩ-cm |
| Dimensional Stability | After Etched | -0.0684 / 0.0691 % |
| Folding Endurance | R0.8 × 4.9N | > 600 times |
| Solder Resistance | 288°C, 10s | No delamination |
| Flammability | E-24/125 | V-0 |
Need an SF305 flex PCB for your medical device? Send your Gerber files for a Free DFM Review and Quote.
This customer builds disposable ECG patches, and the circuit had to be formed to a curved adhesive housing without a connector. We produced a double-sided SF305 flex circuit with rolled annealed copper, SF305C coverlay set back from the formed bend, and ENIG finish on the electrode pads. Panels were inspected optically after etching and after lamination, then electrically tested against the supplied net list to IPC-6013 Class 2.
When presented with a strict 4 × 8 mm board outline limited by a pre-tooled housing, MedPCB manufactured the fine outer layer geometry on 18 µm copper and applied an ENEPIG surface finish for contact reliability. To protect the small polyimide circuit and maintain the required outline accuracy, we laser-profiled the board. The production lot was released only after passing Class 3 dimensional verification and continuity testing.
This customer's product required an interconnect that bends continuously through an articulating joint. We handled it with rolled annealed copper, a symmetric stackup that keeps conductors close to the neutral bending axis, no plated-through holes inside the bend zone, and a bend radius at the upper end of the published dynamic range. Microsection of the hole wall and coverlay adhesion completed release, together with continuity and isolation testing.
For this diagnostics customer, the governing requirement was stable leakage performance on a sensor tail worn against skin. We ran SF305 with soft gold on the sensor contacts, coverlay extended to the edge of the tail, and mechanical drilling at 0.10 mm. Checks completed before shipment: insulation resistance measurement, automated optical inspection, and microsection to IPC-A-600 Class 3.
Our Medical SF305 Flex PCB FAQ addresses key questions regarding Shengyi SF305 flexible laminate properties and fabrication standards. We cover flexible characteristics, UL 94 V-0 halogen-free flame resistance, insulation resistance, multilayer construction, lead-free reflow compatibility, surface finishes, and DFM support. For every medical SF305 flex PCB project, we guarantee high-precision manufacturing engineered for critical healthcare applications.
1 to 8 Layers
Static 3-6x (1L) | Dynamic 20-40x
Polyimide (PI), FR4, 3M Tape
Up to 20 Rigid Layers, Up to 18 Flex Layers
Ultra-Long & Ultra-Thin HDI Rigid-Flex
Flex-to-Install & Dynamic Flex options
High-Precision SMT, Low-Temperature Reflow, Selective Soldering
Micro-SMD, Fine-Pitch BGAs, Connectors, QFNs, Sensors
Single-Sided Flex, Double-Sided Flex, Multi-Layer Flex
Panasonic MEGTRON 6 R-5775/R-5670
Ultra-Low Transmission Loss & High Heat Resistance
ISO 13485, IPC Class 2 and Class 3
1–4 layers
Min ½ OZ, Max 4 OZ standard; Min ⅓ OZ, Max 100 OZ advanced
Aluminum, FR4, copper, ceramic, polyimide, polyester, glass, and hybrid laminates
High Thermal Stability & Low Moisture Absorption
Dk 3.5 & Low Df for Low-Loss Signal Transmission
ISO 13485, IPC Class 2 and Class 3
Isola 370HR HDI Technology and Lead-Free Assembly
180°C Tg and 340°C Td
ISO 13485, IPC Class 2 and Class 3
4–40 layers
Standard: 500 × 600 mm (19" × 23") Advanced: 1100 × 500 mm (43" × 19")
High-Tg FR4, Rogers, Polyimide, Megtron, Taconic, Arlon
4–40 layers
Supports 1+N+1, 2+N+2, and Any-Layer HDI
Microvias, Fine Lines, and Sequential Lamination
01005 (0.4mm*0.2mm)
Support SMT & Thru-hole
Turnkey, Partial turnkey, Consigned
English
French
German
Japanese
Korean
