Multilayer PCB – Expanding the rule of Electronics in our Mechanical world

It is all about layering whether you are bracing for a winter storm or building an equipment that will enhance the quality of lives. Printed Circuit Boards have been around for decades now, and they have played a crucial role in transforming the human civilization from very rudimentary horse driven wagons to smart cars.

A PCB board with three or more layers is called Multilayer PCB. The layers in a multilayer board are connected via copper plated holes. Based on the design complexity and requirement more layers can be added. A 20 layer or 40-layer PCB is not uncommon. PCB Manufacturers keep pushing the technology boundaries to manufacture circuits boards that challenge the traditional multilayer PCB manufacturing processes to develop ‘smarter’ circuit boards. Concepts like AR, IoT, and Metaverse are further going to push the limits of printed circuit board technology in the coming years.

Structure of Multilayer PCB

There are two basic stack-up methods – Foil Method and Caped Method. At CCI Canadian Circuits, we prefer foil method.

High Tg FR-4 is the favoured material for the core whereas fibre glass epoxy resin is preferred material for the dielectric. Materials like Rogers, Arlon, Aluminum, Omegaply are also used for conductive materials and substrate.

One of the major quality challenges for the Multilayer PCB manufacturers face is the crosstalk between the layers. To manufacture a reliable and efficient PCB, it is vital to ensure there is very low to zero crosstalk, electromagnetic emissions and signal integrity meets the industry standards. Stack up information— Core, Prepreg (thickness, materials)—also plays a crucial role in Multilayer Circuit Board manufacturing. One more very important aspect for high performing PCB is the correlation between thickness and impedance. One must remember an increase in 0.025mm of the thickness would increase the Impedance by 3 ohms.

Here is a quick table to see how many routing layers there are in 4,6,8 and more layer of boards:

Where are Multilayer PCBs found?

Multilayer Printed Circuit Boards find application in a variety of industries and equipment. Everyday appliances like microwave, TV, air conditioners to complex medical equipment like X-ray machines, CAT scans etc., have Multilayer circuit boards in their core. Wherever there is a design requirement for a small, lightweight yet reliable electronic components, Multilayer PCB is the highly recommended PCB type.  

Here is a list of few industries where Multilayer PCB is used:

• Automotive
• Aerospace
• Medical
• Communication
• Telecommunication
• Industrial equipment
• Consumer Electronics

To learn more about our Multilayer PCB manufacturing, send us an email at sales@canadiancircuits.com