I. Aluminum Substrate

Aluminum substrates are made of aluminum-based material with strong heat dissipation capabilities, making them commonly used in LED lighting products. They feature two sides: the white side for soldering LED leads, and the other side retaining the natural aluminum color. Typically, thermal paste is applied to the conductive side for contact with heat-dissipating components.

Aluminum substrate boards are also a type of metal-clad laminate with excellent heat dissipation properties. Single-sided boards typically consist of a three-layer structure: copper foil (circuit layer), insulating layer, and metal base layer. Double-sided boards used in high-end products feature a structure of circuit layer, insulating layer, aluminum base, insulating layer, and circuit layer. A very small number utilize multilayer boards, generally composed of standard multilayer boards, insulating layers, and aluminum bases laminated together.

II. Copper Substrates

Copper substrates are the most expensive among metal substrates, offering thermal conductivity significantly superior to aluminum or iron substrates. They are commonly used in high-frequency circuits, areas with extreme temperature fluctuations, precision communication equipment heat dissipation, and architectural decoration industries.

Due to the high load-bearing capacity of copper substrate circuit layers, copper foil thicknesses ranging from 35μm to 280μm are typically employed. Its insulating layer represents core technology, composed of a polymer matrix filled with aluminum oxide and silica powder, reinforced with epoxy resin. This layer exhibits a thermal resistance of 0.15, excellent viscoelastic properties, resistance to thermal aging, and the ability to withstand mechanical processing and thermal stress.

Due to the inherent properties of copper versus aluminum and the corresponding differences in PCB processing techniques, copper substrates for LED automotive headlights offer superior performance advantages over aluminum substrates.