Characteristics, structure and function of aluminum substrate
The heat dissipation problem of LEDs is the biggest headache for LED manufacturers, but aluminum substrates can be used. Because aluminum has high thermal conductivity and good heat dissipation, it can effectively extract internal heat. The aluminum substrate is a unique metal-based copper clad laminate with good thermal conductivity, electrical insulation properties and machinability. The PCB should also be placed close to the aluminum base as much as possible to reduce the thermal resistance generated by the potting compound.
First, the characteristics of the aluminum substrate
1. Using surface mount technology (SMT);
2. Extremely efficient treatment of thermal diffusion in circuit design;
3. Reduce product operating temperature, increase product power density and reliability, and extend product life;
4. Reduce product size and reduce hardware and assembly costs;
5. Replace the fragile ceramic substrate for better mechanical durability.
Second, the structure of the aluminum substrate
The aluminum-based copper clad laminate is a metal circuit board material composed of a copper foil, a thermally conductive insulating layer and a metal substrate, and its structure is divided into three layers:
Cireuitl.Layer circuit layer: equivalent to ordinary PCB copper clad, line copper foil thickness loz to 10oz.
DiELcctricLayer insulation: The insulation layer is a low thermal resistance thermal insulation material.
BaseLayer base: It is a metal substrate, usually aluminum or copper. Aluminum-based copper clad laminates and conventional epoxy glass cloth laminates.
The circuit layer (ie, copper foil) is usually etched to form a printed circuit, so that the various components of the component are connected to each other. In general, the circuit layer is required to have a large current carrying capacity, so that a thick copper foil should be used, and the thickness is generally 35 μm. 280μm; thermal conductive insulation layer is the core technology of aluminum substrate. It is generally composed of special polymer filled with special ceramics. It has small thermal resistance, excellent viscoelasticity, anti-heat aging ability, and can withstand mechanical and thermal stress.
The thermal insulation layer of high-performance aluminum substrate uses this technology to make it have excellent thermal conductivity and high-insulation electrical insulation properties; the metal substrate is the supporting member of the aluminum substrate, which requires high thermal conductivity, generally aluminum plate Copper plates (where copper plates provide better thermal conductivity) can also be used, which are suitable for conventional machining such as drilling, punching and cutting. PCB materials have advantages that are unmatched by other materials. Suitable for surface mount SMT technology of power components. No need for a heat sink, greatly reduced size, excellent heat dissipation, good insulation and mechanical properties.