Available PCB Types
FS Technology, which is located in Shenzhen, China, is a PCBA processing company that specializes in turnkey PCB assembly. Along with our expertise in PCB assembly, we also offer comprehensive PCB manufacturing services to our customers. Our PCB manufacturing capabilities include up to 1-58L rigid board, 1-6L flex board, 2-10L rigid-flex board, and 1-6L aluminum/copper board (36/10). In addition to these PCB types, we also offer almost all other commonly used PCB types in the industry, and provide high-quality materials that meet industry standards and requirements. If you would like to learn more about the PCB types that we can provide and our detailed capabilities, please click on the link to visit the corresponding page.
Differentiation of PCB types
Hard and soft category of PCB
Printed circuit boards can be divided into flexible boards, rigid boards, and rigid-flex boards based on their different soft and hard processes. Each type of board has its unique properties, features, advantages, and disadvantages. In the following section, we will provide an overview of these three types of PCBs and explain their concepts to you.
Rigid PCB: Among the most common types
Rigid PCBs are perhaps the most commonly manufactured type of circuit board. They have a sturdy and inflexible structure that cannot be altered to different shapes or forms once the construction is complete. This type of circuit board has a straightforward design and is relatively easy to manufacture. There is no limit on the number of layers, and circuits with a single-layer, double-layer, or multi-layer can be easily constructed. The structure of a rigid PCB typically includes three parts: the substrate, the copper solder mask, and the top silkscreen. It is a very common type of circuit board, and the green motherboard found in our computers is a good example of a rigid board.
This simple and inexpensive type of circuit board can be found in almost every electronic product, such as X-ray machines, mobile phones, laptops, sensors, and communication equipment, among others.
Flexible PCB: foldable circuit type
This type of foldable circuit is known as a flexible circuit, flexible PCB, or FPC. It is typically composed of polyimide or polyester film with a polymer coating that protects the conductive circuit on its surface. Using this type of PCB in electronic projects offers the advantage of being able to modify and change it into different structures and shapes, thus reducing the size of the project and the number of components required, leading to cost savings. However, due to its flexible characteristics, it doesn’t offer higher reliability, so it is often used in combination with rigid boards to form a wider range of forms.
Flexible PCBs are commonly used in various industries, including consumer electronics PCB, radio frequency and microwave applications, and medical PCBs play a pivotal role in the medical industry.
Rigid-Flexible PCB: The Propeller of Microelectronics
The rigid-flex PCB is a more complex type of PCB that incorporates both the rigid and flexible PCB types mentioned earlier into a single platform. Electronics manufacturers create circuit boards with both flexible and rigid qualities depending on the requirements of the project. These boards consist of a flexible portion attached to a rigid material that helps to close the conductor layers and create a compact PCB. Although rigid-flex circuits are more costly, they eliminate the need for connectors and result in lighter and more contemporary circuit boards for electronic products.
This expensive PCB type is often utilized in high-tech equipment, such as high-precision military equipment, wearable medical electronic devices, and mmWave PCBA in 5G base stations.
PCB Types by Layer
Printed circuit boards can be manufactured with different numbers of layers depending on the requirements of the project and its structure. The layers can include single layer, double layer, and multi-layer options. While manufacturers strive to meet customer demands for the number of layers, they may be limited by their own manufacturing capacity and available materials. The following are the categories of PCBs based on the number of layers:
Single Layer PCB board: Circuits for low-end electronics
The single-sided or single-layer board is named so because the components of this simple circuit board are gathered on one side of the board, and its wires are gathered on the other side. It has only one layer of copper on the substrate material. Due to its cheap price and simple creation, this type of board is very commonly used in the electronics industry. As these boards come in a single layer, there is no intersection between the conductive layers, which means they require less space than multi-layered boards. Both SMD and THT packages can be used in these PCBs.
Advantages of single-sided PCB:
- It is the easiest to design and manufacture of all circuit boards;
- Due to its simple structure, it is extremely cost-effective for mass production;
- The testing process is simple and it is easy to modify after problems are identified.
Disadvantages of single-sided PCB
- The number of circuit board components that can be used is limited;
- The scope of application is small, and it is not suitable for complex applications.
Double-Layer PCB board: Simple circuit structure type
The board that has two copper layers on each side to make connections between components is called a double-sided or double-layered board. This kind of PCB has a conductive layer and a solder mask on each side of a single base layer. Electronic components are soldered on both sides of the PCB. Conductive holes are drilled and used to connect the two conductive layers.
Advantages of Double Sided PCB
- Reduces the size of PCB;
- Increases the density of PCB;
- Brings more flexibility in design;
- Allows for more efficient fabrication of complex designs;
- Cost-effective, aid in routing where there are more components and less space clearance.
Multilayer PCB board: The most complex type of circuit structure
If a PCB has more than two conductive layers, it is called a multilayer PCB. Due to the unique PCB manufacturing process of these boards, the number of layers is usually an even number. The structure of a multilayer PCB is like a sandwich, with multiple double-sided layers and insulation materials between them. All layers are interconnected with conductive holes, similar to a double-sided PCB. Higher layer counts allow electronic engineers to design more complex products, but also make their jobs more challenging.
Advantages of Multilayer Board Design
- Increase design flexibility
- Prerequisite for the production of smaller and more powerful electronic devices;
- Allows high-speed layouts that cannot be achieved with single- or double-layered boards.
Types of PCB substrate materials
FS Technology offers various types of materials for PCB creation, which are explained here. Almost all the types of materials used in PCBs can be ordered from us to use in your projects. We will help you select the required materials based on your project’s needs and design configuration.
FR-4 Fiberglass board (High TG, Halogen-free)
Traditional FR-4 PCB: Traditional FR-4 PCB: FR-4 stands for Flame Retardant number 4 and is made of woven glass reinforced epoxy resin. It provides strength and resistance to moisture, and is used in PCBs to provide insulation and separate copper layers to make connections, which enhances the strength of the boards.
High TG FR-4 PCB: High TG FR-4 PCB: High TG refers to the glass transition temperature, which is the temperature at which the substrate transitions from a rigid to a soft state. The TG value for conventional FR-4 PCBs is typically around 130 to 140 degrees Celsius, while medium TG values are around 150 to 160 degrees Celsius, and high TG values are above 170 degrees Celsius. High TG boards can absorb more heat and have better water resistance than normal FR-4 PCBs.
Halogen Free FR-4 PCB: Halogen-free FR-4 PCB: Halogen-free materials do not contain halogen elements, such as fluorine (F), chlorine (CL), bromine (Br), and iodine (I), which can release toxic substances when burned. Using halogen-free FR-4 PCBs can prevent the release of these substances in the event of a short circuit. In addition to being more secure, this type of circuit board also has the following advantages:
- Good heat resistance, withstanding temperatures up to 150 °C;
- Strong insulation performance, withstanding a breakdown voltage of 40KV;
- Excellent water absorption and moisture resistance, ensuring a longer lifespan.
PCB type of metal substrate material (Aluminum/Copper)
We often use the term “metal PCB” to refer to printed circuit boards with a metal substrate, typically made of either copper or aluminum. Let’s briefly introduce these two types of metal PCBs:
Aluminum-based PCBs: These boards consist of a thin conductive layer on an aluminum substrate. They are also referred to as aluminum clad or aluminum base PCBs. The structure of an aluminum PCB is similar to that of other types of PCBs, with a copper layer for soldering, a solder mask, and a silkscreen for component identification. Although this type of PCB is very common, it is typically constructed as a single or double layer, as manufacturing multilayer aluminum PCBs is complex and challenging. Aluminum PCBs are often used in applications that require efficient heat dissipation, such as LEDs.
Copper-based PCBs: These are the most expensive type of metal circuit boards, with the highest-quality heat dissipation. They are commonly used in high-frequency circuits, areas with large temperature differences, precision communication equipment, and the construction industry. Copper-based PCBs have a 4-layer structure, and their base material is referred to as a CCL. Their construction is similar to that of FR4 boards.
Polyimide: Comprehensive performance PCB type
The term polyimide, abbreviated as PI, is an organic high molecular polymer material composed of two parts: “poly” meaning polymer and “imide” meaning imide monomer, which are combined to create this material. It has excellent heat resistance, with a temperature range reaching above 400 °C and continuous high temperature resistance range of about 200-300 °C. The dielectric loss is only 0.004-0.007, making it belong to the F to H-level insulation category. The common types of polyimide include 2nd Generation, 3rd Generation, and Filled Polyimide.
Ceramic substrate: PCB type with thermal conductivity up to about 220 W/M. K
A ceramic PCB is a printed wiring board made with thermally conductive ceramic powder and organic binders, prepared at a temperature lower than 250°C, with a thermal conductivity of 9-20 W/m.k. During the manufacturing process of the ceramic substrate, a copper layer is attached to the alumina or SiC by applying high temperature. This board has superior heat transfer properties compared to other boards and excellent electrical features. Based on the constituent materials, this circuit board can be divided into three categories: alumina ceramic PCB, beryllium oxide ceramic PCB, and aluminum nitride ceramic PCB. Additionally, it can be divided based on the proportion of alumina, into 75%, 96%, and 99.5% alumina ceramic PCB.
Teflon: A kind of high frequency PCB material
The Teflon PCB is made of polytetrafluoroethylene or PTFE, a synthetic resin material known for its non-stick and non-reactive surface. This circuit board material can withstand high and low temperature environments and is often the first choice for high-frequency electronic applications due to its low dissipation factor and low thermal expansion coefficient. It can transmit signals at frequencies above 5 gigahertz, making it suitable for applications such as radio frequency circuits and mmWave PCBA.
PTFE, short for Polytetrafluoroethylene, is the material used in Teflon PCB construction, commonly used in high-speed electronics projects. For circuits that use RF and microwave signals, an FR4 material board can be expensive and may cause signal loss, making PTFE a better option. Although PTFE increases the dielectric constant value, it is still preferable over FR4.
Rogers PCBs are a special type of circuit board developed and manufactured by Rogers, primarily for high-speed and high-frequency applications. This board contains an epoxy resin core with metal clad copper and aluminum. Rogers PCBs have a constant temperature value, lower dielectric loss, and provide good dielectric strength to the board. They can be used with FR4 to achieve different dielectric constant values, ranging from about 2.55 to 10.2.
Taconic PCB: One of the microwave radio frequency circuits
This is a circuit board that uses Taconic (TLX-8, TLX-9) as the substrate material. These substances are a type of ceramic-filled PTFE. Taconic Corporation became a leading supplier to the food processing industry by pioneering the manufacture of PTFE-coated fabrics and other high-temperature/nonstick materials. Taconic PCB laminates can be milled, plated, and sheared using standard methods. Like other high-frequency materials such as Arlon and Rogers, Taconic laminates are microwave/RF PCB materials that are often used in telecommunication and aerospace projects.
Arlon: Premium high frequency board material type
Arlon (35N, 85N) is a PCB material used for making high-performance laminates and prepreg materials for various PCB-based projects. These materials offer better features such as thermal and mechanical strength compared to FR4. This substrate exists in different types such as woven glass and non-woven aramid. Common applications of Arlon include military instruments, heat sinks, and HDI in some communication projects.
Panasonic: One of the largest electrical brands in Japan
The Panasonic R-5575 is a multi-layered PCB structure made of high-speed, halogen-free material with low loss. This material is commonly used in radio antennas and in miniaturizing PCB boards. Other features of the Panasonic R-5575 include good thermal behavior, anti-aging properties, and water resistance. Its surface resistance value is 1 x 10^8 Ω.
CME 1: Materials for building a simple PCB
CME1 is a substrate material that is specifically used for the construction of industrial single-layer PCBs. The primary reason for using CME1 in single-layer boards is its cost-effectiveness, which makes it an ideal choice for cheaper and simpler PCBs. The construction of these materials is straightforward, and they have the ability to accommodate a large number of components, allowing for the assembly of many components on a single layer PCB.
CME 3: Cost-effective printed circuit board material
This material is used for two-layer boards that come in white color, and have a glass epoxy configuration. Although its mechanical strength is less than FR4, it is more cost-effective and can be a good alternative to FR4.
Types of PCBs differentiated by function
High frequency PCB: Types of circuits to solve signaling problems in electronics
High-frequency PCBs are high-end circuit boards used to facilitate the transmission of large amounts of data. The electronic products that use this type of circuit board have the following common features:
- Signal transmission speed greater than 12Gbps;
- Use of high frequency PCB type;
High frequency PCBs must have the following characteristics:
- The DK value should be small and stable. If the DK value is too high or fluctuates significantly due to changes in frequency, it may cause signal transmission delay;
- The DF value is crucial for this type of PCB as it affects the quality of signal transmission;
- The thermal expansion coefficient of high frequency PCBs should be the same as that of copper foil to prevent separation of the copper foil due to alternating hot and cold temperatures during operation;
- Low water absorption to prevent the DK and DF values from being affected in humid environments;
- Good resistance to heat, chemicals, impact, and peeling, similar to other types of PCBs.
Materials that can be used to make high frequency PCBs include:
- Rogers 4350B HF, RO3001, RO3003;
- ISOLA IS620 Electronic Fiber Glass;
- Taconic RF-35 Ceramic;
- Taconic TLX.
High frequency PCBs can be used in the following scenarios:
- High frequency data line
- Automotive Radar System
- Cellular telecommunication system
- Power Amplifiers and Antennas
- E-band point-to-point microwave links
- RFID tags
- mmWave applications
IMS PCB: Types of Enhanced Standby Time
As PCBA companies increasingly prioritize the thermal management performance of PCBs, IMS PCB – a circuit board type with efficient thermal management capabilities – has become highly valued. Thanks to this unique advantage, IMS PCBA can maximize the power of electronic products. FS Technology has summarized the advantages and application areas of this type of PCB board as follows:
Advantages of this type of printed circuit board:
- Excellent thermal conductivity: The thermal conductivity of aluminum substrate IMS is 8-12 times that of FR-4, with a thermal conductivity as high as 2.2/m·K;
- Obvious heat dissipation efficiency: The use of SMT PCB assembly technology can reduce the volume of the finished product by increasing the density of components, but it also makes the PCB lose its heat dissipation capability. IMS Insulated Metal Substrates are experts in addressing these deficiencies. The use of this type of circuit board plays an important role in dissipating the heat generated by the operation of electronic components and accelerating the reduction of the operating temperature of electronic components;
- Ultra-large current carrying capacity: For the metal substrate of IMS, it can carry a higher current with the same thickness and the same trace width, allowing the use of a voltage of 4500V;
- Premium Substrate Material: This type of PCB is typically filled with aluminum oxide, aluminum nitride, boron nitride, magnesium oxide, or silicon oxide.
HDI PCB: Circuit type designed for compact electronic equipment
This circuit board type adopts high-density interconnection technology and uses a traditional double-sided PCB as the substrate, which is then formed by multiple layers of lamination. Compared to traditional FR-4 circuits, this board is thinner, lighter, smaller, and denser. With the increasing demand for miniaturization of electronic products, electronic manufacturers have been improving their micro via, line width, line spacing, and pad manufacturing capabilities, resulting in the transformation towards HDI PCB. This type of circuit board is often used in high-end control systems.
Different types of printed circuit boards that FS Technology can produce has greatly explained. We are offering PCB-based services with great accuracy and high-quality features since it is a reliable PCB provider in the industry that offers PCB manufacturing services to users’ requirements and demands. FS Technology is serving as one-stop solution PCBA service provider and also an overseas projects manager. We are equipped with professional engineers and the latest machines that are commonly used in the PCB industry to create professional PCBs.