PCB Capabilities
Aluminum PCB Manufacturing
Metal-core substrates for LED lighting and power electronics thermal management.
Aluminum PCBs — also called aluminum-backed PCBs, insulated metal substrate (IMS) boards or metal-core PCBs with aluminum base — use an aluminum plate as the substrate foundation instead of FR-4. A thin dielectric layer bonds the copper circuit to the aluminum base, creating a construction optimized for thermal management. The aluminum base conducts heat from power components through the board to a heatsink or enclosure, providing thermal performance that no organic laminate can match. AstroPCB manufactures aluminum PCBs for LED lighting, power electronics, motor drives and automotive applications.
Construction
An aluminum PCB consists of three layers: the aluminum base plate (typically 1.0-3.2 mm thick), a thin dielectric layer (75-200 microns of thermally conductive, electrically insulating material) and the copper circuit layer (1-4 oz copper, etched into the circuit pattern). The dielectric layer is the critical performance element — its thermal conductivity determines how effectively heat transfers from the copper circuit to the aluminum base. Standard dielectric thermal conductivity ranges from 1.0 to 3.0 W/mK, with high-performance dielectrics reaching 5-8 W/mK at premium cost.
Standard aluminum PCBs are single-sided: one copper circuit layer on one side of the aluminum base. Double-sided aluminum PCBs place circuit layers on both sides of the aluminum base, with plated through-holes penetrating the aluminum (which requires insulating the hole wall from the aluminum before plating). Double-sided aluminum PCBs are more complex and expensive but provide routing on both sides of the board.
Thermal performance
The thermal advantage of aluminum PCBs is significant. An FR-4 board has a thermal conductivity of approximately 0.3 W/mK through the thickness. A standard aluminum PCB with 1.5 W/mK dielectric and 1.6 mm aluminum base provides thermal resistance from the copper pad to the aluminum backside that is 5-10x lower than an equivalent FR-4 construction. For a power LED dissipating 3 watts, this difference can mean junction temperatures 20-40°C lower — directly extending LED lifetime and maintaining light output.
The aluminum base also acts as a heat spreader, distributing concentrated heat from individual components across a larger area before the heat reaches the heatsink or enclosure. This spreading effect reduces hot spots and improves the uniformity of the temperature distribution across the board.
LED lighting applications
LED lighting is the largest application for aluminum PCBs. High-power LEDs generate significant heat relative to their size — a single 10W LED die dissipates more heat per square millimeter than most power semiconductors. The LED junction temperature directly affects light output, color temperature, efficiency and lifetime. Aluminum PCBs keep junction temperatures low enough for reliable long-term operation without requiring individual heatsinks on each LED. Street lights, automotive headlights, architectural lighting, industrial lighting and commercial display lighting all use aluminum PCBs as the LED mounting substrate.
Power electronics applications
Motor drives, DC-DC converters, power supplies and battery chargers use aluminum PCBs when the power density exceeds what FR-4 with thermal vias can handle. The continuous thermal path through the dielectric to the aluminum base is more effective than thermal via arrays in FR-4 for concentrated heat sources. Aluminum PCBs also provide mechanical rigidity and flatness that facilitate heatsink mounting with consistent thermal interface contact.
Request an aluminum PCB quote
Specify the aluminum thickness, dielectric thermal conductivity requirement, copper weight and board dimensions. Upload design files for a DFM-reviewed quotation.