SF305C PCB Fabrication & Assembly

SF305C is a flexible-circuit material reference used in customer documentation. Highleap Electronics is a PCB fabrication and PCB assembly factory. We do not manufacture base laminate materials.

We review the approved design, the nominated construction, and production constraints so that the finished board can be built and assembled to the project requirements.

Manufacturing with customer-nominated SF305C material

Highleap supports flex and rigid-flex projects that require compact routing and assembly coordination. The useful starting point is a complete fabrication package, rather than a generic material claim: stackup drawing, layer data, drill chart, impedance requirements, and the intended assembly process.

For this type of program, our engineering attention is directed to dynamic-area protection, transition design, and reliable termination support. The final construction is reviewed against the actual board design, availability, and the customer-approved document set.

Project review inputs

Before fabrication release, our CAM team reviews rigid-flex interface, bend requirements, copper pattern, adhesive system, and exposed-pad needs. Clear input at this stage helps avoid last-minute construction changes and gives purchasing, fabrication, and assembly teams the same project baseline.

Where a material callout is critical, please identify the exact construction and approved source documentation in the order package. We can then confirm manufacturability and propose practical board-level alternatives if the nominated construction is unavailable.

Material Overview

Manufacturer: Shengyi Technology Co., Ltd.
Product Model: SF305C
Product Category: Flexible Circuit Coverlay
Base Material: Polyimide (PI) Film
Flammability Rating: UL94 V-0
Compliance: Halogen-Free & EU RoHS

Characteristics

Halogen free, flammability UL94 V-0
High bonding strength, good dimensional stability and thermal resistance
Low adhesive flowing, good processability, suitable for both fast and traditional lamination style
Compatible with EU RoHS directive, free of Pb, Hg, Cd, Cr⁶⁺, PBB, PBDE, etc.

Applications

FPC Coverlay
Power Battery Protection Board
CCM (Camera Module)
Battery & Antenna Modules
FPM & LCD Modules
Light-Bar Module
TP (Touch Panel) Module

Engineering planning checklist

Review area	Project input	Manufacturing focus
Construction	Approved stackup and finished thickness	Layer registration and build planning
Copper and routing	Weights, controlled nets, and plane requirements	Etch compensation and signal reference continuity
Holes and features	Drill chart, via type, and tolerances	Drill, plating, and inspection sequence
Assembly	Component, finish, and process constraints	Profile planning and fit verification
Acceptance	Test and documentation requirements	Inspection records for the agreed build

This checklist is fabrication guidance, not a substitute for the material owner’s current technical documentation.

Test Item		Treatment Condition	Unit	Property Data
				IPC Standard	Typical Value
				IPC Standard	SF305C 0515	SF305C 1025
Resin Flow		-	mm	-	＜0.15	＜0.15
Peel Strength (90°)*		A	N/mm	≥0.7	0.9	1.1
Peel Strength (90°)*		288℃, 5s	N/mm	≥0.5	0.9	1.0
Thermal Stress*		300℃, 10s	-	288℃, 10s No Delamination	No Delamination	No Delamination
Dimensional Stability	MD	E-0.5/150	%	±0.2	±0.1	±0.1
Dimensional Stability	TD	E-0.5/150	%	±0.2	±0.1	±0.1
Chemical Resistance		After Chemical Exposure	%	≥80	＞90	＞90
Volume Resistivity		C-96/35/90	MΩ·cm	≥10⁶	5.5×10⁷	6.0×10⁷
Surface Resistance		C-96/35/90	MΩ	≥10⁴	3.0×10⁶	3.5×10⁶

Third-party material and reference-data notice

SF305C is a flexible-circuit material reference used in customer documentation. It is not a Highleap product. Highleap does not make PCB base materials and is not presented as the brand owner, an authorized representative, distributor, affiliate, or endorser for the named material.

Any material-related discussion, values, or process notes on this page are non-binding reference guidance, not guaranteed specifications. For critical performance, tolerances, approved constructions, availability, or compliance requirements, use the current documentation from the material manufacturer or trademark owner and confirm it before production release.

Fabrication planning and process control

For SF305C builds, the manufacturing plan is based on layer-build review, coverlay preparation, stiffener planning, and assembly fixture feedback. Our role is to turn the customer-approved board package into controlled fabrication instructions, with attention to traceability, tooling, and in-process checks.

Design-for-manufacturing review before release
Stackup and copper construction confirmation
Drill, plating, and routing process planning
Defined inspection points matched to the order requirements

Material selection remains with the customer and the applicable material provider; Highleap focuses on the buildable PCB and PCB assembly process.

Specifications	PI Film Thickness (um)	Adhesive Thickness (um)
SF305C 0515	12.5	15
SF305C 0520	12.5	20
SF305C 0525	12.5	25
SF305C 1025	25	25
SF305C 1030	25	30

Assembly and verification

When assembly is included, we align the board construction with component data, package clearances, moisture handling, soldering profile, and the agreed test approach. For this project type, verification can include continuity and isolation test, visual inspection, dimensional measurement, and bend-area review.

Send the Gerber or ODB++ data, fabrication drawing, bill of materials, pick-and-place data, and any controlled-impedance or reliability requirements for a focused engineering review. Our team will return practical PCB fabrication and PCBA feedback for the requested build.

Contact Highleap Electronics to request a quotation or DFM review.

Documentation control for SF305C projects

Each board is reviewed as its own manufacturing package. We compare the customer drawings, data files, stackup, drilling details, assembly inputs, and acceptance notes before release. This keeps dynamic-area protection, transition design, and reliable termination support connected to a practical fabrication plan rather than relying on generic published material statements.