# What Is IT180A PCB Material? Properties, Uses and Manufacturing Guide _Published: 2026-11-03_ Table of Contents Toggle - What Is IT180A PCB Material? - Why Is IT180A Used in Multilayer PCBs? - How Do Tg, Td and CTE Describe IT180A? - What Are the Detailed IT180A Material Parameters? - IT180A vs Standard FR4: What Is the Difference? - Why Do IT180A Datasheet Values Differ by Revision? - How Does IT180A Support Lead-Free Reflow? - How Does IT180A Affect Plated-Hole Reliability? - Is IT180A Suitable for Controlled Impedance? - Is IT180A a Low-Loss Material? - How Should IT180A Cores and Prepregs Be Specified? - Which PCB Applications Use IT180A? - How Do We Manufacture IT180A Multilayer PCBs? - IT180A FAQs - What Should You Include in an IT180A PCB RFQ? [IT180A](https://www.bestpcbs.com/blog/2026/11/it180a-pcb-material/) is the common search form of ITEQ’s IT-180A, a halogen-free, high-Tg FR-4 laminate system developed for multilayer PCBs that need lower Z-axis expansion than conventional FR-4. Its value is not just a higher glass-transition temperature. Designers choose it when plated-hole reliability, lead-free assembly exposure, dimensional stability and a manufacturable multilayer stackup must be considered together. The exact laminate or prepreg designation and datasheet revision still matter, so a material callout should identify more than the words “high Tg.” ![IT180A PCB material used in a realistic high-density multilayer PCB](https://www.bestpcbs.com/blog/wp-content/uploads/2026/11/it180a-pcb-material-hero.jpg) ## What Is IT180A PCB Material? IT180A is a high-Tg, filled epoxy FR-4 laminate and prepreg family. The official material name normally appears as **IT-180A**; the unhyphenated **IT180A PCB material** is the same search term, not a different grade. It uses woven glass reinforcement and a phenolic-cured resin system. Copper-clad cores and matching prepregs can be combined in a multilayer construction, subject to the available glass styles, resin contents, copper foils and dielectric thicknesses. At EBest Circuit (Best Technology), we use the approved material designation in the stackup and purchasing record. We do not treat every high-Tg FR-4 as an automatic substitute because resin behavior, dielectric data, available constructions and customer approvals may differ. ## Why Is IT180A Used in Multilayer PCBs? IT180A is used when a multilayer board needs stronger thermal robustness than a basic FR-4 construction. A higher Tg keeps the resin in its glassy state over a wider temperature range, while lower Z-axis expansion reduces the amount of thickness-direction movement applied to plated through holes during heating. Those two properties support reliability, but neither one alone proves that a finished board will survive its assembly profile or field environment. For a [multilayer PCB](https://www.bestpcbs.com/products/multi-layer-pcb.htm), the complete result also depends on layer count, finished thickness, hole diameter, copper balance, resin fill, lamination quality, drill condition and copper plating. Material selection and fabrication design therefore need to be reviewed as one stackup. ## How Do Tg, Td and CTE Describe IT180A? Tg, Td and CTE answer different questions. Tg marks the glass transition of the cured resin. Td is a decomposition-temperature measurement based on mass loss. CTE describes how quickly the material expands with temperature, and its value changes above Tg. A board does not become unusable the moment it reaches Tg, and a high Td does not mean the laminate can operate continuously near that temperature. ![Difference between IT180A Tg, Td and Z-axis CTE](https://www.bestpcbs.com/blog/wp-content/uploads/2026/11/it180a-thermal-parameters.jpg) This distinction prevents a common specification error: using one headline temperature as a replacement for the entire thermal profile. Reflow peak temperature, time above liquidus, repeated cycles, board moisture and the operating environment must be evaluated separately. ## What Are the Detailed IT180A Material Parameters? The following values are representative of the referenced multi-page IT-180A datasheet. They must remain attached to the stated method, frequency and material construction. Values can change with resin content, specimen thickness and datasheet revision. Parameter Representative IT-180A value Method or condition How to use it Tg 175°C typical; 170°C minimum DSC Compare resin transition behavior using the same test method. Td 345°C typical; 340°C minimum TGA, 5% weight loss Do not use as a continuous operating-temperature rating. Z-axis CTE below Tg 45 ppm/°C typical TMA, alpha 1 region Supports plated-hole strain analysis below Tg. Z-axis CTE above Tg 210 ppm/°C typical TMA, alpha 2 region Shows why time above Tg matters during thermal exposure. Z-axis expansion Approximately 2.7% 50–260°C Use with board thickness and PTH geometry, not as a stand-alone pass/fail limit. Dk Approximately 4.4 at 1 GHz Representative datasheet construction Confirm the actual construction and frequency before impedance modeling. Df Approximately 0.015 at 1 GHz Representative datasheet construction Shows that high Tg does not automatically mean low loss. Flammability UL 94 V-0 Listed construction and thickness range Verify the applicable UL construction instead of copying the label alone. Older and newer IT180A datasheets may show different typical values or test presentations. The approved fabrication package should therefore retain the supplier, exact grade and revision used for the design decision. ## IT180A vs Standard FR4: What Is the Difference? IT180A is still an FR-4 material, but it is formulated for higher Tg and lower Z-axis expansion than many conventional FR-4 grades. The practical comparison is not “FR-4 or IT180A”; it is IT180A versus the exact alternative grade and construction being considered. ![IT180A versus standard FR4 under thermal cycling around a plated through hole](https://www.bestpcbs.com/blog/wp-content/uploads/2026/11/it180a-vs-standard-fr4.jpg) Selection point Conventional FR-4 IT180A high-Tg FR-4 What still needs confirmation Glass transition Usually lower, depending on the grade DSC Tg around 175°C in the referenced sheet Use the same Tg test method for comparison. Z-axis expansion May be higher during assembly heating Designed for lower Z-axis expansion Check the actual alternative-grade datasheet. Lead-free assembly Depends strongly on grade and board design Intended for lead-free multilayer applications Validate moisture control and the real reflow profile. Signal loss Varies by resin system and construction Not automatically a low-loss laminate Compare Dk/Df at the design frequency. Fabrication Common process knowledge is widely available Requires approved constructions and material control Confirm availability, stackup and process window. ## Why Do IT180A Datasheet Values Differ by Revision? Datasheet values differ because suppliers revise products, test methods, presentation formats and representative constructions. For example, an older sheet may present a rounded Tg or Td that is not identical to a later multi-page sheet. Dk and Df can also vary with resin content, glass style, thickness and frequency. Do not build a specification by selecting the best value from several documents. Record the exact source revision and keep each number with its method and condition. If an engineering drawing calls out a minimum property, it should state the method used to verify that property. ## How Does IT180A Support Lead-Free Reflow? IT180A supports lead-free assembly by combining high Tg, suitable decomposition resistance and controlled Z-axis expansion. The laminate datasheet includes time-to-delamination indicators such as T260 and T288, but those values are material tests, not a guarantee for every completed PCB. A finished board adds drilled holes, copper plating, solder mask, absorbed moisture and local copper-density differences. Before assembly, define storage and baking controls where needed, and review the actual number of reflow or rework cycles. A short assembly peak is not the same as continuous operating temperature. ## How Does IT180A Affect Plated-Hole Reliability? Lower Z-axis expansion can reduce strain on a plated through-hole barrel during thermal cycling. It does not remove the need for correct hole design and plating. Finished board thickness, drilled diameter, aspect ratio, copper thickness, drill smear removal and annular-ring geometry still control the stress concentration and current path. We review the smallest finished hole against the stack thickness before confirming a build. Our listed rigid-PCB capability includes a normal minimum hole of 0.20 mm, a 0.10 mm HDI minimum hole and an 8:1 aspect ratio, but these limits are not automatically combinable with every IT180A stackup. The actual panel size, layer count, copper weights and reliability requirements must pass DFM together. ## Is IT180A Suitable for Controlled Impedance? Yes, IT180A can be used for controlled-impedance routing, provided the calculation uses the actual core and prepreg constructions. A single generic Dk value is not enough. The field solver needs finished copper thickness, trace width, spacing, solder mask condition, dielectric thickness and a Dk appropriate to the material construction and frequency. For an [HDI PCB](https://www.bestpcbs.com/products/HDI-board.htm), laser-via build-up and thin dielectrics add more construction variables. Send the target impedance, layer assignment and stack constraints with the Gerber or ODB++ data so that the proposed stack can be checked before production. ## Is IT180A a Low-Loss Material? No. IT180A is primarily a high-Tg, low-CTE FR-4 material, not a dedicated ultra-low-loss laminate. The referenced sheet gives a representative Df around 0.015 at 1 GHz. That may be acceptable for many digital and industrial boards, but high-speed channels should be evaluated by insertion-loss budget, route length, frequency content, copper roughness and the exact construction. If loss is the limiting requirement rather than plated-hole thermal robustness, compare IT180A with an appropriate low-loss family. Do not select a material only because its Tg is higher. ## How Should IT180A Cores and Prepregs Be Specified? Specify the manufacturer, exact grade, core thickness, copper weight on each face and the required prepreg construction. “IT180A prepreg thickness” is not one universal number. Pressed thickness depends on glass style, resin content, copper distribution, flow and the surrounding stack. Specification item What to provide Why it matters Material identity ITEQ IT-180A or an explicitly approved alternate Prevents an unreviewed high-Tg substitution. Core construction Dielectric thickness and copper weight on both faces Controls impedance, overall thickness and etch feasibility. Prepreg Glass style or target pressed dielectric with resin requirement Supports resin fill and dielectric control. Finished board Overall thickness, tolerance, hole sizes and copper requirements Connects material selection to fabrication acceptance. Electrical targets Impedance values, layers, tolerances and test method Allows a construction-specific field-solver review. ## Which PCB Applications Use IT180A? IT180A is used in multilayer boards for automotive electronics, servers, networking equipment, telecom systems, data storage, industrial controls and heavy-copper designs. These applications do not use the material for one identical reason. A server backplane may prioritize layer count and plated-hole durability, while an automotive controller may emphasize repeated thermal exposure and dimensional stability. ![High-Tg multilayer PCB formats for networking automotive and industrial electronics](https://www.bestpcbs.com/blog/wp-content/uploads/2026/11/it180a-applications.jpg) The material is also relevant where lead-free assembly and multiple thermal cycles make a basic laminate marginal. Application names alone do not define the stack. The board-level requirements must still be translated into layer count, copper, hole geometry, impedance, thermal profile and acceptance criteria. ## How Do We Manufacture IT180A Multilayer PCBs? We begin with material and stackup review, then check inner-layer geometry, copper balance, prepreg resin demand, drill aspect ratio, lamination thickness and controlled-impedance requirements. Material identity is retained through purchasing and production records. Lamination, drilling, desmear and plating controls are matched to the approved construction rather than inferred from the words “high Tg.” EBest Circuit’s listed rigid-board capability extends to 32 layers, with normal 4/4 mil line and space and HDI capability down to 2/2 mil under suitable designs. These are capability boundaries, not a promise that the most aggressive line, hole, layer and thickness limits can all be combined in one board. We confirm the manufacturable combination after reviewing the data package. ## IT180A FAQs ### Is IT180A the same as IT-180A? Yes. IT-180A is the formal hyphenated material name; IT180A is the common search and shorthand form. ### Can IT180A replace any standard FR-4 material? No. Electrical properties, constructions, approvals, availability and process requirements must be compared before substitution. ### What is the IT180A prepreg thickness? There is no single thickness. Pressed thickness depends on glass style, resin content, copper distribution and the stackup. Use an approved construction proposal. ### Does a 175°C Tg mean a PCB can operate continuously at 175°C? No. Tg is a resin transition measurement, not a continuous-use temperature rating. Use the applicable material listing and the finished assembly’s environmental requirements. ## What Should You Include in an IT180A PCB RFQ? To prepare an accurate quotation, we need the Gerber or ODB++ data, drill files, fabrication drawing, stackup, finished thickness, copper weights, minimum holes, impedance targets, surface finish, quantity and assembly thermal requirements. Tell us whether IT-180A is mandatory or whether we may propose an alternate for approval. If the material revision or UL construction is controlled, include that requirement rather than relying on a generic “high-Tg FR-4” note. For an [IT180A high-Tg PCB](https://www.bestpcbs.com/products/high-tg-board.htm) build review, send the complete files to [sales@bestpcbs.com](mailto:sales@bestpcbs.com). Our PCB team will review the [IT180A](https://www.bestpcbs.com/blog/2026/11/it180a-pcb-material/) material callout and stackup before confirming the construction.