The circuit layer (generally using electrolytic copper foil) is etched to form printed circuit for the assembly and connection of devices. Using the same thickness and wire width, the printed circuit board can carry higher current than the traditional fr-4.
Dielecric layer is the core of aluminum printed circuit board technology, mainly plays the role of adhesion, dielecric and thermal conductivity. Aluminum substrate insulation layer is the largest thermal barrier in power module structure. The better the heat conduction performance of the dielecric layer is, the more beneficial it will be for the heat generated during the device operation to diffuse, and the more beneficial it will be for reducing the operating temperature of the device, so as to improve the power load of the module, reduce the volume, extend the service life and increase the power output.
The metal used for the metal base insulation metal substrate depends on the comprehensive consideration of the thermal expansion coefficient, thermal conductivity, strength, hardness, weight, surface state and cost of the metal substrate.
At present, many double panel, multilayer board density, power, heat dissipation difficult. Conventional PCB substrates such as FR4 and CEM3 are poor conductors of heat. Partial heating of electronic equipment is not excluded, leading to high temperature failure of electronic components, and aluminum substrate can solve this problem of heat dissipation.
Thermal expansion is the common nature of matter, and the coefficient of thermal expansion of different materials is different. Aluminum based PCB can effectively solve the problem of heat dissipation, so that the components of the PCB thermal expansion and contraction of different substances to alleviate the problem, improve the durability and reliability of the whole machine and electronic equipment. In particular, solve the SMT (surface mount technology) hot expansion and cold contraction problem.
Aluminum based PCB, obviously the size is much more stable than insulation PCB. Aluminum printed circuit board, aluminum sandwich board, from 30 ℃ heating to 140 ~ 150 ℃, size of 2.5 ~ 3.0%.