Your Trusted Prototype PCB Manufacturing And Assembly Partner.
When you partner with us, we do everything to ensure your PCB manufacturing and assembly are completed on time to your specifications with the highest quality.
Lead-Free PCB Assembly Service
RoHS and REACH compliant PCB assembly using SAC305, SAC307, and SN100C lead-free solder alloys. Fully certified for global electronics markets.
oHS ✓ · REACH ✓ · IPC-A-610 ✓ · UL Listed ✓
Lead-Free Solder Alloys We Use
We select lead-free solder alloys based on your application requirements — balancing cost, wetting performance, joint reliability, and thermal cycling resistance. All alloys below comply with RoHS 3 (Directive 2015/863) and REACH regulations.
| Alloy | Composition | Melting Range | Key Properties | Typical Application |
|---|---|---|---|---|
| SAC305 | Sn96.5 / Ag3.0 / Cu0.5 | 217–220°C | Industry standard, excellent wetting, good thermal fatigue | General SMT reflow, most common lead-free alloy |
| SAC307 | Sn99.0 / Ag0.3 / Cu0.7 | 217–227°C | Lower silver content reduces cost, acceptable for non-critical joints | Cost-sensitive consumer electronics |
| SN100C | Sn99.25 / Ag0.25 / Cu0.5 / Ni0.05 + Ge | 227°C | Flat bright joints, excellent fluidity, reduced copper dissolution | Wave soldering, THT assembly |
| SnAg3.5 | Sn96.5 / Ag3.5 | 221°C | High reliability, superior thermal fatigue resistance | Automotive, industrial, harsh-environment electronics |
| SnCu0.7 (N₂) | Sn99.3 / Cu0.7 | 227°C | Lowest cost lead-free wave soldering alloy, requires nitrogen atmosphere | High-volume wave soldering for THT |
SAC305 remains our default for SMT reflow applications due to its proven reliability and broad industry acceptance. For through-hole wave soldering, SN100C is preferred for its superior fluidity and reduced copper pad dissolution.
Lead-Free Compatible Surface Finishes
The PCB surface finish you choose directly affects lead-free solder joint quality, shelf life, and cost. Not all finishes perform equally with SAC305 and other lead-free alloys. The table below helps you select the right finish for your lead-free project.
| Surface Finish | Shelf Life | Solderability | Flatness | Cost | Best For |
|---|---|---|---|---|---|
| ENIG | 12+ months | Excellent | Excellent (flat) | High | BGA, QFN, fine-pitch SMT — best overall choice for lead-free |
| OSP | 3–6 months | Good (first reflow only) | Good | Low | Cost-sensitive single-side SMT boards — not suitable for double-sided or wave soldering |
| HASL Lead-Free | 12+ months | Good | Poor (uneven) | Low | THT and mixed-technology boards — avoid for fine-pitch BGA |
| Immersion Silver | 6–12 months | Very Good | Excellent | Medium | High-frequency/RF boards, fine-pitch SMT — requires anti-tarnish packaging |
| Immersion Tin | 6–12 months | Good | Excellent | Medium | Press-fit connectors, fine-pitch SMT — tin whisker risk, evaluate for reliability-critical use |
Recommendation: For most lead-free SMT assembly with BGA or fine-pitch components, ENIG is the safest choice due to its flat surface and excellent solderability across multiple reflow cycles. For cost-sensitive THT boards, HASL Lead-Free is acceptable. Contact us to discuss your specific finish requirements.
RoHS & REACH Compliance
Every lead-free assembly project we deliver comes with full compliance documentation. We maintain material declarations and third-party test reports for all solder materials, fluxes, and surface finishes used in production.
- RoHS 3 Compliance (2015/863): All solder alloys, fluxes, and surface finishes (HASL lead-free, ENIG, OSP) comply with the latest RoHS 3 directive, restricting 10 substances including lead (Pb), mercury, cadmium, and phthalates.
- REACH Compliance (EC 1907/2006): We provide SVHC (Substances of Very High Concern) declarations for all materials. No substances on the current REACH SVHC candidate list are intentionally added to our solder pastes or fluxes.
- Conflict Minerals (Dodd-Frank §1502): Tin, tungsten, tantalum, and gold in our solder materials are sourced from conflict-free smelters certified under the RMI (Responsible Minerals Initiative) program.
| Document | Content | Provided With |
|---|---|---|
| Material Declaration (MD) | Full composition of solder alloys, fluxes, finishes | Every production order |
| RoHS Compliance Certificate | Declaration of conformity to RoHS 3 | On request |
| REACH SVHC Declaration | Statement of SVHC content per candidate list | On request |
| Third-Party Test Report | SGS or Intertek XRF testing results | On request |
| IPC Certificate of Conformity | J-STD-001 compliance statement | Every production order |
All compliance documents are provided free of charge with your production order. Need a specific report for your customer? Contact us before production to ensure the required testing is included.
Lead-Free Reflow Soldering Profile
Lead-free reflow requires higher peak temperatures than tin-lead soldering — typically 240–260°C versus 210–230°C. Our reflow profiles are engineered per JEDEC J-STD-020 and IPC-7530 standards to ensure proper wetting while minimizing thermal stress on components and laminate.
| Zone | Temperature Range | Dwell Time | Purpose |
|---|---|---|---|
| Preheat (Zone 1–3) | 25 → 150°C | 60–90 sec | Evaporate solvent from flux; activate flux chemistry; prevent thermal shock to components |
| Soak / Thermal Stabilization (Zone 4–5) | 150 → 200°C | 60–120 sec | Uniform board temperature; activate flux; reduce ΔT across PCB to prevent tombstoning |
| Reflow Peak (Zone 6–7) | 240 – 260°C (peak) | 30–60 sec above 217°C (liquidus) | Melt solder alloy; form metallurgical bond; ensure proper wetting and fillet formation |
| Cooling (Zone 8) | 260 → 70°C | 60–90 sec (4–6°C/sec cooling rate) | Solidify solder joints; controlled cooling prevents grain coarsening and improves joint reliability |
Critical parameter: Peak temperature must remain between 240–260°C and time-above-liquidus (TAL) must be 30–60 seconds. Exceeding 260°C risks component damage; falling below 240°C risks cold solder joints and insufficient wetting.
Lead-Free vs Leaded Assembly: Key Differences
Understanding the differences between lead-free and traditional tin-lead assembly helps you make informed decisions for your project. The table below summarizes the critical technical and commercial differences.
| Parameter | Lead-Free (SAC305) | Leaded (Sn63Pb37) | Impact |
|---|---|---|---|
| Melting Point | 217–220°C | 183°C | Lead-free requires +30–40°C higher reflow temps |
| Reflow Peak | 240–260°C | 210–230°C | Components must rated for 260°C lead-free profile |
| Wetting | Slower wetting, duller appearance | Fast wetting, bright shiny joints | Lead-free joints appear different but are equally reliable when properly formed |
| Surface Finish Compatibility | ENIG, OSP, HASL lead-free, Imm Silver, Imm Tin | HASL tin-lead | Lead-free requires compatible surface finishes |
| Thermal Fatigue | Better in thermal cycling | Better in vibration/mechanical stress | Application-dependent — lead-free preferred for thermal cycling, leaded for mechanical stress |
| Cost | +15–30% (higher silver content, higher temp equipment) | Lower | Lead-free carries a cost premium |
| RoHS/REACH | ✅ Compliant | ❌ Non-compliant (contains lead) | Lead-free required for EU, California, and most global markets |
| Rework Difficulty | Harder — higher melt temp, faster oxidation | Easier — lower melt temp, better wetting | Lead-free rework requires more skill and nitrogen assistance |
Our Lead-Free Assembly Capabilities
Our lead-free PCB assembly facility is equipped for both SMT and through-hole processes, supporting prototype to mid-volume production with full RoHS compliance at every stage.
PCB Specifications：
| Parameter | Capability |
|---|---|
| Max PCB Size | 535 × 840 mm |
| Layer Count | 1–32 layers |
| Board Thickness | 0.1–8.0 mm |
| Surface Finish | ENIG, OSP, HASL Lead-Free, Immersion Silver, Immersion Tin |
| Min Trace/Space | 2 / 2 mil |
| Min Hole Size | 0.15 mm (mechanical drill) |
Assembly Capability：
| Parameter | Capability |
|---|---|
| SMT Component Range | 01005 (0.4 × 0.2 mm) to 50 × 50 mm |
| THT Component Types | Axial, Radial, DIP, SIP, Custom |
| Placement Speed | Up to 36,000 CPH |
| Reflow Zones | 10-zone lead-free profile |
| Wave Soldering | Lead-free wave with N₂ atmosphere |
| Inspection | 100% AOI + X-ray (AXI) for BGA/QFN |
| Daily Capacity | Up to 5 million solder joints |
ISO 9001:2015
Quality management system certified for lead-free assembly processes
IATF 16949:2016
Automotive quality standard — lead-free assemblies for vehicle electronics
UL Listed
UL certification for lead-free PCB assemblies (E-number on file)
Lead-Free Solder Joint Quality Standards
Lead-free solder joints look different from tin-lead joints — they are typically duller and less shiny. This is normal and does not indicate a defect. We inspect all lead-free assemblies to IPC-A-610 Acceptability of Electronic Assemblies standards, with full documentation available.
- IPC-A-610 Class 2 & 3: All lead-free solder joints inspected to IPC-A-610. Class 2 (dedicated service electronics) is our default; Class 3 (high-reliability) is available for automotive, medical, and aerospace applications.
- J-STD-001 Soldering Requirements: Soldering processes and materials certified to J-STD-001, covering material requirements, process controls, and acceptance criteria for lead-free soldered connections.
- 100% AOI Inspection: Automated Optical Inspection (AOI) on every assembly, checking solder volume, fillet shape, bridging, tombstoning, and component placement for both SMT and THT joints.
- X-Ray Inspection (AXI): For BGA, QFN, and hidden-joint components, X-ray inspection verifies solder ball integrity, void percentage (<25% per IPC-7095), and complete wetting under hidden leads.
⚠️ Visual note for lead-free joints: Lead-free solder joints naturally appear grainy, dull, or matte — this is NOT a defect. In tin-lead soldering, dull joints indicated problems; in lead-free soldering, dullness is normal and expected. Shiny, bright lead-free joints may actually indicate a process problem (insufficient thermal profile).
Industries & Applications Served
Lead-free PCB assembly is not one-size-fits-all. Different industries demand different reliability classes, traceability levels, and compliance documentation. We tailor our lead-free processes to meet your industry’s specific requirements.
Consumer Electronics
High-volume, cost-optimized lead-free assembly to IPC-A-610 Class 2. Ideal for smart home devices, wearables, and IoT products targeting global markets.
Automotive Electronics
IATF 16949 certified lead-free assembly to IPC-A-610 Class 3. Thermal cycling reliability, full material traceability, and PPAP documentation available for vehicle ECUs and sensor modules.
Medical Devices
ISO 9001 quality system with full traceability for lead-free medical PCBs. Cleanroom-compatible assembly, conformal coating, and documented processes for patient-connected and diagnostic equipment.
Industrial & IoT
Harsh-environment lead-free assembly for industrial control boards, power management modules, and connected sensors. Conformal coating and extended thermal cycling testing available.
Frequently Asked Questions
What is lead-free PCB assembly?
Lead-free PCB assembly is the process of soldering electronic components to a printed circuit board using solder alloys that contain no lead (Pb), typically tin-silver-copper (SAC) alloys. It is required for compliance with the EU RoHS Directive, which restricts hazardous substances including lead in electronic products.
Which lead-free solder alloy does JHYPCB use?
We primarily use SAC305 (Sn96.5/Ag3.0/Cu0.5) for SMT reflow soldering and SN100C for through-hole wave soldering. Alternative alloys such as SAC307, SnAg3.5, and SnCu0.7 (nitrogen wave) are available for specific applications. We can also accommodate customer-specified alloys upon request.
Is lead-free PCB assembly RoHS and REACH compliant?
Yes. All our lead-free solder alloys, fluxes, and surface finishes comply with RoHS 3 (Directive 2015/863) and REACH (EC 1907/2006). We provide material declarations, RoHS compliance certificates, REACH SVHC declarations, and third-party SGS/Intertek test reports with your production order.
Can you assemble a board with both lead-free and leaded solder?
Yes, but this requires a sequential process: lead-free reflow first (higher temperature), then leaded wave or hand soldering for specific through-hole components. This is sometimes used when certain components are not rated for 260°C lead-free reflow. We evaluate each mixed-alloy requirement case by case.
What is the minimum order quantity for lead-free PCB assembly?
There is no strict minimum — we accept orders from a single prototype board to high-volume production. However, for very small quantities, a setup fee may apply. Contact us with your BOM and Gerber files for a detailed quote.
How do you ensure lead-free solder joint quality?
We inspect all lead-free assemblies to IPC-A-610 (Class 2 or 3) standards using 100% Automated Optical Inspection (AOI) for SMT joints and X-ray inspection (AXI) for BGA/QFN hidden joints. Lead-free solder joints naturally appear duller than tin-lead joints — this is normal and does not indicate a quality issue.
