Aluminum Printed Circuit Board: Introduction
Aluminum PCB manufacturers generate aluminum alloy after several heat treatments and pre-drawing processes. These steps are imperative to ensure the quality of Aluminum alloy. You cannot compare its strength with either the 2XXX system or the 7XXX system.
However, manufacturers do enjoy the processing performance, electroplating characteristics, welding power, and corrosion-resistant of its silicon and magnesium alloy. Furthermore, it offers toughness, compact material, no deformation and defect-free material.
Polishing and coloring are also easy and efficient. The amazing oxidation effect further adds to its appeal.
Aluminum PCB Manufacturing: Structure of Aluminum PCB
The copper-clad laminate (CCL) is the basis of the aluminum PCB structure. It consists of the aluminum membrane, aluminum base, dielectric layer, and the copper foil. In the picture below, you can see the structure of the copper-clad laminate.
Copper Foil layer
The Aluminum CCL has the same copper foil layer as that of any other type of PCC’s CCL. It is the current’s objective to provide a large current carrying capacity. Due to this, choosing a thick copper circuit is a good decision in aluminum PCB manufacturing.
Generally, the manufacturer prefers the thickness between 1oz to 10oz. It is important for the copper foil’s backside to go through different oxidation treatment. The treatment involves chemicals as well.
Likewise, the front side goes through brass plating and zincing. The main reason for front treatment is to improve the peel-off strength of the aluminum Printed Circuit Board.
Dielectric Layer
The next layer, is the dielectric layer. It compromises of a composed thermal dielectric material. This material has a low thermal resistance. Generally, it has a thickness ranging from 50μm to 200μm. The thickness depends upon the type of the Printed Circuit Board and the consumer’s demand.
This layer seems to be the aluminum Printed Circuit Board core technology. It has the same functionality as that of the anti-thermal aging. Moreover, it has the capacity to withstand thermal stress as well as mechanical stress.
Aluminum Base Layer
When we say aluminum base layer, we actually mean the aluminum substrate. This substrate is supporting all the components present on the board. It binds the components to the board. It is imperative for this substrate to be highly thermally conductive.
Base layer also needs to be suitable for the different mechanical processes including cutting, punching, and drilling.
Base Membrane
The aluminum base pays an important role in the protection of PCB’s aluminum surface. It ensures that the surface is safe from agent etching and scraping. There are two main types of base membrane, first ordinary and second anti-high temperature.
Ordinary membrane usually withstands temperature lower than 120°C. On the contrary, the anti-high temperature can withstand up to 250°C.
The anti-high type is the best choice for hot air solder levelling.
