Benefits of Multilayer Printed Circuit Boards：
Most PCB manufacturers are finding the demand for multilayer boards increasing by leaps and bounds. This growing demand is fed by the need for smaller, lighter boards for use in electrical devices, military equipment, healthcare miniaturization, and an expanding market for smart devices incorporated in home automation systems.
Smartphones and computers are perfect applications for multilayer PCBs with their need for compactness and light weight, yet sophisticated functionality.
From a technical standpoint, there are numerous advantages to the use of multilayer designs, over and above saving space and weight:
By incorporating multiple layers in a single PCB, boards can increase functionality.
Manufacturing processes for multilayer boards result in high-quality, reliable end products.
Multilayer boards by their innate electrical properties provide high capacity and high speed in a smaller footprint.
Higher density of assembly
Connectors required for multiple separate PCBs are reduced or eliminated, simplifying construction and further reducing weight.
Multilayer PCBs can be manufactured in both rigid and flexible construction. Be advised though, that the more layers incorporated in a flex PCB, the less flexible it becomes.