The substrate is the basic material for manufacturing PCB, and some important properties of the printed board largely depend on the substrate. Current PCB substrates can be divided into three categories: ordinary substrates, metal substrates and ceramic substrates, which can meet different needs and purposes. Today this article will mainly introduce the definition, type, material, application, structure and production process of MCPCB-metal core PCB.
What does MC PCB mean
A special printed circuit board that makes printed circuits on meta core copper clad laminates, it is called metal core printed circuit boards, referred to as metal core PCBs (MCPCB). Metal core printed boards are a category of printed boards. There are three common types: aluminum PCB, copper PCB, iron PCB.
What’s the type of MCPCB
What are the advantages of MCPCB
● Thermal expansion
Thermal expansion is the process by which a material expands when heated and shrinks when the material cools. Over time, this process can create weaknesses in the material, which ultimately leads to less efficient heat dissipation. Compared to conventional PCB materials such as ceramics and fiberglass, metal core PCBs such as aluminum PCBs are less prone to thermal expansion.
● Heat dissipation
For some products that require good electrical insulation and thermal conductivity, like double-sided PCB and multi-layer PCB,, metal core boards can quickly dissipate heat to avoid damage to components because they have certain thermal conductivity.
MCPCBs are produced to compensate for the shortcomings of weak heat dissipation of traditional substrate PCBs. Therefore, the application scenarios in MCPCBs are more extensive. For details, you can refer to “What are the applications of MCPCB?”
Aluminum, copper, iron are the normal materials of MCPCB. Aluminum is a metal commonly found in a variety of climates. This type of metal is also easy to mine and refine, which makes aluminum much cheaper to produce compared to other types of metals.
One of the great benefits of using aluminum for PCB circuit boards is the durability and strength it provides.
The lower density of metal adds greater durability, strength and resistance to the printed circuit board without any additional weight.
The metal is non-toxic and recyclable.
What are the applications of MCPCB
Communication power supply
Motor control for electric/hybrid vehicles
Solid state relays
Power supply equipment – voltage regulators, switching regulators, DC-DC converters
What is the base material of MCPCB
There are three main types of metal substrates: aluminum substrates, copper substrates, and iron substrates.
● Aluminum substrate
Good heat dissipation, relatively light weight, low cost. Mainly used in LED LCD TV, LED lighting, automotive, audio equipment, industrial power supply equipment and audio equipment, etc.
● Copper substrate
Good heat dissipation, good dimensional stability, but high cost and high quality. Mainly used in high-frequency circuits, precision communication equipment, high-power LED lighting, automotive lighting, etc.
● Iron substrate
Good magnetic conductivity, but easy oxidation and large mass. Mainly used in small precision motors and intelligent drives.
What is the structure of MCPCB
The metal base circuit board is a composite printing made of metal substrate, insulation dielectric layer and circuit copper layer.
① Circuit copper layer: Etching a circuit copper layer (usually using electrolytic copper foil) to form a printed circuit that is used to enable the assembly and connection of the device.
② Insulating layer: The insulating layer plays the role of bonding, insulation and thermal conduction.
③ Metal substrate: Considerating some factors like the thermal expansion coefficient, thermal conductivity, strength, hardness, weight, surface state and cost of the metal substrate to choose the best metal substrate. Generally, aluminum is the most ideal choice.
What is the thickness of MCPCB
Metal PCB substrate is composed of metal substrate (such as aluminum plate, copper plate, iron plate, silicon steel plate), high thermal conductivity insulation dielectric layer and copper foil. The insulation dielectric layer generally adopts high thermal conductivity epoxy glass fiber cloth bonding sheet or high thermal conductivity epoxy resin, the thickness of the insulating dielectric layer is 80μm-100μm, and the thickness of the metal plate is 0.5 mm, 1.0mm, 1.5 mm, 2.0 mm, 3.0 mm.
What is the thermal conductivity of MCPCB
Among the materials of MCPCB, the aluminum has the best thermal conductivity. The thermal conductivity of aluminum-based PCB refers to the heat dissipation performance parameters of aluminum substrates, which is one of the standards for measuring the quality of circuit boards.
The thermal conductivity of aluminum-based circuit boards varies from 0.1 to 2.5 according to the different applications. The thermal conductivity of aluminum-based circuit boards is determined by the thickness of copper foil and the insulation layer, which is 25mu, 35mu , 70mu, 105mu or more.
How to make metal core PCB
The whole process flow of metal core printed board (single-sided, aluminum-based): Cutting→ drilling positioning holes→ light imaging (film exposure development) → QC (quality inspection) → etching→ solder mask→ characters → QC→ Hot air leveling (or Shen Ni/Au, Shen Ag, Shen Sn, OSP) → Aluminum base surface treatment→ Contour processing (punching, punching shape) → Final inspection → packaging → shipment.
What is the difference between MCPCB and ceramic PCB
MCPCB uses metals such as copper, aluminum or iron as the substrate, and ceramic PCB uses ceramic as the substrate.
Metal PCB is generally composed of metal substrate, insulation dielectric layer and line copper layer, while ceramic PCB is composed of ceramic substrate, circuit layer and metal layer. The ceramic itself is insulating, so there is no need to make an insulating layer.
The price of ceramics is lower than that of copper and higher than that of aluminum.
Ceramic PCBs have stronger thermal conductivity and insulation than MCPCBs.
What is the difference between FR4 PCB and MCPCB
● Electrical conductivity: FR4 has low thermal conductivity, usually about 0.3W, while MCPCB has higher thermal conductivity, ranging from 1.0W-4.0W, the most common is about 2.0W.
● Plated through holes: FR4 PCBs typically use plated through holes. If desired, through-hole assemblies can be used. In MCPCB, plated through-holes are not suitable for single-layer PCBs. All components are surface mounted.
● Heat dissipation: Heat dissipation in FR4 PCBs usually includes vias for heat transfer. Longer drilling cycles add many processes. MCPCB materials provide their own heat dissipation. By drilling, deposition and electroplating processes are eliminated.
● Solder Mask: FR4 PCB solder mask is usually dark (green, red, blue, black). Usually applied to the top and bottom. MCPCB solder masks are almost exclusively used in LED circuit boards. Only available at the top.
● Thickness: FR4 PCBs are available in various material combinations and layer sizes in various thicknesses. MCPCB thickness variation is limited by available backplane thickness and dielectric plate thickness.
The MCPCB manufacturing and assembly company – IBE
As a professional PCBA manufacturer, IBE always provide best product customer service for our clients. In the past 18 years, IBE has always been committed to provide the one-stop PCBA service, including PCB manufacturing, PCB design, prototype PCB, PCB assembly and so on.
IBE can manufacture and assembly PCB of all materials like MCPCB(aluminum, copper or iron PCB), normal PCB , and ceramic PCB. Besides, IBE has strong R&D and production capabilities-14 SMT lines, 6 Dip lines, Lab, 75000 m²factory, and 4 product assembly production workshop.The most important one, our price is very competitive because we own the factory.
MCPCBs are a major technological innovation in the electronics manufacturing industry and a key component of LED products due to their strong heat dissipation capabilities. Therefore, it is not difficult to see that in the future, MCPCB will be one of the development trends.