Aluminum PCBs are aluminum based CCLs (CCL is a type of base material of PCBs). Aluminum PCBs are actually quite similar to FR4 PCBs. The basic structure of Aluminum PCBs is four layered. It consists of a layer of copper foil, a dielectric layer, an aluminum base layer and aluminum base membrane.

• Copper Foil Layer: the copper layer used is relatively thicker than normal CCLs ( 1oz-10oz). A thicker layer of copper means a larger current carrying capacity.

• Dielectric Layer: the Dielectric layer is a thermally conductive layer and is around 50μm to 200μm thick. It had a low thermal resistance and it suitable for its application.

• Aluminum Base: The third layer isthe aluminum base which is made up of aluminum substrate. It has a high thermal conductivity.

Aluminum Base Membrane Layer: Aluminum base membrane is selective. It has a protective role by keeping the aluminum surface safe from scraping and unwanted etching. It is of two types i.e. Lower than 120 degree or around 250 degrees (anti high temperature).