The primary importance that you should always give regarding the construction of anything is the quality of the materials used. Of course, the materials need to be correct as well. You cannot construct a building with high-quality glass for an example. So, both the material and the quality of the material need to be simply of the best quality.
With PCB or a Printed Circuit Board, this concept is exactly the same. It is highly important what the components and the quality of the materials that will be used on the Printed Circuit Board for increasing the effectiveness and longevity. There are multiple options of materials available when you are putting together a Printed Circuit Board. However, if you want your Printed Circuit Board to be highly operational, and also want it in working condition for a long time, the material of the circuit board holds the most importance.
Selecting the Best Printed Circuit Board Material for the Design
Given below are the steps in which you can correctly choose the material for your PCB manufacturing which will suit your design as well.
? Step 1: Choosing the best PCB construction
If the concept of buildings and constructions are used, the constructing process needs to be well ordered and properly defined. For example, a building will need to have a foundation of solid concrete at first, followed by fitting the frames of wood or steel, and ultimately do the floors and the roofing. Following this example, when it comes to the construction of a Printed Circuit Board, the fabrication process needs to be absolutely well maintained and proper. The process of fabrications needs to be followed in the way like having the substrate at first, followed by the laminate, followed by the solder mask, and ultimately, putting the silkscreen at last.
? Step 2: Knowing the use of the PCB components
The main use of the silkscreen is that it can identify the markings accurately which are extremely valuable for the proper assembly of the Printed Circuit Board. The use of the Solder mask is mainly for protection, with this layer acting as a barrier for the contaminants that can come from the outside. In this manner, with the use of the Solder mask, the necessary distance and isolation is created between the elements that are present on the surface. These elements mainly consist of the drill holes, copper traces, and pads. If we are talking about the foundation of the Printed Circuit Board or the integrity of the structure, the substrate and the laminate need to be on point.
? Step 3: Knowing why the material is important for PCB manufacturing
Only when the materials of the Printed Circuit Board are chosen in the best possible manner, that the efficiency of the board will be the best possible. The foundational elements can be easily chosen as per the different types of the board, and this will make sure that the functionality, manufacturability, and the life cycle of the board will be increased manifold.
To make sure that the material of the Printed Circuit Board is the best, one must be familiar with the different types of materials available for putting together a Printed Circuit Board. Also, the different types of Printed Circuit Boards should also be known properly.
? Step 4: Selecting the material of a Printed Circuit Board
If you want to get the overall efficiency of your Printed Circuit Board right, you have to know about the materials properly. The foundation of the Printed Circuit Board, which is also known as base by many people, is mainly composed of the laminate and core, where the latter is otherwise known as the substrate as we know it. The material of the substrate is mainly made up of a substance which is both dielectric and not conductive. Thus, the material of the substrate has to be selected very carefully, and usually, the dielectric constant gives the path to select a substrate.
The use of laminates is also very important, as it is used in mixtures with the substrates. The laminates mainly provide the material present in the surface, most commonly as copper foils. In some special cases, the construction of the Printed Circuit Board is done with the core material as laminates.
? Step 5: Knowing the PCB components
Read on to know about these components in extensive details.
As stated above, the main core structure in the Printed Circuit Boards are the substrates, usually, the typical composite structures made up of dielectric and non-conductive material are the substrates. These parts mainly contain glass weave, which is unwoven at times, and epoxy resin. The glass weave is often supplemented with the help of ceramic materials, as this will affect the dielectric constant to increase. Some of the property requirements of the Printed Circuit Boards are fulfilled with the help of the substrates, and this includes the transition temperature of the glass as well. This particular temperature is the exact temperature where the material is softened or deformed by the heat. As a result, the material can be customized at this point.
At present, there are multiple types of standard substrates available which are widely used in the fabrication process of the Printed Circuit Boards. Some popular varieties of these standard substrates are the CEM-1 thru CEM-5, G-10 and G-11, FR-1 thru FR-6, IMS or Insulated Metal Substrate, which is mainly Aluminium, PTFE or Polytetrafluoroethylene, Polyimide, RF-35, and Alumina. Substrates which are highly flexible in nature, such as the Kapton and Pyralux are also used. At present, the most common type of substrate used in the Printed Circuit Boards is the FR-4 type.
The manufacturing process of the laminates is slightly more complicated than the substrates. The manufacturing is done by applying external pressure, and the laminates mainly consist of the thermostat resin, and layers of papers and cloth. The usage of the laminates is very similar to the substrates, and the customized requirements of the Printed Circuit Board can be met by fulfilling the required properties. The laminates have multiple interesting properties, and these include incredible shear and tensile strength. The CTE, the transition glass temperature, and the coefficient of thermal expansion are other important factors to keep in mind. The material used in laminates is also dielectric in nature, and they are mainly polytetrafluoroethylene, or commonly known as Teflon, CEM-1, CEM-3, FR-1, and FR-4. The other materials that are also common are the G-10, CEM-1 thru CEM-5, and FR-2 thru FR-6.
When put together, the substrate and the laminate comprise the majority of the Printed Circuit Board. The basic properties of the circuit boards define the primary mechanical, thermal and electrical circuit board properties. These properties have to be kept in mind, and the laminates and the substrates have to be used in conjunction. When the conjunction is done in the correct proportion, with the board type being accurately chosen, you can choose the design material for your Printed Circuit Board in the best possible manner.
? Step 6: Knowing the classification of Printed Circuit Boards
The Printed Circuit Boards can be classified and grouped according to a multiple number of ways. The criteria for the classification of the circuit boards are given below.
i. Location of the component ? The classification of the Printed Circuit Board can be done based on whether the component location is embedded, or single-sided, or double-sided.
ii. The stackup ? Based on this, the Printed Circuit Boards can be either of a single layer, or can be multilayered.
iii. The design ? When design is considered, the Printed Circuit Boards can be classified as custom, special, and module based.
iv. The bending ability ? Based on the bending nature and bending capability, the circuit boards are mainly classified as flex, rigid, and rigid-flex.
v. Overall strength ? The Printed Circuit Boards can either be mechanically strong, or electrically strong.
vi. The electrical functionality ? Based on this criterion of classification, the Printed Circuit Boards can be grouped as microwave, high density, high power, and high frequency.
Some of the criteria of classification mentioned above are considered to be not upto the mark. This is because some of these classification criteria do not actively involve the material of the Printed Circuit Board. For example, the criteria like overall strength and the bending ability are termed as good when the physical capability is measured. However, these same criteria will be useless to determine how the actual functioning of the Printed Circuit Boards is taking place. Following this example, the criteria of electrical functionality is directly determining the functionality of the Printed Circuit Board. In such cases, this criterion can be said to be an important one which should determine the material of the Printed Circuit Board.
When the functionality of the Printed Circuit Board is concerned, the board types can be classified as given below.
i. High Speed or High Frequency ? The boards in such groups can easily contain the frequencies which belong in the range of 500 MHz to 2 GHz.
ii. High Current or High Power ? The boards which fall into this category are able to withstand high currents. Therefore, the width of the traces is required to be thick, and the copper needs to be thick as well. These board types can also carry string current and can easily get rid of the accumulating high temperatures.
iii. High-Density Interconnect and High Density ? The types of boards falling into this category are usually complex in nature, and the traces are pretty thin in these board types. The materials used in this type of boards are performance friendly and enhancing, and laser microwaves are also utilized.
iv. Microwave ? The boards used in a microwave generally belong to the Printed Circuit Board types where the speeds of the signals vary from 1 GHz to over a few hundred GHz currently. Normally, the spectrum of the microwave belongs in the 300 MHz to 300 GHz range.
All of the types of boards mentioned above can be used for selecting the material for the Printed Circuit Boards, so that both the design and the efficiency of the circuit board is top notch.
Tip: The Best Printed Circuit Board Material
By now you know that the type of the board is also important to determine the materials for the Printed Circuit Board. The materials of the circuit board can be identified as per the typical properties of the physical characteristics. When the analysis of the substrate and the laminate to be used are determined, these characteristics are quite important. In many cases, the comparison between the different types of circuit boards is done via metrics. The ability of the circuit boards for tolerating heat, and the dielectric constant are the main reasons as how the comparisons of the Printed Circuit Boards take place.
There are a huge number and possibilities of combinations which can constitute the different types of materials used in the Printed Circuit Boards. It is not possible to explain all of them in detail. In most cases, not every one of them needs to be known as well. However, it is essential to know about the circuit board materials which are used for the special cases and the normal cases of the types of Printed Circuit Boards. This way, selecting the design of these boards becomes essentially easy. Multiple evaluations of the Printed Circuit Board should be done, and the main basis should be the proportionate conjunction of laminates and substrates. Make sure that the requirements in the design of the board are fulfilled in such a manner as it promotes the capabilities of the board.
As you can see, the construction of a Printed Circuit Board ultimately determines its functionality, life cycle, and the manufacturability as well. Hence, the selection of the material of the Printed Circuit Board is very critical. If you are a consumer, you should choose industries where the Printed Circuit Board manufacturing is done properly, with options of customized materials of circuit boards, which are flex and rigid as well. Any professional in this field will be able to collect the proper files, and designing of the Printed Circuit Boards are also done with modern upgraded software technology.
Therefore, before deciding to manufacture a Printed Circuit Board, try looking at the types of board, the material which is used, the quality of the material, and the design. Together, if they form a combination that has great efficiency, will run for long, and has great flexibility in terms of utility, and comes with proper design and manufacturability, it is the Printed Circuit Board to choose among the rest.