Ceramic PCB
1. What is Ceramic PCB?



Ceramic PCB board is also called ceramic substrate or ceramic circuit board, ceramic copper coated plate, ceramic substrate refers to the copper foil directly bonded to alumina (Al2O3) or aluminum nitride (AlN) ceramic substrate or other ceramic substrate surface (single or double) on the special process board. The ultrathin composite substrate has excellent electrical insulation performance, high thermal conductivity, excellent soft brazing and high adhesion strength, and can be etched into a variety of graphics like PCB board, with great current-carrying capacity. Therefore, Ceramic PCB board has become the basic material of high power electronic circuit structure technology and interconnection technology.

Ceramic PCB Manufacturing & Assembly – One-stop service The ceramic substrate (ceramic PCB) refers to a special process board in which a copper foil is directly bonded to a surface of an alumina (Al2O3 ) or aluminum nitride (AlN) ceramic substrate (single or double-sided) at a high temperature. The ultra-thin composite substrate produced has excellent electrical insulation properties, high thermal conductivity, excellent solderability, and high adhesion strength, and can etch various patterns like a PCB board, and has a large current carrying current ability.

Ceramic PCB Circuit Board

2. The advantages and disadvantages of Ceramic PCB



(1) Ceramic PCB board has very good thermal conductivity and insulation performance. Ceramic PCB board is made of ceramic substrate, ceramic substrate itself has very good insulation and thermal conductivity, thermal conductivity of 25~230w, insulation resistivity is 10 minus 14 square, visible insulation performance is very good.

(2) The dielectric constant of ceramic PCB board is very low, the dielectric loss is small, has very good high frequency performance, the dielectric loss of alumina ceramic PCB board is less than 0.0003@1MHz, the dielectric loss of aluminum nitride ceramic PCB board is less than 0.0005@1MHz. Low dielectric loss, high frequency performance, is widely used in the field of high frequency communication.

(3) Ceramic PCB bonding force is strong, using bonding technology, copper foil will not fall off.

(4) Ceramic PCB has large on-board flow, 100A current continuously passes through 1mm0.3mm thick copper body, and the temperature rises about 17℃; when 100A current continuously passes through the 2mm0.3mm thick copper body, the temperature rises only about 5℃.

(5) Ceramic PCB board is with high temperature resistance, corrosion resistance, environmental protection, can work in a very complex environment, long-term high frequency, long service life.

Disadvantages: fragile, scrap rate is high, this is one of the main short comings of ceramic PCB board, which leads to the production of a small area of the circuit board, the general size is less than 120mm, special custom 200mm,230mm, the general price is more expensive, the board cost is higher. In addition, because ceramic PCB board is made of ceramic material, it does not have better toughness like FR4 board, so it can make more than one meter long and wide. Another point is that the price is expensive, the requirements of electronic products are more and more rules, ceramic circuit boards are still used in some relatively high-end products, low-end products will not be used.



3. Number of Ceramic PCB production layers



Ceramic PCB board can do several layers at most, how many layers can be done, is a lot of customers more concerned about the topic. Ceramic PCB board can be made of multiple layers, mostly using HTCC process and LTCC process, but the processing cost is high. At present, Hitech circuit has made 4 layers, 8 layers, 16 layers of Ceramic PCB board, and so on, so far the customer feedback is good.



AlN Ceramic circuit board

4. The introduction of Ceramic PCB board



Ordinary PCB is usually made of copper foil and substrate bonding, and the substrate is mostly glass fiber (FR-4), phenolic resin (FR-3) and other materials, adhesives are usually phenolic, epoxy, etc. In the process of PCB processing due to thermal stress, chemical factors, improper production technology and other reasons, or in the design process due to the two sides of the copper asymmetry, it is easy to lead to different degrees of PCB board warping.

And another PCB substrate - ceramic substrate, due to heat dissipation performance, current carrying capacity, insulation, thermal expansion coefficient, are much better than ordinary glass fiber PCB board, so it is widely used in high-power power electronic modules, aerospace, military electronics and other products.

Ceramic substrate and ordinary PCB using adhesive copper foil and substrate bonding together, Ceramic PCB is in the high temperature environment, through the bonding method of copper foil and ceramic substrate together, strong binding force, copper foil will not fall off, high reliability, stable performance in high temperature, high humidity environment.



5. Three materials of ceramic substrate



Al2O3

Al2O3 is the most commonly used substrate material in ceramic substrate because of its high strength and chemical stability compared to most other oxide ceramics in mechanical, thermal and electrical properties, and rich raw material sources, suitable for a variety of technical manufacturing and different shapes. According to the percentage of alumina (Al2O3) can be divided into: 75 porcelain, 96 porcelain, 99.5 porcelain. With different amounts of alumina, its electrical properties are almost unaffected, but its mechanical properties and thermal conductivity vary greatly. There is more glass in the substrate with low purity and the surface roughness is large. The higher the purity of the substrate, the cleaner, compact, the lower the dielectric loss, but the higher the price.

BeO

It has higher thermal conductivity than aluminum. It is applied to the occasions where high thermal conductivity is needed. It decreases rapidly after the temperature exceeds 300℃, but its toxicity limits its own development.

AlN

AlN are ceramics with aluminum nitride powder as the main crystalline phase. Compared with alumina ceramic substrate, the insulation resistance, insulation resistance and dielectric constant are higher. Its thermal conductivity is 7~10 times that of Al2O3, and its thermal expansion coefficient (CTE) is approximately matched with silicon wafer, which is very important for high-power semiconductor chips. In the production process, the thermal conductivity of AlN is greatly affected by the content of residual oxygen impurities, and the decrease of oxygen content can significantly improve the thermal conductivity. At present, it is no problem that the thermal conductivity of the production level reaches 170W/ (m·K).

For the above reasons, it can be known that alumina ceramics are in a leading position in the fields of microelectronics, power electronics, hybrid microelectronics and power modules due to their superior comprehensive performance. Compared with the same size on the market (100mm×100mm×1mm), different materials of ceramic substrate price: 96% alumina 9.5 yuan, 99% alumina 18 yuan, aluminum nitride 150 yuan, beryllium oxide 650 yuan, you can see that different substrate price gap is also relatively large.

Hitech Circuits is a professional and reliable manufacturer of Ceramic PCBs, with many years of experience in making Ceramic PCBs, which enables the manufacture of high technology, high quality and difficult performance boards, and guarantees the quality and reliability of every product delivered to customers. If you have the need to make Ceramic PCB, welcome to contact us!



Alumina Ceramic PCB

6. Application of Ceramic PCB



1. High power power electronics module, solar panel module, etc

2. High frequency switching power supply, solid state relay

3. Automotive electronics, aerospace, military electronics

4. High power LED lighting products

5. Communication antenna, automobile igniter



7. Why use Ceramic PCB instead of other PCB boards?



Ordinary PCB is usually made of copper foil and substrate bonding, and the substrate is mostly glass fiber (FR-4), phenolic resin (FR-3) and other materials, adhesives are usually phenolic, epoxy, etc. The main material of ceramic substrate is alumina (Al2O3), beryllium oxide (BeO), aluminum nitride (AlN) and other metal oxide ceramics, the performance of the two is quite different.

● Plate rigidity, ordinary PCB basically belongs to chemical fiber material, its environment, temperature, processing technology and other conditions, its rigidity is far less than ceramic substrate; The latter has strong thermal stability and small coefficient of thermal expansion, which can be used in harsher environments.

● Heat dissipation performance, ceramic substrate heat dissipation performance is excellent, very suitable for high-power device scenarios, and ordinary PCB is currently limited by material technology, far less than ceramic materials.

● Insulation performance, good insulation of ceramic substrate, high pressure resistance, effectively protect personal safety and equipment.

● The bonding force between ceramic substrate and copper foil is strong, the bonding technology is used, the copper foil will not fall off, which greatly improves the reliability of the plate



8. What are the characteristics of Ceramic PCB



● Good stability

The surface of this plate can play a very good flame retardant effect, and good fire resistance, not easy to melt, Ceramic PCB is all acid and alkali items and other chemicals, whether it is disinfectant or cleaning agent, the surface of the Ceramic PCB will not be affected.

● Easy to clean

The surface of the Ceramic PCB has a strong anti-corrosion function, so it is very convenient to clean, the use of washing solution cleaning will not cause any impact on the surface and color, and the surface is very tight, no penetration, not easy to adhere to dust, but also has moisture-proof performance.

● Beautiful

The plate before firing, can be painted on the surface of the pattern and pattern, so fired out of the Ceramic PCB picture color is very beautiful, and not easy to be damaged, such Ceramic PCB is very beautiful and generous, and most are used for decoration.

● Anti-static

Ceramic PCBs are antistatic materials.

● Resistance to scratch

The surface structure of this kind of plate is very special, even under the action of hard objects outside, it is not easy to cause damage.