8-Layer Hybrid High-Frequency PCB – RO4003C (Rogers) + S1000-2M (Shengyi) with Blind Vias & Resin-Filled Vias

Product Description

Hybrid High-Frequency PCB Solution – RO4003C + S1000-2M 8-Layer Custom Board

 

Q: What is this hybrid PCB solution, and what does it achieve?

A: This solution combines Rogers RO4003C (a high-frequency hydrocarbon ceramic laminate) with S1000-2M (a high-performance FR-4–type material from Shengyi) in a single 8-layer hybrid stack-up. The top and bottom layers use 0.203mm RO4003C for optimal RF signal integrity, while the inner core uses S1000-2M for cost-effective, reliable multilayer routing.

 

 

The reference product is specified as:

 

• 8 layers, 1.6mm finished thickness
• Outer layers: 1 oz copper | Inner layers: 0.5 oz / 1 oz (mixed)
• Surface finish: ENIG (Immersion Gold)
• Blind vias: L1–L2 and L7–L8
• Resin-filled vias: 0.2mm, 0.25mm, 0.35mm
• Green solder mask, white silkscreen, 273mm × 185mm panel

 

This hybrid design delivers high-frequency performance where it matters (outer layers) and cost-effective, high-density routing inside – ideal for RF front-ends, 5G small cells, and radar modules.

 

Key Takeaways

	Key Highlight	Description
①	Hybrid Stack-Up	Combines Rogers RO4003C (RF-grade) and Shengyi S1000-2M (high-Tg FR-4) in one board – balancing performance and cost.
②	RF-Optimized Outer Layers	Top and bottom RO4003C layers provide low Dk (3.38±0.05) and low Df (0.0027 @ 10GHz) for clean signal launch and termination.
③	High-Thermal Core	S1000-2M core offers Tg = 185°C (DMA), Td = 355°C, and excellent CAF/IST reliability – ideal for high-layer-count inner routing.
④	Advanced HDI Capabilities	Supports blind vias (L1–L2, L7–L8) and resin-filled vias (0.2/0.25/0.35mm) – enabling dense BGA breakout and impedance control.
⑤	RoHS & Lead-Free Compatible	Both materials are fully compatible with lead-free assembly processes (peak reflow >260°C).
⑥	Proven Reliability	S1000-2M has passed IST >2000 cycles, CAF >1000 hours, and 6× 260°C reflow – ensuring long-term field performance.

 

 

1. Material Overview – RO4003C (Rogers)

RO4003C is a hydrocarbon ceramic laminate from Rogers Corporation, specifically designed for high-frequency RF/microwave applications. It bridges the performance gap between PTFE-based materials and standard FR-4, offering:

 

Low and stable Dk – 3.38 ± 0.05 (process) / 3.55 (design) from 8–40 GHz

 

Low dissipation factor – 0.0027 @ 10GHz, 0.0021 @ 2.5GHz

 

Very low Dk temperature coefficient – +40 ppm/°C (stable over -50°C to 150°C)

 

High Tg > 280°C (TMA) and Td = 425°C – exceptional thermal robustness

 

Low Z-axis CTE – ~46 ppm/°C – ensures reliable plated through-holes

 

FR-4 process compatible – no sodium etch or special via prep required

 

 

Key Electrical Properties (RO4003C):

Property	Value	Condition
Dielectric Constant (Process Dk)	3.38 ± 0.05	10 GHz / 23°C
Dielectric Constant (Design Dk)	3.55	8–40 GHz
Dissipation Factor (Df)	0.0027 / 0.0021	10 GHz / 2.5 GHz
Tεr (Thermal Coefficient of Dk)	+40 ppm/°C	-50°C to 150°C
Volume Resistivity	1.7 × 10¹⁰ MΩ·cm	COND A
Surface Resistivity	4.2 × 10⁹ MΩ	COND A
Electrical Strength	31.2 kV/mm (780 V/mil)	0.51mm
Moisture Absorption	0.06%	48h immersion @50°C

 

 

Mechanical & Thermal (RO4003C):

Property	X / Y / Z	Value
Tensile Modulus	X / Y	19,650 / 19,450 MPa (2,850 / 2,821 ksi)
Tensile Strength	X / Y	139 / 100 MPa (20.2 / 14.5 ksi)
Flexural Strength	–	276 MPa (40 kpsi)
CTE	X / Y / Z	11 / 14 / 46 ppm/°C (-55 to 288°C)
Tg (TMA)	–	>280°C
Td (TGA)	–	425°C
Thermal Conductivity	–	0.71 W/m·K
Copper Peel Strength	–	1.05 N/mm (6.0 pli)

 

Standard Thicknesses Available: 0.008" (0.203mm), 0.012", 0.016", 0.020", 0.032", 0.060" – our design uses 0.203mm (8 mil) for outer layers.

 

Applications: Automotive radar (77GHz), 5G mmWave antennas, point-to-point radios, satellite communications, test & measurement equipment.

 

 

2. Material Overview – S1000-2M (Shengyi)

S1000-2M is a high-performance, high-Tg FR-4–type laminate from Shengyi Technology, designed for multilayer boards requiring excellent thermal reliability and CAF resistance. It is widely used in:

 

High-layer-count backplanes and server boards

 

Automotive and industrial electronics

 

Base station equipment

 

Any application requiring lead-free soldering compatibility and long-term reliability

 

Key Properties (S1000-2M):

Property	Condition	Spec	Typical Value
Tg (DMA)	–	≥180°C	185°C
Td (5% wt loss)	–	≥340°C	355°C
CTE (Z-axis, pre-Tg)	–	≤60 ppm/°C	41 ppm/°C
CTE (Z-axis, post-Tg)	–	≤300 ppm/°C	208 ppm/°C
CTE (Z-axis, 50–260°C)	–	≤3.0%	2.40%
T260 / T288 / T300	TMA	≥30 / ≥5 / ≥2 min	60 / 30 / 15 min
Thermal Stress (288°C solder dip)	–	>10s, no delam	>100s, no delam
Peel Strength (1 oz)	288°C/10s	≥1.05 N/mm	1.3 N/mm
Water Absorption	D-24/23	≤0.5%	0.08%
CTI (Comparative Tracking Index)	IEC60112	PLC3 (175–250V)	PLC3 (200V)
Volume Resistivity	After moisture / E-24/125	≥10⁶ / ≥10³ MΩ·cm	6.79×10⁷ / 2.19×10⁸
Surface Resistivity	After moisture / E-24/125	≥10⁴ / ≥10³ MΩ	3.16×10⁶ / 2.24×10⁷
Dielectric Constant (Dk)	@1GHz / @1MHz	– / ≤5.4	4.6 / 4.9
Dissipation Factor (Df)	@1GHz / @1MHz	– / ≤0.035	0.018 / 0.015
Flammability	UL94	V-0	V-0

 

 

Reliability Validation (S1000-2M):

 

24-layer board (0.13mm core, 4.0mm total thickness, 0.35mm min hole, aspect ratio 11.5:1) – passed 5× 260°C lead-free reflow.

 

IST (Interconnect Stress Test) – 20-layer board, >2000 power cycles (room temp to 150°C), no failure.

 

CAF (Conductive Anodic Filament) Test – 20-layer, TH–TH 16/20 mil spacing, >1000 hours at 65°C/87%RH/100V DC, passed.

 

 

3. Custom PCB – 8-Layer Hybrid Stack-Up

This board represents our capability to integrate dissimilar materials into a single, high-reliability PCB with advanced HDI features.

 

Basic Specifications

Item	Specification
Layer Count	8 layers
Stack-Up Type	Hybrid – Top/Bottom: RO4003C (0.203mm); Inner Core: S1000-2M
Finished Board Thickness	1.6mm
Outer Layer Copper	1 oz (both top and bottom)
Inner Layer Copper	Mixed – 0.5 oz / 1 oz (designed per signal/power requirements)
Surface Finish	ENIG (Immersion Gold) – excellent for fine-pitch components and wire bonding
Solder Mask / Legend	Green solder mask / White silkscreen (both sides)
Panel Size	273mm × 185mm (1 piece, including manufacturing borders)

 

 

Advanced HDI & Via Features

Feature	Detail	Benefit
Blind Vias	L1–L2, L7–L8	Eliminates stub effects on RF layers; improves signal integrity
Resin-Filled Vias	0.2mm, 0.25mm, 0.35mm diameters	Provides flat, solderable surfaces; enables via-in-pad design for BGA routing
Mixed Copper Weights	0.5 oz inner / 1 oz outer	Optimizes impedance control (inner) and current capacity (outer)
Hybrid Material Bonding	RO4003C + S1000-2M with compatible prepreg	Balances RF performance and mechanical strength across the board

 

 

Hybrid Stack-Up

 

This configuration ensures that critical RF paths reside entirely within RO4003C, while the bulk of digital and power layers use S1000-2M – giving you the best of both worlds.

 

 

Comparison Table – RO4003C vs. S1000-2M vs. Typical FR-4

Parameter	RO4003C (Rogers)	S1000-2M (Shengyi)	Standard FR-4 (High-Tg)
Dk @ 1GHz / 10GHz	3.38 (10GHz) / 3.55 (8–40GHz)	~4.6 (1GHz) / –	~4.2–4.5
Df @ 10GHz / 1GHz	0.0027 (10GHz)	0.018 (1GHz)	0.015–0.020
Tg (DMA/TMA)	>280°C (TMA)	185°C (DMA)	~170–180°C
Td (TGA)	425°C	355°C	~340°C
CTE Z-axis (pre/post Tg)	~46 ppm/°C	41 / 208 ppm/°C	~50–70 / 250–350
Thermal Conductivity	0.71 W/m·K	–	~0.3–0.5
Moisture Absorption	0.06%	0.08%	~0.3–0.5%
Process Compatibility	FR-4 compatible	FR-4 standard	FR-4 standard
Primary Application	RF/mmWave front-end	High-layer-count digital/backplane	General digital
Relative Cost	Higher	Mid	Low

 

 

Application Areas – Where This Hybrid PCB Excels

• 5G Small Cells / Base Stations
• Automotive Radar (76–81GHz)
• Phased-Array Antennas
• Aerospace & Defense
• High-Speed Digital + RF Modules

 

 

Q1: Why choose a hybrid stack-up instead of all-RO4003C?
A: Cost optimization. RO4003C is significantly more expensive than FR-4-type materials. By using RO4003C only on the outer layers where RF performance matters, and S1000-2M for the inner layers, we reduce material cost while maintaining critical RF performance.

 

 

Q2: Are RO4003C and S1000-2M compatible in terms of lamination?
A: Yes. Both materials are thermoset systems compatible with standard FR-4 lamination cycles. We use transition prepreg layers to ensure reliable bonding between the different core materials.

 

 

Q3: Can you support impedance-controlled designs on this hybrid board?
A: Absolutely. We can calculate and control differential/single-ended impedances on both RO4003C and S1000-2M layers based on your stack-up and trace geometry requirements.

 

 

Q4: What is the minimum via diameter you can drill and fill?
A: We support mechanical drilling down to 0.15mm and resin filling for vias as small as 0.2mm (as specified in this design: 0.2, 0.25, 0.35mm).

 

 

Q5: Is ENIG (Immersion Gold) suitable for RF applications?
A: Yes. ENIG provides a flat, solderable surface and good corrosion resistance. For very high-frequency (mmWave) applications, some designers prefer immersion silver to avoid the nickel layer, but ENIG is widely accepted for most RF designs up to 40GHz.

 

 

Q6: What is the lead time for this hybrid 8-layer board?
A: Typical prototype lead time is 10–15 working days for this stack-up with blind vias and resin filling. Volume production lead time can be shortened with advance material sourcing.

 

 

Q7: Do you provide stack-up design assistance?
A: Yes. Our engineering team can help you define layer assignments, calculate impedance, and optimize the hybrid stack-up for manufacturability and signal integrity.

 

 

Q8: What are the storage conditions for S1000-2M prepreg?
A: Short-term (<3 months): <23°C, <50% RH. Long-term (up to 6 months): 5°C. Always keep wrapped in moisture-proof material and avoid UV/strong light.

 

 

Q9: Can you build this board with LoPro foil on RO4003C for lower loss?
A: Yes. Rogers offers RO4003C with LoPro® (reverse-treated) foil for reduced insertion loss. Please specify this requirement in your inquiry.

 

 

Q10: Is this design compliant with IPC standards?
A: Yes. RO4003C conforms to IPC-4103 /10, and S1000-2M meets applicable IPC-4101 specifications. Our manufacturing process is IPC Class 2/3 compliant.

 

 

Contact Us

As a specialized PCB supplier based in China, we have extensive experience with hybrid high-frequency materials and complex HDI processes. Whether you need a prototype or volume production, we provide:

 

Full material traceability

Impedance testing (TDR)

X-ray inspection for blind vias

Electrical testing (flying probe / fixture)

Quick-turn services available

 

For technical inquiries, quotation requests, or design review support, please contact our sales team directly. We look forward to helping you bring your high-frequency designs to life.