Shengyi S7136 PCB: Properties, Design & Cost

What Is the Shengyi S7136 PCB Laminate?

Shengyi S7136 is a glass-reinforced hydrocarbon ceramic–filled laminate designed for RF and microwave circuits up to roughly 10 GHz. A Shengyi S7136 PCB provides a dielectric constant (Dk) of 3.60 ± 0.05 at 10 GHz, a dissipation factor (Df) of 0.0035 at the same frequency, and standard FR-4–compatible processing—meaning no special drill bits, plasma desmear or exotic bonding cycles. For cost-sensitive designs that need better electrical performance than FR-4 but cannot justify premium PTFE pricing, the S7136 PCB is one of the most practical choices available from a domestic Chinese laminate supplier.

Key Electrical and Mechanical Properties of Shengyi S7136 PCB

The table below collects the parameters most relevant to RF PCB design. All electrical values are at 10 GHz unless noted.

A Tg above 200 °C and Td above 380 °C mean S7136 handles multiple lead-free reflow cycles without delamination—an important practical advantage over some older thermoset laminates. The z-axis CTE of 35 ppm/°C is moderate; for boards thicker than about 2.0 mm with many plated vias, via reliability should be checked against IPC-6012 Class 3 requirements.

Where S7136 Fits: Dk and Df in Context

Understanding where a Shengyi S7136 PCB sits relative to other common RF laminates helps you decide whether it is over- or under-specified for a given design. The comparison below focuses on the properties that directly affect insertion loss and impedance stability.

S7136’s Dk of 3.60 and Df of 0.0035 are remarkably close to RO4350B (Dk 3.48, Df 0.0037). The main trade-off is a slightly higher Dk, which narrows microstrip traces by a few mils for the same impedance, and a tighter Dk tolerance on Rogers material (±0.05 for S7136 versus ±0.05 for RO4350B—essentially equivalent). For many designs below 6 GHz, the performance gap is negligible; above 6 GHz, cumulative insertion-loss differences begin to matter on longer trace runs. For a deeper look at how these two brands compare across their product lines, see our Rogers vs Shengyi comparison.

Shengyi S7136 PCB Material Selector

Not sure whether S7136, S7136H or another Shengyi grade is the best match for your frequency, loss budget and stackup? Enter your operating frequency and target Dk range below to see which Shengyi laminates qualify.

If the selector returns S7136 for your frequency band but you need a halogen-free BOM, switch to S7136H—it shares the same Dk but adds roughly 15 % to the Df and a small cost premium. For applications above 24 GHz, the tool will likely steer you toward Shengyi’s SCGA-500GF PTFE laminate, which drops Df below 0.0015.

Fabrication and Processing Notes

Drilling

S7136 uses woven-glass reinforcement with a ceramic filler, so standard carbide drill bits work fine at normal feed rates. Drill-to-copper registration of ±75 µm (±3 mil) is achievable on most production lines. Aspect ratios up to 10:1 are feasible without back-drilling, though for multilayer RF builds above 8 layers the fabricator should confirm via reliability by thermal cycling to IPC-TM-650 2.6.26.

Lamination and Hybrid Stackups

S7136 bonds well with standard FR-4 prepreg (e.g., Shengyi S1000-2M) in hybrid stackups. A common architecture places S7136 cores on the outer RF layers and FR-4 cores in the digital inner layers, cutting material cost by 30–50 % compared with an all-S7136 build. Press parameters are similar to high-Tg FR-4: typical peak temperature 190–210 °C, dwell 60–90 minutes, pressure 250–350 psi. No nitrogen atmosphere is needed.

Surface Finish

ENIG, immersion silver and OSP are all compatible. For RF front-end boards where conductor loss dominates, immersion silver offers slightly lower surface roughness than ENIG. If the design requires wire bonding, ENIG with ≥3 µin gold is the safer choice. Consult the RF laminate thickness chart when specifying core and prepreg combinations to hit your target stackup height.

Etching Tolerances

Controlled-impedance lines on a Shengyi S7136 PCB hold ±10 % impedance tolerance routinely, and ±7 % with tight process controls—comparable to what fabricators achieve on RO4350B. Trace width tolerance of ±0.5 mil (±12.7 µm) is standard for 1 oz copper after etch.

Typical Applications for Shengyi S7136 PCB Designs

S7136 is used most heavily in designs where RF performance must be “good enough” while keeping the BOM competitive:

• Wi-Fi 6 / 6E access points (2.4–6 GHz): Antenna feed networks and PA matching sections on S7136 outer layers, baseband on FR-4 inner layers.
• GPS / GNSS receivers (1.2–1.6 GHz): Patch antenna substrates where Dk stability over temperature directly affects center-frequency drift.
• 5G sub-6 GHz small cells (3.3–4.2 GHz): Filter and duplexer boards where Df of 0.0035 keeps passband insertion loss within budget.
• Automotive V2X modules (5.9 GHz): Cost pressure is extreme; S7136 delivers adequate loss at a fraction of Rogers pricing.
• Frequency synthesizer boards: PLL loop-filter routing benefits from the low moisture absorption (≤ 0.10 %) that keeps Dk stable in humid environments.

Above roughly 10 GHz, cumulative dielectric loss on S7136 starts to hurt. For 24 GHz or 77 GHz radar, engineers typically move to PTFE-based or LCP substrates where Df drops below 0.002. Understanding when FR-4 fails and a high-frequency laminate is needed will help you draw the line for your own frequency and trace-length budget.

Cost Positioning and Domestic vs. Offshore Trade-Offs

One of the Shengyi S7136 PCB’s strongest selling points is its cost structure. As a Shengyi product, it is manufactured in mainland China and widely stocked by Asian fabricators, which means short lead times (typically 1–2 weeks for standard cores) and competitive panel pricing. Compared with Rogers RO4350B, expect S7136 panels to cost roughly 40–60 % less in equivalent thickness and copper weight. For more detail on RF laminate pricing across brands, our RF laminate price guide breaks down the drivers panel by panel.

When sourcing S7136 PCBs, the build location matters as much as the material itself. Use the calculator below to estimate the landed cost difference between domestic (North American or European) fabrication and offshore (Asian) fabrication for your board parameters.

For a typical 4-layer S7136 board, 1.6 mm thick, 100 × 100 mm, in quantities of 100–500 pieces, offshore fabrication often comes in 35–55 % below domestic pricing. However, domestic builds may be justified when you need IPC-6012 Class 3 certification with full coupon testing, faster engineering iterations, or when ITAR or defense-related restrictions apply. Factor in shipping time (3–5 days air, 25–35 days sea) and import duties when comparing total landed cost.

Design Tips for Shengyi S7136 PCB Layouts

Impedance Targeting

With Dk 3.60 on a 0.508 mm (20 mil) core and 1 oz copper, a 50 Ω microstrip line is approximately 1.07 mm (42 mil) wide. That is slightly narrower than the same impedance on RO4350B (Dk 3.48), where the trace would be about 1.12 mm. Always run a 2D field solver with the manufacturer’s actual Dk value rather than relying on handbook approximations—Dk can shift by ±0.03 between production lots.

Grounding and Via Fencing

At 5–6 GHz, via spacing for ground stitching should stay below λ/10 in the dielectric—roughly 2.6 mm for S7136 at 6 GHz. Tighter spacing (λ/20) is preferred around coupled-line filters and along microstrip-to-stripline transitions to suppress parallel-plate modes.

Moisture Sensitivity

S7136’s moisture absorption of ≤ 0.10 % is low for a non-PTFE laminate. Still, bake panels at 120 °C for 2–4 hours before lamination if they have been stored unsealed for more than 72 hours—absorbed moisture can cause measling during reflow and shift Dk by up to 0.05 in extreme cases.

Thermal Management

Thermal conductivity of 0.60 W/m·K is about 1.5× that of standard FR-4 (≈ 0.35 W/m·K) but far below alumina ceramic (≈ 25 W/m·K) or aluminum nitride substrates (170 W/m·K). For PA stages dissipating more than 2–3 W, add thermal vias under the device pad and consider a metal-backed variant or a copper coin insert.

S7136 vs. RO4350B: When to Choose Which

This is the comparison engineers make most often, so here is a direct verdict:

• Choose a Shengyi S7136 PCB when your operating frequency is below 6 GHz, trace runs are short (under ~100 mm), cost is a primary driver, and you are building in volume (>500 pcs). The electrical performance gap at these frequencies is minimal.
• Choose RO4350B when you need tighter lot-to-lot Dk consistency for narrow-band filters, your design operates between 6 and 20 GHz, or your customer’s qualification data is already baselined on Rogers material and requalification cost exceeds the material savings.
• Consider neither above 20 GHz—move to a low-loss PTFE or LCP laminate where Df is below 0.002.

For additional reading on how the broader Shengyi high-frequency family stacks up, including S7136H and SCGA-500GF, see our family overview.

Quality and Standards Compliance

S7136 carries UL 94 V-0 flammability certification. Shengyi publishes comparable test-method references aligned with IPC-TM-650 and IPC-4101 slash-sheet conventions. When specifying an S7136 PCB on a drawing, call out:

• Dk and Df at the design frequency, not just “S7136.”
• Core thickness and copper weight per IPC-4101.
• Impedance tolerance (±10 % standard, ±7 % tight).
• Workmanship class per IPC-6012 (Class 2 for commercial, Class 3 for high-reliability).

Frequently Asked Questions

Is a Shengyi S7136 PCB a drop-in replacement for Rogers RO4350B?

Electrically it is close—Dk 3.60 vs. 3.48, Df 0.0035 vs. 0.0037—but the higher Dk means trace widths differ by 2–4 %. A board designed for RO4350B needs an impedance re-simulation before switching to S7136, and the mechanical stackup thicknesses may not match exactly.

What is the maximum usable frequency for S7136?

Shengyi rates S7136 for applications up to about 10 GHz. In practice, many designers use it successfully at 5.8–6 GHz (Wi-Fi, V2X) with acceptable loss. Above 10 GHz, dielectric loss rises noticeably and PTFE-based materials become a better choice.

Can S7136 be used in multilayer hybrid stackups with FR-4?

Yes. S7136 cores laminate well with standard epoxy prepregs. A common 6-layer hybrid places S7136 on layers 1–2 and 5–6 (RF) with FR-4 on layers 3–4 (digital/power). Press cycle parameters are compatible.

Does S7136 meet RoHS and halogen-free requirements?

S7136 is RoHS-compliant. It is not halogen-free; for halogen-free compliance (IEC 61249-2-21), use the S7136H variant, which shares the same Dk but has a slightly higher Df of 0.0040.

What lead time should I expect for S7136 cores?

Standard thicknesses (0.508 mm and 0.762 mm in 1 oz copper) are typically stocked by major Asian fabricators with 1–2 week lead times. Non-standard thicknesses or 2 oz copper may add 3–4 weeks.