Thermal Conductivity of MCPCB

The aluminum core PCB(MCPCB) is a metal-based copper-clad laminate with good heat dissipation. In general, a single-sided MCPCB consists of three-layer structure, which is a circuit layer (copper foil), an insulation layer, and a metal substrate.

For high-end use is also designed as a double-sided board, the structure of the circuit layer, insulation layer, aluminum, insulation, circuit layer. A very small number of applications are multilayer boards, which can be made of ordinary multilayer boards with insulating layers and aluminum substrates.

MCPCB construction

1.  Circuit Layer

The circuit layer (usually electrolytic copper foil) is etched to form a printed circuit for the assembly and connection of the device. Compared with traditional FR-4, with the same thickness, the same line width, aluminum core PCB(MCPCB) can carry a higher current.

2. Dielectric Layer

Dielectric layer is the core technology of aluminum core PCB(MCPCB), which mainly functions as bonding, insulation and heat conduction. MCPCB dielectric is the largest thermal barrier in the power module structure. The better of thermal conductivity of dielectric layer, the more conducive to the dissipation of heat generated during the operation of the device, the more conducive to reducing the operating temperature of the device, so as to achieve the purpose of increasing the power load of the module, reducing the size, extending the life, increasing the power output, etc..

3. Metal Substrate Layer

Which kind of metal is used for the insulating metal substrate depends on the comprehensive consideration of the thermal expansion coefficient, thermal conductivity, strength, hardness, weight, surface condition and cost of the metal substrate. Under normal circumstances, considering the conditions of cost and technical performance, aluminum sheet is an ideal choice. Available aluminum plates are 6061, 5052, 1060, etc. If there are higher requirements for thermal conductivity, mechanical properties, electrical properties and other special properties, copper plates, stainless steel plates, iron plates and silicon steel plates can also be used.

The thermal conductivity of metal core PCB(MCPCB):

Item Test Condition Units KS-101 KS-110 KS-111
Thermal Conductibility A W/m.k 1.0-1.8 1.0-2.0 1.8-3.0
Peel Strength A(After thermal stress N/mm 1.3 1.8 1.5
Thermal Stress 288℃ S 30S 90S 120S
Surface Resistance  C-96/35/90 E-24/125  107  107  107
Volume Resistivity  C-96/35/90 E-24/125  105  105  105
Electrical Strengthen  A  KV/mm  30 30  30
Flammability  UL94  –  V-0  V-0  V-0
Tg  A  130  100  100
Moisture Absorption  D-24/23 %  0.1  0.03  0.03
CTI IEC60112 V 250 600 600
Item Test Condition Units KS-112 KS-113 KS-114
Thermal Conductibility A W/m.k 2.5-5.0 1.5-2.0 1.5-2.0
Peel Strength A(After thermal stress N/mm 1.3 1.3 1.3
Thermal Stress 288℃ S 120S 120S 600S
Surface Resistance  C-96/35/90 E-24/125  107  107  107
Volume Resistivity  C-96/35/90 E-24/125  105  105  105
Electrical Strengthen  A  KV/mm  30 30  30
Flammability  UL94  –  V-0  V-0  V-0
Tg  A  100  170  100
Moisture Absorption  D-24/23 %  0.03  0.03  0.03
CTI IEC60112 V 600 600 600