Arlon AD vs DiClad: Key Differences Every RF Engineer Should Know

If you’ve been specifying Arlon microwave laminates for any length of time, you’ve almost certainly had this moment: you’re trying to choose between the AD Series and DiClad Series, and both seem to be PTFE-based woven fiberglass materials sitting in the same general Dk neighborhood. The datasheets look similar at a glance. The fabrication guidelines share the same document. So what’s actually different between them, and when does that difference genuinely matter for your design?

The short answer is: the Arlon AD vs DiClad choice comes down to ceramic loading, Dk range, CTE behavior, and the performance tier you need. This guide unpacks those differences with enough technical depth to make the right call for your specific application — whether you’re designing a 5G base station antenna panel, a radar feed network, or a filter for a satellite payload.

What Are the Arlon AD Series and DiClad Series, Really?

Both the AD Series and DiClad Series are woven fiberglass-reinforced PTFE composite laminates made by Arlon (now under the Rogers corporate umbrella following the 2014 acquisition). Both families rely on the same fundamental design principle: adjusting the ratio of fiberglass to PTFE resin to tune the dielectric constant and mechanical properties. More fiberglass means a higher Dk and better dimensional stability. More PTFE means a lower Dk and better loss performance.

That’s where the similarity ends.

H3: The AD Series — PTFE Plus Ceramic Filler

The AD Series combines the excellent low-loss electrical properties of PTFE resin with the enhanced value of cost-effective heavier fiberglass styles, and the higher weight ratio of fiberglass to PTFE resin yields laminates with greater dimensional stability than is normally expected of PTFE-based substrates. But the key ingredient that distinguishes the modern AD Series — particularly the A-suffix grades like AD255A, AD260A, AD300A, and AD320A — is the addition of micro-dispersed ceramic filler in the PTFE matrix.

That ceramic loading is not cosmetic. It directly suppresses Z-axis thermal expansion, improving plated through-hole barrel fatigue life. It increases thermal conductivity compared to pure PTFE/glass laminates. It pushes the achievable Dk range higher — all the way to 10.2 in the AD1000 — without switching to an entirely different resin system. And in the newer “A” grades, it enables tighter Dk tolerance control by providing a more uniform dielectric composition across the panel.

H3: The DiClad Series — Pure PTFE/Fiberglass Without Ceramic

The DiClad family takes a different path. DiClad laminates are woven fiberglass/PTFE composite materials for use as printed circuit board substrates, using precise control of the fiberglass/PTFE ratio. The coated fiberglass plies in DiClad materials are aligned in the same direction, and cross-plied versions of many of these materials are available as Arlon CuClad materials.

There is no ceramic filler in DiClad laminates. The dielectric properties are controlled entirely through the fiberglass-to-PTFE content ratio, and the fiberglass plies run in the same direction — which is an important structural distinction from the cross-plied CuClad family. This unidirectional ply arrangement affects in-plane isotropy and how the material behaves during precision etching and inner layer processing.

The controlled fiberglass and PTFE content ratio enables DiClad laminates to offer a range of low dielectric constant (Dk) values. Higher PTFE content provides a lower Dk and loss tangent, while higher fiberglass content provides better dimensional stability and registration. At the extreme low-Dk end, by using fewer plies of woven fiberglass and a higher ratio of PTFE content, the DiClad 870 and DiClad 880 laminates offer lower dielectric constants and dissipation factors at a similar thickness to other laminates in the DiClad series.

Full Electrical Properties Comparison: AD Series vs DiClad Series

The table below puts the key grades from each family side by side so you can see exactly where they overlap and where they diverge.

Material	Family	Dk @ 10 GHz	Df @ 10 GHz	Ceramic Filler	Fiberglass Orientation	Primary Strength
AD250A	AD Series	2.50 ± 0.04	~0.0016	Yes (micro-dispersed)	Woven (unidirectional)	Low Dk, ceramic CTE control
AD255A	AD Series	2.55 ± 0.04	~0.0014	Yes (micro-dispersed)	Woven (unidirectional)	Lowest loss in AD family
AD260A	AD Series	2.60 ± 0.04	~0.0015	Yes (micro-dispersed)	Woven (unidirectional)	Telecom infrastructure
AD300A	AD Series	3.00 ± 0.04	~0.0022	Yes (micro-dispersed)	Woven (unidirectional)	Mid-Dk, cost-effective
AD320A	AD Series	3.20 ± 0.04	~0.0032	Yes (ceramic-filled)	Woven (unidirectional)	Compact RF, multilayer
AD350A	AD Series	3.50 ± 0.04	~0.0030	Yes (ceramic-filled)	Woven (unidirectional)	Higher Dk stripline
AD1000	AD Series	10.2 ± 0.25	~0.0023	Yes (heavily loaded)	Woven glass	Circuit miniaturization
DiClad 880	DiClad Series	2.17 / 2.20	0.0009	No	Woven (unidirectional)	Ultra-low Dk and loss
DiClad 870	DiClad Series	2.33	0.0013	No	Woven (unidirectional)	Medium-low Dk
DiClad 527	DiClad Series	2.40–2.65	0.0018	No	Woven (unidirectional)	Mechanical stability
DiClad 522	DiClad Series	2.40–2.65	0.0018	No	Woven (unidirectional)	Mechanical stability

The first thing that jumps out is the DiClad 880’s dissipation factor: 0.0009 at 10 GHz. That figure puts it in the same tier as Rogers RT/duroid 5880 — widely regarded as the benchmark for low-loss PTFE materials. The AD255A, the best-performing AD Series grade at comparable Dk, comes in at ~0.0014. Both are excellent, but if you’re designing a system where every tenth of a dB in insertion loss matters, the DiClad 880 has a genuine electrical edge.

The flip side: the AD Series ceramic loading gives it a significantly better Z-axis CTE and more stable Dk vs. temperature behavior — advantages that matter enormously in applications with wide temperature cycling or demanding PTH reliability requirements.

The Ceramic Filler Difference: Why It Changes Everything

This is the technical heart of the Arlon AD vs DiClad comparison, and it deserves a careful explanation rather than just bullet points.

H3: Z-Axis CTE and Plated Through-Hole Reliability

Pure PTFE laminates have a notoriously high Z-axis CTE. PTFE expands significantly in the through-thickness direction under thermal cycling, creating tensile stress on the copper barrel of plated through-holes. Over repeated thermal cycles — think reflow soldering, field temperature swings, or ATE burn-in cycles — this stress accumulates and eventually produces barrel cracks or PTH failures.

Ceramic loading in the AD Series directly suppresses this Z-axis expansion. The ceramic particles act as a physical constraint in the PTFE matrix, pulling the Z-axis CTE toward lower values and reducing the expansion mismatch between the laminate and the copper PTH. The result is meaningfully better PTH barrel fatigue life in the AD Series compared to unfilled DiClad grades at equivalent Dk and thickness. For multilayer boards with many through-holes crossing multiple dielectric layers, this difference shows up in reliability testing and field failure analysis.

DiClad 522 and DiClad 527 partially compensate for this with their higher fiberglass ratio — the fiberglass provides mechanical constraint in both X-Y and Z directions. But even these grades don’t match the PTH reliability profile of the ceramic-loaded AD Series, particularly in demanding thermal environments.

H3: Dk Stability Across Temperature

PTFE has a well-known molecular quirk: a second-order phase transition that occurs at approximately 19°C. At this temperature, PTFE’s crystalline structure rearranges slightly, causing a small but measurable step change in dielectric constant. For most applications this is negligible, but in phase-sensitive systems — phased array antennas, precision filters, coherent radar — it can cause measurable performance drift when the board temperature crosses that threshold.

Ceramic filler in the AD Series helps moderate this effect by providing a dielectric component whose properties don’t change at 19°C. The net result is a flatter Dk-vs-temperature curve across the operating range. DiClad materials, lacking this ceramic moderating element, show more pronounced Dk variation at the PTFE phase transition temperature. Arlon’s CLTE and CLTE-XT products take this concept furthest, with a specifically engineered formulation to minimize the phase transition effect — but even the standard ceramic-loaded AD grades outperform pure PTFE/glass DiClad grades on this metric.

Structural Differences: Ply Orientation and Isotropy

One structural detail that rarely gets the attention it deserves: ply orientation. In DiClad laminates, the fiberglass plies are aligned in the same direction — what the datasheet describes as “unidirectional” construction. Cross-plied versions of many of these materials are available as Arlon CuClad materials.

This is not a minor detail for antenna designers. Unidirectional construction means the material has slightly different electrical and mechanical behavior in the warp direction vs. the fill direction of the fabric. For simple two-layer boards this is rarely a problem. But for wideband array antennas, precision couplers, and components where in-plane isotropy matters for pattern and phase uniformity, the cross-plied CuClad versions (or materials with random-fiber reinforcement) may be preferable.

The AD Series uses heavier woven glass styles with higher glass-to-PTFE ratio, which tends to average out some of the anisotropy simply through the material’s composition — but it’s still not a cross-plied construction. Engineers designing phased array elements where identical E-plane and H-plane behavior is critical should consider this factor when evaluating both families.

Dk Range and Application Targeting

The AD Series spans a dramatically broader Dk range than the DiClad Series, and this is one of the most practical differentiators between them.

Dk Range	AD Series Coverage	DiClad Series Coverage	Typical Application
2.17–2.33	AD250A (2.50 min) — not available	DiClad 880, DiClad 870	Lowest-loss transmission lines, mmWave
2.40–2.65	AD250A, AD255A, AD260A	DiClad 522, DiClad 527	Base station antennas, LNAs, filters
2.65–3.50	AD300A, AD320A, AD350A	Not covered	Power dividers, radar feeds, 5G sub-6
3.50–10.2	AD450, AD600, AD1000	Not covered	Miniaturization, high-Dk applications

This comparison makes the niche structure clear. DiClad excels in the very-low-Dk tier — specifically the 2.17 to 2.65 range where achieving the lowest possible loss tangent is the primary objective. AD Series covers the full working range from 2.5 up to 10.2, with ceramic loading enabling the higher Dk values and improved CTE that DiClad’s pure PTFE/glass construction cannot achieve.

If your design target is a Dk below 2.5 with the absolute minimum loss — for applications like mmWave low-noise amplifiers, precision phase shifters, or satellite payload filters — DiClad 880 is the natural starting point. If your design requires Dk values above 2.65, or if thermal and mechanical reliability requirements are stringent (high PTH count, wide temperature cycling, outdoor deployment), the AD Series is where you should look.

Fabrication Comparison: Similarities and Critical Differences

Both families share the same basic PTFE processing requirements. Neither is FR-4 compatible. Both require surface activation — either sodium naphthalene etch or plasma treatment — before electroless copper deposition. Both require vacuum lamination, controlled press cycles, and careful handling to avoid surface damage to the PTFE substrate.

The table below captures the practical process differences that affect fabrication planning.

Process Step	AD Series	DiClad Series	Notes
Surface Activation	Sodium etch or plasma	Sodium etch or plasma	Both required; no shortcuts
Lamination Pressure	300–1000+ PSI	300–800 PSI	AD ceramic grades may need higher pressure
Drilling	Ceramic loading increases bit wear	Slightly lower bit wear	AD grades with heavy ceramic loading reduce bit life
Dimensional Stability	Better (ceramic + heavy glass)	Variable (lower in high-PTFE grades)	DiClad 880 softer and less stable than DiClad 527
Z-axis CTE	Lower (ceramic controlled)	Higher (especially DiClad 880)	Significant PTH reliability impact
Panel Handling	Standard PTFE care	Extra care for high-PTFE DiClad 880	DiClad 880 is soft and conformable
Lead-Free Compatibility	Yes	Yes	Both survive lead-free reflow temperatures
Inner Layer Adhesion	Standard PTFE activation	Standard PTFE activation	Both follow same process

One practical note on drilling: the ceramic particles in AD Series laminates act as a mild abrasive against drill bits. This accelerates drill bit wear compared to non-ceramic DiClad grades. For high-volume production, factor in higher tooling costs when running AD Series ceramic grades, particularly AD320A and AD350A. DiClad 880 presents the opposite challenge — its soft, high-PTFE composition tends to be more prone to burring and fibre pull-out during drilling, and requires a high chip load and appropriate entry and backup materials.

Application Decision Guide: AD Series vs DiClad

Design Scenario	Recommended Family	Specific Grade	Reason
Lowest insertion loss, Dk ~2.17–2.20	DiClad	DiClad 880	Unmatched Df = 0.0009
Low insertion loss, Dk ~2.33	DiClad	DiClad 870	Best loss/stability balance
High mechanical stability, Dk ~2.40–2.65	DiClad or AD	DiClad 527 or AD255A	DiClad 527 for stability; AD255A for PTH reliability
Base station antenna, cost-sensitive, 1–6 GHz	AD	AD255A, AD260A	Ceramic CTE + good loss + cost-effective
5G sub-6 GHz, multilayer	AD	AD320A	Ceramic stability, controlled Dk for buried layers
High-Dk filter/coupler miniaturization	AD	AD1000	No DiClad equivalent in this Dk range
Wideband radar feed network, phase-critical	DiClad or CLTE	DiClad 870/880 or CLTE	DiClad for loss; CLTE for Dk stability
Multilayer PTFE build, >4 layers	AD	AD Series with bondply	Better PTH reliability for complex builds
Military radar, temperature cycling	AD	AD320A or CLTE	Ceramic CTE control, better thermal stability
Satellite payload, sub-12 GHz	DiClad	DiClad 880	Maximum gain in constrained loss budgets

Useful Resources for Engineers

Resource	Description	Access
Arlon DiClad Series Datasheet	Official Dk, Df, and mechanical properties for all DiClad grades	rogerscorp.com (Arlon/DiClad page)
Arlon AD Series Datasheet	Full specifications for AD250A through AD1000	arlonemd.com, rogerscorp.com
Arlon DiClad/CuClad/AD Fabrication Guide	Shared fabrication guidelines document covering all three families	rfglobalnet.com (PDF)
Rogers DiClad Series Page	Interactive specifications and material selector	rogerscorp.com/diclad-series
Arlon Microwave & RF Materials Guide	Full portfolio overview including all PTFE families	integratedtest.com (PDF)
IPC-4103	Industry specification for PTFE-based high-frequency laminates	ipc.org
IPC-TM-650	Test methods for Dk, Df, and other laminate properties	ipc.org
Arlon PCB Design and Fabrication Guide	Practical material selection and stackup guidance	pcbsync.com/arlon-pcb

5 FAQs: Arlon AD Series vs DiClad Series

FAQ 1: Is DiClad 880 the same as Rogers RT/duroid 5880?

They are not the same material, but they target the same performance tier and are often specified interchangeably for applications needing a Dk of approximately 2.17–2.20 with ultralow loss. DiClad 880 uses woven fiberglass reinforcement, while RT/duroid 5880 uses randomly distributed glass microfibers. The woven fiberglass in DiClad 880 provides better X-Y dimensional stability than RT/duroid 5880, making it easier to achieve tight registration on inner layers. However, RT/duroid 5880’s random microfiber construction provides more uniform electrical properties in all directions of the XY plane — an advantage for circular polarization antenna elements or components where in-plane Dk isotropy is critical. Both share a dissipation factor of 0.0009 at 10 GHz. For most commercial and defense filter, combiner, and LNA applications, DiClad 880 is a direct functional equivalent with a dimensional stability advantage.

FAQ 2: Can I replace an AD Series grade with a DiClad grade at the same Dk value?

Not without careful evaluation, even if the Dk values overlap (for example, AD250A at 2.50 vs. DiClad 527 at 2.40–2.65). The ceramic filler in AD Series grades gives them a lower Z-axis CTE than the DiClad equivalent. If you substitute DiClad 527 for AD255A in a multilayer design with a high PTH count and wide operating temperature range, you should run a PTH reliability analysis before committing — particularly if the board will see lead-free assembly cycles followed by field thermal cycling. Electrically, the substitution may be straightforward for simple two-layer boards. For multilayer builds or high-reliability applications, the CTE difference is a genuine risk that shouldn’t be assumed away without analysis.

FAQ 3: Why does the AD Series have a ceramic filler but DiClad does not?

The two families were engineered with different primary objectives. DiClad was designed to push the lower boundary of achievable Dk and dissipation factor using the simplest possible PTFE/glass formulation — the pure system without ceramic maximizes the PTFE contribution to the dielectric, delivering the lowest possible loss. The AD Series was designed to serve a broader Dk range while also improving the practical manufacturing characteristics — particularly dimensional stability, PTH reliability, and Dk range extension — that matter for higher-volume commercial production and more complex multilayer applications. The ceramic loading in AD Series is what enables it to cover Dk values up to 10.2 (in AD1000) that would be physically impossible to achieve by adjusting fiberglass content alone. It also enables tighter Dk production tolerance control through better compositional uniformity.

FAQ 4: Which series is better for filter and coupler design?

DiClad laminates are frequently used in filter, coupler, and low noise amplifier applications, where dielectric constant uniformity is critical. They are also used in power dividers and combiners where low loss is important. The DiClad Series has a historical design heritage in filter and coupler work precisely because its lower achievable Dk (particularly DiClad 880 at 2.17) reduces conductor loss on the resonator elements and coupling structures. At Dk 2.17, trace widths for a given impedance are wider than at Dk 3.0+, which reduces ohmic losses in narrow filter elements. For narrowband filters, couplers, and LNAs where insertion loss is the dominant specification, DiClad 870 or DiClad 880 is typically the first choice. For power dividers and combiners where thermal dissipation and reliability in high-power operation matter more, the better thermal conductivity and CTE stability of the AD Series (particularly AD300A or AD320A) can tip the balance.

FAQ 5: Where do I download the current datasheets for both families?

Following Rogers Corporation’s acquisition of Arlon, documentation for both families is hosted across the Rogers and Arlon website infrastructure. The DiClad Series product pages — including DiClad 527, DiClad 870, and DiClad 880 — are accessible at rogerscorp.com under Advanced Electronics Solutions → DiClad Series Laminates. Each product page links to the datasheet and also connects to Rogers’ Laminate Properties Tool, which allows interactive filtering by Dk, Df, and thickness. AD Series datasheets are available at arlonemd.com and also through the Rogers product documentation portal. The shared fabrication guidelines document covering DiClad, CuClad, IsoClad, and AD Series laminates is available as a PDF download through RF Globalnet’s documentation library. This is an essential document if you’re setting up a new process line for either family, as it covers surface activation, lamination parameters, drilling recommendations, and PTH processing in detail.

Making the Call: AD Series or DiClad for Your Next Board?

The cleanest way to frame the Arlon AD vs DiClad decision is this: DiClad is for when you need the lowest achievable Dk and loss in the 2.17–2.65 range and your design is relatively simple (low layer count, moderate PTH demands, controlled thermal environment). The AD Series is for when you need the broader Dk range that ceramic loading enables, or when PTH reliability, CTE stability, and Dk-vs-temperature performance are genuine design constraints.

Most of the board designs that engineers encounter in 5G infrastructure, automotive radar, and defense electronics fall into the AD Series zone — multilayer, thermally demanding, with many through-holes and assembly cycles that stress the board mechanically. The DiClad Series finds its natural home in the highest-performance two-layer RF work: satellite payload boards, high-Q filters, precision microwave test hardware, and LNA substrates where the insertion loss budget is tight and the board construction is relatively simple.

Knowing which situation you’re actually in — and not defaulting to the most expensive option when a more moderate choice covers the requirements — is the kind of material judgment that separates an experienced RF engineer from someone who’s still learning what these datasheets actually mean in practice.

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For hands-on Arlon material selection support and fabrication guidance, the resources in the table above are the right starting points. Arlon’s applications engineering team at arlonemd.com can also assist with non-standard thickness requests and custom Dk requirements for AD Series grades.