Frequently Asked Questions

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Please review Are RO4000 Materials Compatible with Lead Free Process for more information.

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Yes, this is very common and there is very little concern.  It is best to have a balanced construction of RO4000 and FR-4.  The only problem is typically a flatness issue, due to a mismatch of CTE between the RO4000 and FR-4 materials.  Rogers has a paper written to address this concern.  Another concern, which is seldom encountered, is bonding our RO4450 prepreg to a FR-4 substrate.  Most FR-4 substrates use a RTF (Reverse Treated Foil), which means that the Copper bonded to the FR-4 is the smooth side.  A plasma cycle is recommended to roughen the exposed FR4 surface.

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Not exactly, however if fabricators have the equipment and processes to process FR-4 successfully, then they should be able to process RO4000 materials successfully with some changes to processing parameters.

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Actually no. Standard PCB processing should be done with the layers that will be bonded to the PTFE substrate, as well as the PTFE substrate. The only concern is to not allow the exposed PTFE substrate (after selective etching the circuit image) to be altered. So, after etching, the exposed PTFE substrate should not be physically or mechanically altered by scrubbing or handling in general. A surface activation of the PTFE substrate is not necessary. Please refer to our fabrication guidelines for more information.

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Typically this is not required however, it is a safe practice. A bake at 250°F for 1 hour should be sufficient to remove any surface moisture.

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Typically lamination, drilling, scaling (dimensional stability) and plating.  Usually, lamination will be the most complex area, not that it is difficult, however it is different than most of prepreg lamination conditions.  Drilling a material with ceramic particles has many different considerations than most standard other materials will not even be thought of. With more layer counts, the alignment between these layers has more variables and scaling (dimensional Stability) becomes much more important.  Plating is seldom a problem by itself; it is typically a problem that is due to a previous process. Our fabrication guidelines address all of these.

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The primary thing to keep in mind is that TMM material is brittle and a very high modulus (stiff). It is not recommended to punch or shear the TMM material. Instead, drilling, routing and machining should be done. It must be expected that the drill life too will be dramatically shorter than more standard materials. Bending and handling should also be avoided during fabrication as much as possible. The thinner grades of TMM laminates (<20mil) are more susceptible to cracking and fracturing due to mishandling.

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There are many considerations for fabricating a PCB using PTFE. It also depends on what type of PTFE material is used. The more “pure” PTFE materials, such as RT/duroid® 5870 /5880, have more issues for processing than do the loaded PTFE substrate such as the RO3000 and RT/duroid® 6000 materials. The ceramic loading of the RO3000 and RT/duroid 6000 materials helps with issues regarding CTE and dimensional stability. It also helps with an easier process to make the drilled through hole wall plateable. In the case of the RT/duroid 5000 materials, a chemical activation of the hole wall is necessary. The RO3000 and RT/duroid 6000 materials can use a plasma process, which is safer for fabrication and reliability. In general, the most critical issues for processing PTFE are drilling, possibility of entrapped chemistry, dimensional stability and CTE.

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Ramp rate (rate of rise) during lamination is very important.  A slow ramp rate (<4F/min) is desired.  More pressure is always better (>400psi).  A rough surface to bond to is mandatory.  Vacuum prior to lamination is not recommended.

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Most PCB bonding material will adhere to the PTFE substrates. The determinant is whether the bonding layer is a concern for good electrical performance. If the bonding layer is not electrically important then standard FR4 prepregs can be used. If it is electrically important, then the RO4450 prepregs can be used. If even better electrical performance is needed, then 3001 Bonding Film or FEP could be used.

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Most standard PCB bonding materials will adhere to the TMM® materials. The determinant is whether the bonding layer is a concern for good electrical performance. If the bonding layer is not critical for electrical performance then most standard PCB bonding materials can be used. If the bonding layer is important for electrical performance, then the RO4450™ prepregs can be used. If a better electrical performance is needed then the 3001Bonding Film or FEP can be used. However, bonding material options will not match the DK of the TMM.

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Rogers uses two different methods to measure dielectric constant.  The first, the clamped stripline test, follows IPC TM-650 2.5.5.5 and is used for internal process control only.  Because air is entrapped between the resonator and the material being tested, the resulting DK is lower than the value that should be used in the design process.  The second test, the full sheet resonance test, follows IPC TM-650 2.5.5.6, and is closer to the DK value that should be used during the design process.  Rogers has a short presentation, which explains the different test methods.

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This depends on many things. A thicker RO4000 printed circuit boards will have less tool life since there is more material abrading the drill tool. Also if other materials are used with the RO4000 materials, sometimes there will be smear issues at the interface of these other materials and the RO4000 materials which impact drill life. In general, if it is a simple, moderate thickness, pure RO4000 PCB, one thousand hits is a typical drill life.

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Rogers has a report that details this and should be referred to for more information. In general, the thinner the material is, the more the dimensional movement during fabrication. The 4 mil and 6.6 mil core materials will be the worst-case scenarios.

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There are many things to consider and Rogers has an article to assist. In general, the circuit material should be non-glass woven, use thinner copper that does not have copper plating in the bend area, does not have Nickel plating in the bend area, thinner circuit materials are used and the bend radius is well controlled. As a rule of thumb the minimum bend radius for a one time bend should be 10X the thickness of the circuit. If the bend is a dynamic application, then it should be 25X the thickness of the circuit.

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This is the most common defect regarding PCB fabrication of the RO3000 materials. The key issue is that the RO3000 materials have some porosity and can absorb processing chemistries. After the hole is drilled, there are wet processes used in which the chemistry can be absorbed into the drilled hole wall. If a bake is not done prior to copper plating of the hole wall, the chemistries will be sealed in. Later in a soldering process, the entrapped chemistries will volatilize and delaminate around the plated through holes.

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In order to achieve bonding of the copper foils and complete as much cross-linking as possible in dielectric materials, Rogers uses higher temperatures and pressures to produce laminates. These higher temperatures and pressures make the completed laminate more susceptible to pits and dents.

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There are several reasons why CTE is important. A material with a higher CTE (>100 ppm/°C) will have worse dimensional stability during the circuit fabrication process. Another issue is the reliability of the plated through hole. A high CTE will cause the material to expand more during soldering or other high temperature exposures and can fracture the plated through hole barrel. A material with high CTE could also have a shearing effect on components that have been soldered in place and then the board goes through some thermal cycling.

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Depending on our production schedule that may be possible. Please contact Customer Service for that request.

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Please contact Customer Service for that request.

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For High Frequency Materials, the following information is available:

• Product Data Sheets
• Properties - Detailed Characteristics
• Design Information
• Fabrication Guidelines
• Material Safety Data Sheets
• Technical Articles

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To download Rogers’ Advanced Circuit Materials Environmental documentation, please visit our MSDS Documentation. If you need additional information, please contact your Customer Service representative.

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You can receive samples by filling out the High Frequency material sample request form. If you are a professor or a student at a University and wish to design using Rogers’ materials, please use the University Program form.

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The first place to start is the Advanced Circuit Material Division’s product selector guide. Please review the High Frequency Laminates Product Selector Guide if you are interested in high frequency materials. If the configuration you are looking for does not appear available in this guide, please contact your customer service representative, as custom configurations are often available.

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We are always interested in finding out how we can better serve our customers. If you did not find what you were looking for on our website please send a note to our web master regarding the information you’re looking for. In most cases, we should be able to respond to you in 3-5 working days.

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We can certainly resolve that issue.  Just contact your Customer Service Representative.

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Please contact your Customer Service Representative to make changes on your order.

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For an order tracking number, please contact your Customer Service Representative.

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Lead times are different for the various products that we offer. Our Customer Service Department can answer questions on lead times.

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For a shipping date on a particular order, please contact your customer service representative.

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Our Customer Service department processes refunds on orders.

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Please contact your customer service agent for pricing and quote information.

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For information about placing an order and to insure you receive the right materials for your applications, please go to our Ordering Information page. If you need detailed stock availability and inventory information, contact your customer service representative.

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For high frequency Laminates, please go to the High Frequency Technical FAQ section, section of our website. If you still can’t find what you are looking for, please email your questions to our technical support team.

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Our Customer Service department can help you change your orders.

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Contact Customer Service to get documentation on your orders.