Copper core PCB is a copper substrate + Insulated layer + copper.

Copper core PCB is a copper substrate + Insulated layer + copper circuits layer PCB, also, it is called copper substrate pcb, copper based pcb, copper clad pcb.

Copper core PCB is one of the most expensive metal substrates, and its thermal conductivity. Is many times better than that of aluminum and iron substrates. It is suitable for high frequency. 

Circuits, high and low temperature changing regions and the heat dissipation and building. Decoration industries of precision communication equipment, the circuit layer of copper substrate is required to have a large current-carrying capacity, so a thick copper foil should be used, the thickness of which is generally 35 m ~ 280 m; Thermal insulation layer is the core technology of copper substrate too. The core thermal Conductivity is composed of aluminum trioxide and silicon powder and polymer filled with Epoxy resin, the thermal resistance is low (0.15), viscoelasticity is excellent, and it has the Ability to resist thermal aging. It is able to withstand mechanical and thermal stress. Metal base is the support member of copper PCB. It is required to have high thermal Conductivity, generally copper sheet is used because copper can provide better thermal Conductivity, suitable for drilling, punching, shearing and cutting and other conventional Machining.