Advantages and uses of aluminum substrate

Many small partners who have just been involved in the PCB industry often encounter the term aluminum substrate

What is aluminum substrate
The aluminum substrate is a metal-based copper clad laminate with good heat dissipation function. Generally, a single panel is composed of a three-layer structure, which is a circuit layer (copper foil), an insulating layer and a metal base layer. Commonly found in LED lighting products. There are two sides, the white side is for soldering the LED pins, and the other side is the natural color of aluminum. Generally, the thermal conductive paste will be applied to contact with the thermal conductive part. Currently there are ceramic substrates and so on.

Generally, the aluminum substrates we encounter are single-layer aluminum-based PCB boards, which are one of the PCB boards. Aluminum substrates have good thermal conductivity, so they are a general term for PCB boards that are specifically used in the LED industry. At present, the most commonly used LED aluminum substrates have front and back sides. The white side is for soldering the LED pins, and the other side shows the natural color of aluminum. Generally, a thermal conductive paste is applied to contact the thermal conductive part. The metal base copper clad laminate with good heat dissipation function generally consists of a three-layer structure, which is a circuit layer (copper foil), an insulating layer and a metal base layer. For high-end use, there are also designed as double-sided panels, and the structure is circuit layer, insulating layer, aluminum base, insulating layer, and circuit layer. Very few applications are multi-layer boards, which can be formed by bonding ordinary multi-layer boards with insulating layers and aluminum bases.
 
The PCB board we talked about most are generally copper substrates, and they are also divided into single-layer and multi-layer boards according to the number of layers. Compared with copper substrates, aluminum substrates have relatively special materials and better heat dissipation , So the price will be relatively more expensive.
 
Advantages of PCB aluminum substrate
Compared with the traditional FR-4, the aluminum substrate can minimize the thermal resistance, so that the aluminum substrate has excellent thermal conductivity; compared with the ceramic substrate, its mechanical properties are extremely good.
In addition to good heat dissipation performance, aluminum substrates also have the following advantages:

  • Comply with RoHS environmental protection requirements
  • Suitable for SMT process
  • Higher current carrying capacity
  • Extremely effective treatment of thermal diffusion in the circuit design plan, thereby reducing the operating temperature of the module, extending the service life, and improving the power density and reliability;
  • Reduce the assembly of heat sinks and other hardware (including thermal interface materials), reduce product volume, and reduce hardware and assembly costs; optimize the combination of power circuits and control circuits;
  • Replace fragile ceramic substrates to obtain better mechanical durability.

 
The main applications of aluminum substrate
1. Lighting products, high-power LED PCB assembly lighting products.
2. Audio equipment, preamplifier, power amplifier, etc.
3. Power equipment, DC/AC converters, rectifier bridges, solid state relays, etc.
4. Communication products, high-frequency amplifiers, filter appliances, and transmission circuits.