Aluminum PCB Design: Stackup, Structure And Layers

Aluminum PCB consists of three layers: the copper layer, dielectric layer, and aluminum base layer. There can be a fourth layer, which is known as the aluminum base membrane layer. The membrane layer protects the aluminum from scraping, scratches, and unwanted etching.

Aluminum PCB Structure

               Aluminum PCB Stackup

        Schematic diagram of heat dissipation of aluminum Core PCB

  • Copper Layer: At the top of the aluminum PCB, there is a copper layer, which creates the circuit. The layer is common in all types of PCBs, including FR-4. It offers the electrical connection and conductivity of current among the components.
  • Dielectric Layer: Aluminum can also conduct electricity; therefore, a dielectric material is used between the copper layer and the aluminum layer. This layer can be of different materials depending on the temperature range. Although this layer is electrically insulated, it can conduct heat efficiently. It has excellent thermal conductivity to hold the heat from the components to the aluminum layer.
  • Aluminum Base Layer: This is the most crucial layer of the PCB. It provides thermal conductivity, durability, and strength to the PCB. The layer is made of aluminum substrate. The substrate can be of different types, such as Aluminum 505, Aluminum 6061, etc. You can choose the perfect aluminum substrate according to your requirements.
  • Aluminum Base Membrane Layer: The aluminum base film is selective. It has a protective effect by protecting the aluminum surface from scratches and unnecessary corrosion. It has two types, namely less than 120 degrees or about 250 degrees (high-temperature resistance)

Common LED PCBs or Aluminum PCBs have front and back sides. The white side is for soldering the LED pins, and the other side is the color of aluminum. Generally, a thermally conductive paste is applied to contact the thermal conductive part. Aluminum PCB is mainly used in LED lamps and audio equipment, power supply equipment, etc. The main advantages of aluminum PCB are fast heat conduction and good heat dissipation performance.