A range of different materials can be used when manufacturing circuit boards. However, they are not all the same. Each material brings something different to the table in terms of performance, tolerances, durability, and more. An informed decision here will maximize performance and durability, reduce weight, and ensure that your design performs to expectations.

Board Types

Circuit boards come in a wide range of types and are classified by component location, stack-up, design, bendability, strength, and electrical functionality. Before choosing a material, make sure you know which classification your design falls into, as this will affect material choices and other decisions.

FR-4

FR-4 is a commonly used material in the design of circuit boards. It is actually made of fiberglass (technically a glass-reinforced epoxy laminate), which means it is relatively lightweight and affordable. For this reason, it is often used in lower-end consumer electronics. The letters FR indicate that this material is also flame retardant, which can be important in applications where heat dispersal is a consideration. It is also known for its high mechanical values, as well as its ability to insulate and perform well even in more humid conditions. However, it may not have the thickness, durability, or capacity for higher-end or higher-performance applications.

When to use it: use FR-4 material in products where cost is a consideration, but you want effective performance across a wide range of applications. Typically, you’ll find FR-4 used in substrate/laminate boards. We recommend it for standard circuit boards.

Rogers Material

The Rogers company also manufactures material for circuit boards. The company offers several options, but one they are best known for is PTFE (Teflon). Teflon costs more than FR-4, but it provides better performance for RF circuit boards because it has a lower signal loss rate. Other advantages include a wide range of dielectric constant values, improved management of heat, and better control over impedance. The trade-off is the higher cost, coupled with slightly more weight.

When to use it: use this material in applications where power management is important, as well as where RF, microwave, or high-performance functionality are necessary. Note that this is a good material for mobile use, too. Typically used in laminate boards, we recommend this option for high frequency, microwave, and high-power situations.

Metal

Metal is an option for the base of circuit boards. So-called “metal core” boards offer greater heft, but also provide better durability and strength. Most are made from aluminum, but alloys exist that can be used instead. Typically, these boards feature the metal base layer, a second layer of conductive dielectric material, and then the final layer of copper on the top. Metal core circuit boards are widely used in solid-state applications, and in use cases where ceramic substrates cannot be used.

When to use it: metal core circuit boards are well-suited for LED applications, but can also be used for other lighting applications, and they also play a role in automotive electronic design.

HDI

HDI, or high-density interconnector, is yet another option for circuit board design. The name says it all – this material offers a high line distribution density and is often used in situations where designers need to reduce weight and size without sacrificing electronic performance. HDI can make use of blind and buried vias, as well as microvias, vias in pad, and through vias from surface to surface.

When to use it: use HDI where density is a consideration, as well as when size and weight are serious concerns. Note that HDI also offers reduced heat transfer included stress.

High Tg

As the temperature of the circuit board and surrounding environment rises, the material of the board’s base layer actually shifts states. The higher the temperature at which the material can remain rigid, the better performing the material will be for board design. Of course, in low-temperature environments, this is not much of a concern. However, with high-temperature environments, the glass-transition temperature (Tg) is important. High Tg materials offer the temperature resistance required for these applications, and they are beginning to be more commonly used across industries.

When to use it: high Tg materials are all about heat control, so this material is well-suited for designs where stability at high temperatures is critically important. We recommend this material for high density needs.

A Note on Solder and Toxicity

Soldering circuit boards can expose you to lead-carrying fumes (lead is sometimes contained within solder). Since any circuit board will require soldering, always solder boards in a well-ventilated area, while wearing appropriate protective gear.

A Full Range of Capabilities for Circuit Boards

At Advanced Circuits, we offer an end-to-end service for your needs in designing and manufacturing circuit boards. From choosing the right material to determining the right number of layers to full PCB assembly, we offer fast turnarounds and affordable pricing. No order is too large or too small. All circuit boards are manufactured within one of our US-based locations, which allows us to manufacture circuit boards for virtually alllayout projects, including DOD contracts.

Layout and Design Help for Circuit Boards

We believe in giving our customers every advantage possible. We understand that designing circuit boards can be incredibly complex, time-consuming, and frustrating. To help ease that burden, we offer free access to PCB Artist — our intuitive, unrestricted PCB design software — to walk you through the entire design process. Create designs of up to 28 layers, import from Eagle, and access a library of over half a million parts all in one place.

What is a Via?

A via is simply a hole, drilled or plated, that is in the PCB that will allow a signal to pass to the inner layer of the board or to the other side of the board. Vias often connect component leads to planes or signal traces. These allow a change to the signal layers. If the via goes completely through the PCB board, it is often called a through-via. You might also hear people refer to this as a through-hole.

Blind and buried vias are only available on boards that have at least four layers. They connect the inner layers with other inner layers that are adjacent to them or to adjacent surface layers.

A Closer Look at Blind Vias

When examining blind and buried vias, there are several different types of blind vias to be considered. There are photo-defined blind vias, controlled-depth blind vias, sequential-lamination blind vias, and laser-drilled blind vias.

• Photo-defined blind vias. The creation of photo-defined blind vias requires laminating a photosensitive resin to a core. The photosensitive sheet will have a pattern on it that indicates the areas where the holes will be made. It is then exposed to light that causes the remaining material on the board to harden. The PCB is then put into an etching solution that removes the material from the holes that were created, which creates pathways. Copper is then plated in the hole and on the outer surface, which creates the outer layer of the PCB.
• Controlled-depth blind vias. The creation of controlled-depth blind vias is very similar to creating through-hole vias. The only difference is that the drill used to make the holes is set so that it will only go partially through the PCB. Modern technology makes it possible to do this accurately so that the features below the hold will not come into contact with the drill. Once the hole is drilled, it will then be plated in copper. This is the least expensive option, but it does require that the holes are large enough that they can be made with a drill. While this will work for many PCB needs, it might not always be the right solution for everyone.
• Sequential-lamination blind vias. Sequential-lamination blind vias are created using a piece of laminate that is extremely thin. The process is similar to creating a two-sided PCB, where the laminate will be drilled, plated, then etched. This method creates elements in the side that will form the second layer of the board. On the other side will be a copper sheet, which forms the first layer. This assembly is then laminated with the other layers of the board before going through the remaining steps to becoming a complete PCB. This method is not used as much today as it was in the past, because it is expensive.
• Laser-drilled blind vias. Laser-drilled blind vias are made after the PCB has been laminated, but before the outer layer undergoes etching and lamination. There are different types of lasers used to make the holes today, but the results are the same.

A Closer Look at Buried Vias

When a via goes between two inner layers of a PCB but does not touch the surface of either side, it is called a buried via. Buried vias create connections between the inner layers. As the name suggests, vias are literally “buried” within the PCB. The functionality of a buried via is similar to that of a blind via, as the goal is to make sure that the PCB has the full functionality that is required. Buried vias help free up space in other areas of the board. To create buried vias, the inner layers with the vias are created first, and then other layers are added to the outside to build up the board.

The Benefits of Blind and Buried Vias

Because PCBs have limited amounts of space, blind and buried vias can be a huge benefit. They allow you to keep the PCB small, which is essential when working with electronics. The use of vias frees up space on the surface of the board; that space can then be used for other functions. Vias are a relatively simple solution, but you will need to be aware that the addition of blind and buried vias will add to the cost of the board.

Because there are many factors that go into getting the right PCBs with the correct blind and buried vias, it is important to work with a quality manufacturer.

Choose the Right PCB Manufacturer for Blind and Buried Vias

Adding blind and buried vias to your PCBs is a delicate process that’s best left to professional manufacturers. This means finding the right manufacturer for the job becomes very important. Advanced Circuits has led the PCB field for more than a quarter of a century and provides a range of services and technologies that can help to make your life easier. We can provide simple designs or complex boards according to your needs.

There are many benefits to working with us. We offer round-the-clock support, and we provide fast turnaround times. We also have instant online quotes available to give you an idea of how much your project will cost, as well as a way to track your order. Give us a call today with any questions you may have regarding blind and buried vias.

Understand the Mil Grade PCB Specifications

Those who would like to create circuit boards that can meet military specifications will need to make it a point to familiarize themselves with the current specs and standards. They will also need to create a plan that will ensure they are met before they begin designing the circuit. It will help for the designers to be familiar with the performance criteria that will need to be met, and to have a quality assurance plan to ensure they are adhering to the standards each step along the way.

Users are also going to want to learn the testing requirement and then create a testing regimen that checks those requirements. They will need to make sure that the circuit design is perfect and then continue to test it to look for any errors or weaknesses that might need to be addressed. Once the design is as perfect as it can be, and it meets the mil grade PCB specifications, it is possible to connect with a manufacturer.

However, not just any manufacturer will do. Even though someone might have a great design for a PCB, they have to be sure the manufacturer has the skills and tools to execute properly. This means they should always choose to work with a company that has worked on military contracts and have the ability to realize the design.

The mil grade PCB specifications will need to be matched exactly for anyone who is trying to create a genuinely military-grade board. Failure to adhere to any of the specifications will result in the circuit board not being usable. Even though it might still be viable, it would not be considered usable by the military because it fails to meet the specs, wasting time and energy in the process.

Why Are Military Grade PCBs Held to a High Standard?

The military requires PCBs that will provide them with high reliability and durability even when they are being used under challenging conditions in extreme environments. By creating boards that have high-temperature laminates, high-quality aluminum, and the best components, it will help to ensure that they can stand up to use in harsh locations and in machines, equipment, and vehicles that might be in a war zone.

Whether it is radar, lighting systems, targeting systems, or another use entirely, the military requires the best because there are often no second chances. If a PCB were to fail in the field, it would mean the loss of a mission or even a loss of life. Strict adherence to the military grade PCB specifications is essential.

Even those who are creating circuits that will not be used in any military capacity will want to consider creating according to the mil grade PCB specifications. This will help to ensure better quality, highly reliable PCB. The cost of these boards will typically be somewhat higher depending on the exact specs that are used, but most will find that the added cost will be well worth it. Regardless of what type of circuit is being created, ensuring that it is the best quality possible is always a good idea.

Why Put Your Trust in a Third-Party PCB Manufacturer?

When choosing a company to manufacture PCBs that need to meet mil grade PCB specifications, it makes sense to work with a company that can produce printed circuit boards for the Department of Defense Contracts. Even if individuals are not creating PCBs that are for the military, knowing that they are working with a manufacturer that is trusted by the military can provide greater peace of mind.

Those interested should contact a trusted manufacturer in the field that provides state-of-the-art manufacturing capabilities to meet whatever design criteria is set forth. These high-quality options can provide buried chip resistors, stacked microvias, laser-drilled microvias, direct laser imaging, blind and buried vias, up to 40 layers, air pockets between the layers, heavy copper, multilayer RF designs, oversized boards, and more to meet specific needs.

They will also have new materials that can be used for a range of designs. These include halogen-free UL certified materials, high-speed/ultra-low DK, new RF products, Rogers 2929 bondply, 3M ECM, ROHACELL, and Zeta Lam SE.

It is important to choose a leader in producing PCBs for commercial use as well as for aerospace, the medical field, and other markets. Regardless of what it is you need for the PCB, users should be able to trust the manufacturer’s commitment to providing the best in quality, performance, and reliability in the industry.

Learn More About Mil Grade PCBs and Other Services

Those interested in having their PCBs manufactured through a manufacturer can learn more about what the company offers and then get in touch. In addition to the fast turnaround time, they should provide reliable manufacturing and assembly of the PCBs that are needed. All of the orders received will have a free engineering file review before they head to fabrication. This helps to ensure that buyers are not wasting your time and money with a circuit that does not work properly.

A good company has around the clock tech support for those who may have questions that can’t wait to get answered. It is also helpful if they don’t require a minimum amount when placing a PCB order. This allows customers to only have to buy what they need so they do not need to worry about having a hundred extra PCBs lying around.

Manufacturers may provide a free Gerber file viewer online, can give an instant quote, and can work with customers to create exactly what is needed. The sooner an interested buyer gets in touch, the sooner they can have your PCBs in hand thanks to fast manufacturing and shipping processes.

The benefits of heavy copper in PCBs include:

• Reduction of thermal strain
• Better current conductivity
• Can survive repeated thermal cycling
• Smaller PCB size due to layering of copper
• Increased connector site strength

Industries that benefit from heavy copper printed circuit boards are military/defense, automotive, solar panel and welding equipment manufacturers, and other sectors that require boards that can handle the heat generated by today’s complex electronics. Another prime industry where heavy copper makes sense is in industrial controls. Heavy copper plated vias are best at transferring heat to an external heat sink. Efficient power distribution is important to ensure high reliability of the PCB and heavy copper allows this to occur.

Heavy copper is not a new innovation, as it has been used for a long time in PCBs that can withstand the exacting requirements of military and defense applications, such as in weapons controls. Mainstream electronics makers increasingly require ways to transfer heat away from components, and heavy copper is becoming more prevalent in an growing number of non-military uses.

Heavy copper boards are fabricated using plating and etching techniques. The goal is to add copper thickness to via sidewalls and plated holes. Plated holes can weaken if a board is subjected to multiple cycles while in production, and the addition of heavy copper can strengthen these holes. Boards structured with heavy copper will allow for high current/power and control circuits on one board.

PCB manufacturers will check with customers and find out what their requirements are, and match the heavy copper fabrication process to specific needs. It will be important to know for example, the component type, layer count, and material requirements. The PCB manufacturer can quote the customer and present the pros and cons of using heavy copper. Advances in technology have created a process that utilizes both plating and edging.

Advanced Circuits offers heavy copper capabilities, all the way up to what is sometimes defined as Extreme Copper (up to 20 oz.). Discover more about our advanced manufacturing capabilities to meet your unique product demands and design criteria.

About Advanced Circuits

Since 1989, Advanced Circuits has been the leading printed circuit board quick turn manufacturer, specializing in both small and production quantities. Advanced Circuits operates divisions in Aurora, Colorado, Tempe, Arizona, and Maple Grove, Minnesota and is MIL-PRF-31032, MIL-PRF-55110G, AS9100C, ISO 9001:2008 certified, IPC 6012 class 3/3A qualified, ITAR registered and DOD contracts ready.

Consumer electronics and professional devices have come a long way since the turn of the century in terms of both hardware capabilities and available features. With better battery life and faster processing, smartphones have quickly become a necessity for nearly everyone. As such, engineers are working on taking the next step in advancing technology by developing true waterproofing capabilities for devices outside of specialty cases that are currently available. While wristwatches and some wearables are able to be submerged to a certain depth and still work properly, phones, cameras and other items running on printed circuit boards traditionally are not.

Apple is researching hydrophobic conformal coatings and silicon seals to join connectors with the PCB and create a waterproof solution for future products. This technology can be a significant step forward for the industry but may also affect which components and materials can be used to achieve the desired functionality. In addition to phones, advanced methods of waterproofing will prove valuable for manufacturing, defense and other applications.

Staying on Top of Trends for Printed Circuit Boards

As you work on perfecting the design for your printed circuit boards consider the new technology available for components and laminates. You do not want to limit your application by trying to deeply cut costs and sacrifice quality. By staying on top of the latest PCB trends your team will be able to take advantage of new developments to take things to the next level. Learn more about what is going on in the PCB industry and how you can get the most value and performance from your circuit boards by contacting an expert at Advanced Circuits today.

Safe & Reliable Power Sources – The Role of PCB Boards

A lot of focus in recent years has been on developing long-lasting and environmentally friendly power sources for cars, trucks and other vehicles. This includes for electric bicycles and other battery-powered transportation that people rely on every day. In addition to improving safety and adding new features, designers continue to work on reducing the risk of battery failure. While it is a rare occurrence, rechargeable batteries on bicycles and electric carts can overheat and cause fires. Having a power source that is safe and reliable is necessary for all of the vehicle’s components to run properly. Spending time finding a battery and designing an efficient printed circuit board will allow your team to deliver the quality consumers expect.

How Printed Circuit Boards Affect Safety

In vehicles, a number of complex systems must all be able to communicate. If even one system is off, such as the deployment of airbags, there can be catastrophic consequences. Maximizing the capability of printed circuit boards not only ensures these systems work together; it also gives consumers peace of mind when choosing to purchase a new vehicle. As your team works to develop new products and features for vehicles, from electronic bikes to cars that can park themselves, consider ways to increase performance without sacrificing space or the quality of your PCB.

When it comes to electric devices and consumer electronics you are developing start with a PCB that is designed to fulfill the unique needs of the application. Learn more about circuit board design and place your next PCB order by contacting a representative at Advanced Circuits today.

Miniaturization is the name of the game for electronics companies these days. As new devices in all industries are announced, the race is on to create something even smaller and more powerful. However, does having smaller printed circuit boards in smaller packages actually benefit a company? As you and your team work on new concept designs for products, keep in mind these factors that will affect the quality and cost of your project.

• Materials – Organizations attempt to cut costs by shrinking the size of a component, hoping that smaller components lead to less material used and lower costs.
• R&D – While materials costs may go down in the short term, the research and development costs associated with creating these smaller components may outweigh the benefits initially.
• Process Development – In addition to the initial costs of creating the materials and miniaturizing PCBs, organizations also face costs associated with refining processes.

Weighing the Costs and Benefits of Smaller Printed Circuit Boards

In the long run, smaller printed circuit boards can lead to lower overall production costs. After initial investments in new components and PCB materials, engineers are able to work more performance and reliability into smaller packages. The key is to continually improve upon PCB designs to find new ways to maximize chip space. The result will be better quality, which is especially important when you are tasked with constantly adapting to new changes in technology. Get a jump on your next design and see how you can make the most out of your circuit boards with free PCB Artist software from Advanced Circuits.

For years, epoxy laminates and glass fiber have been the foundation of the printed circuit boards in use throughout the world. In essence, these materials make up the green board that houses the components, resistors and connections needed to run the entire operation. It is no surprise that the PCB market has the largest demand for these materials, which is leading to projected growth in the industry. As more and more product makers retool and improve home appliances and other devices, the performance limits of epoxy laminates and glass fiber will be tested. For the time being, these materials will continue to dominate due to their proven track record and the need for trusted PCBs for critical and delicate applications, such as those in the medical, defense and manufacturing industries.

Could New Laminates be on the Horizon for Printed Circuit Boards?

While epoxy laminates and glass fiber have been the top choice for printed circuit boards, the latest trends in technology could usher in new materials quickly. This is due to the fact that it is unknown how the current materials will perform under a variety of tests from newer devices. For example, new wearables and other devices that need to improve performance in smaller packages are springing up every day. As such, engineers and product designers are working to find solutions that meet the individual needs of each project.  CompositesWorld reported in October of 2014 that changes were in the works, with market research firm Lucintel predicting that glass fiber yarns could change from ‘200 or 400 filaments in a 7- or 9-micron diameter, giving way to 50-filament, 4-micron yarn.’ Lucintel mentioned that manufacturers could actually move away from glass fiber due to greater performance requirements in most markets. By examining the laminates that are available to you the next time you place a PCB order you will be able to get a sense for how your circuit boards will perform under various conditions. Learn more about your options and get started on your next PCB design by contacting an expert at Advanced Circuits today.

When you are designing printed circuit boards for your application, it is important to use materials that are going to give you the performance you need to make it a success. If you need something specifically for a high frequency, microwave or RF application, you will need to work with a manufacturer to get the laminates that will keep everything on track. These laminates often require different types of b-stage/prepreg or bonding sheets to laminate them for multilayer PCB designs. The most commonly used is the Rogers RO4000 series. Talk with an expert at Advanced Circuits to learn about the materials that are best for your PCBs.

Find out more about how to select the right PCB materials for high frequency applications by reading EDN Network’s article, Selecting PCB materials for high-frequency applications. It discusses price and performance trade-offs and other factors that need consideration, depending on your application.

Advanced Circuits Makes it Easy to Design PCBs

PCB Artist software, available for free from Advanced Circuits, now has the industry’s largest component library. This will help you design your PCBs with as much detail as you need in order to get the result that will be perfect. For more information on the free software, as well as information on how to submit your design to be manufactured, contact a representative at Advanced Circuits today.