What should be the thermal conductivity of ceramic PCBs?

The high thermal conductivity of ceramic PCBA may be the main reason why more industries are turning to ceramics in their PCBs and packaging, as this substrate has significant advantages over traditional materials in this regard. Better CTE matching and sealing will only increase the attractiveness of these materials.

The challenge is that ceramic substrates and your PCBA manufacturer produce circuit boards that are much more expensive than traditional PCB materials, and the materials used in traditional PCB production may significantly increase during mass production. However, the benefits of ceramic plates and the demand for improving thermal conductivity are so great that any company capable of using ceramic plates may do so out of necessity.

How to estimate the level of thermal conductivity

At MCL, we can estimate the thermal conductivity level of the main types of ceramic plates, but the final value will vary depending on manufacturing process, grain size, and composition. Although we may not know the exact value of the board, please review the range of values agreed upon by the experts below:

Aluminum nitride: One of the most popular but expensive ceramics - aluminum nitride - has a thermal conductivity that many people believe exceeds 150 W/MK, usually around 180 W/MK. However, research has found that the values at room temperature range from 80 W/MK to 200 W/MK, and when approaching 100 degrees Celsius, the values decrease by more than one-third.

Aluminum oxide: Another type of primary ceramic aluminum oxide has a thermal conductivity range of 18 to 36 W/MK at room temperature.

Other material temperature ranges: We can determine other temperature ranges at room temperature, including 184 to 300 for beryllium oxide, 15 to 600 for boron nitride, and 70 to 210 W/MK for silicon carbide.

Due to the significant changes, it is difficult to determine the actual thermal conductivity. Your best approach is to conduct your own tests, record the values you obtain, and use them in future calculations.

Application of Ceramic PCB