Custom Aluminum Printed Circuit Boards – Copper pcbPosted on 2020-02-12
Custom Aluminum Printed Circuit Boards :Copper PCB
The Aluminum PCB and the copper pcb are metal-based copper-covered boards with good heat disappearing (or wasting) functions. Generally, a single panel is composed of a three-layer structure, which is a circuit layer (copper foil), an insulating layer and a metal base layer. For high-end use, there are also double-panel designs, the structure is circuit layer, insulation layer, aluminum-based or copper-based, insulation layer, circuit layer. Very few computer programs are multilayer boards, which can be made by mixing common multilayer boards with insulation, aluminum or copper
The LED aluminum is the PCB, which is also the meaning of the printed circuit board, but the material of the circuit board is aluminum mix/mixture (of metals). In the past, the material of our general circuit board was glass fiber, but because the LED creates heat, the circuit board for LED lamps is generally Aluminum or copper can permit the flow of heat quickly. Circuit boards for other equipment or electrical appliances are still glass fiber boards!
Aluminum substrate / copper substrate / working principle
The Aluminum PCB or Copper PCB can minimize the thermal resistance and make the aluminum substrate have excellent thermal conductivity; compared with thick-film ceramic circuits, its mechanical properties are extremely excellent.
In addition, aluminum and copper substrates have the following unique advantages:
Ø Meet RoHs requirements;
Ø More suitable for SMT process;
Ø Extremely effective treatment of thermal diffusion in the circuit design scheme, thereby reducing the module operating temperature, extending the service life, and improving power density and reliability;
Ø Reduce the assembly of radiators and other hardware (including thermal interface materials), reduce product size, reduce hardware and assembly costs; Ø Optimize the combination of power circuits and control circuits
Ø Replace fragile ceramic substrates to obtain better mechanical durability.
What is the composition of aluminum substrate / copper substrate
Ø Line layer
After etching, a printed circuit is formed to realize the assembly and connection of the device. Compared with the traditional FR-4, with the same thickness and the same line width, the Aluminum PCB can carry a higher current
The insulation layer is the core technology of the aluminum substrate, which mainly plays the functions of bonding, insulation and heat conduction. The aluminum substrate insulation is the largest thermal barrier in the power module structure. The better the thermal conductivity of the insulation layer, the more favorable it is to spread the heat generated during the operation of the device, and the lower the operating temperature of the device, so as to increase the power load of the module, reduce the volume, extend the life, and increase the power output .
A typical motor controller module uses a large number of heat sinks, thermal interface materials and other accessories. The module is bulky, the structure is complex, and the assembly cost is high. The aluminum substrate on the left side has a Highly automated surface-mount products, the entire product has reduced from 130 to 18 components, the power load has increased by 30%, and the module size has been greatly reduced. This type of high power density module can only be qualified with an aluminum substrate with high thermal conductivity.
Ø Metal substrate
What 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 state and cost of the metal substrate.
In general, considering the conditions such as cost and technical performance, aluminum plate is an ideal choice. Available aluminum plates are 6061, 5052, 1060 and so on. 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.
Ø Characteristics of aluminum pcb sheet
Aluminum pcb / copper pcb (metal-based heat sink (including aluminum substrate, copper substrate, iron substrate)) is a low-alloyed Al-Mg-Si series high-plasticity alloy plate (see the figure below for structure), which has good thermal conductivity 、 Electrical insulation performance and machining performance. Compared with the traditional FR-4, the aluminum pcb adopts the same thickness and the same line width. The aluminum pcb can carry a higher current. The aluminum substrate can withstand voltages up to 4500V and the thermal conductivity is greater than 2.0, mainly aluminum pcb in the industry, copper substrates have strong heat dissipation, and are mainly used in high-power products
Such as: street lamp aluminum substrate
● Using surface mount technology (SMT);
● Extremely effective treatment of thermal diffusion in circuit design schemes;
● Reduce product operating temperature, improve product power density and reliability, and extend product life;
● Reduce product volume, reduce hardware and assembly costs;
● Replaces fragile ceramic substrates for better mechanical durability. structure
Aluminum-based composite copper board is a metal circuit board material, consisting of copper foil, thermally conductive insulation layer and metal substrate. Its structure is divided into three layers:
Cireuitl.Layer circuit layer: It is equivalent to a general copper clad copper plate.
DielcctricLayer insulation layer: The insulation layer is a layer of low thermal resistance thermally conductive insulating material. Thickness: 0.003 ”to 0.006” inches is the core technology of aluminum-based copper clad plate, which has obtained UL certification. BaseLayer: It is a metal substrate, usually aluminum or copper. Aluminum based copper clad laminate and traditional epoxy glass cloth laminate.
PCB materials have incomparable advantages compared to other materials. Suitable for surface mount SMT technology of power components.
No heat sink is needed, the volume is greatly reduced, the heat dissipation effect is excellent, and the good insulation performance and mechanical performance.
Aluminum substrate for fluorescent lamps
The LED die substrate is mainly used as a medium for deriving thermal energy between the LED die and the system circuit board. The LED die substrate is combined with the LED die through a process of wire bonding, eutectic or multi-crystal. Based on thermal considerations, the LED chip substrates on the market are mainly ceramic substrates, which can be roughly divided into three types: thick-film ceramic substrates, low-temperature co-fired multilayer ceramics, and thin-film ceramic substrates. For high-power LED components, a thick-film or low-temperature co-fired ceramic substrate is often used as the die heat dissipation substrate, and then the LED die is combined with the ceramic substrate by gold wire. As mentioned in the introduction, this gold wire connection limits the effectiveness of heat dissipation along the electrode contacts. Therefore, both domestic and foreign manufacturers are working hard to solve this problem. There are two solutions. One is to find a substrate material with a high heat dissipation coefficient to replace alumina, which includes a silicon substrate, a silicon carbide substrate, an anodized aluminum substrate, or an aluminum nitride substrate. Among them, silicon and silicon carbide substrates are semiconductors. Characteristics, making it face a more severe test at this stage, and the anodized aluminum substrate is easily connected due to fragmentation due to the insufficient strength of the anodized oxide layer, which limits its practical application. Therefore, at this stage, The more mature and more commonly accepted is aluminum nitride as the heat sink substrate; however, currently limited to aluminum nitride substrates are not suitable for traditional thick film processes (the material must be heat-treated at 850 ° C after silver paste printing)
, So that it has a problem of material reliability), therefore, the aluminum nitride substrate circuit needs to be prepared by a thin film process. The aluminum nitride substrate prepared by the thin film process greatly accelerates the efficiency of the heat from the LED die through the substrate material to the system circuit board, so the burden of heat from the LED die through the metal wire to the system circuit board is greatly reduced, thereby achieving high heat dissipation. Effect.
Application / Aluminum substrate / Copper substrate
Aluminum substrate use: Power Hybrid IC (HIC)
Input, output amplifier, balanced amplifier, audio amplifier, preamplifier, power amplifier, etc.
Switching regulator `DC / AC converter` SW regulator, etc.
The high-frequency amplifier `filtering electrical device` reports the circuit.
Office automation equipment
Motor drivers, etc.
Electronic regulator `ignitor` power controller and so on.
CPU board `floppy disk drive` power supply unit, etc.
Converter `solid relay` rectifier bridge, etc.
With the promotion and promotion of energy-saving lamps, various energy-saving gorgeous LED lamps have been welcomed by the market, and aluminum substrates used in LED lamps have begun to be applied on a large scale.