The PCB material, insulation between layers, is a poor heat conduct. The ability of the copper to transport heat is far better.Typical for an FR4 material the thermal conductivity λ~ 0.22 W/mK, and for copper it is λ~ 390 W/mK.To get more news about Cavity PCB, you can visit pcbmake official website.

A full-size heatsink can be external or internal.
– Internal it is Metal-Core layers or Thick-Copper layers.
– External it can be pre-bonded (IMS) or post-bonded.

Local Heat-Dissipation
Most common is the use of Thermal Vias. They can be mechanically drilled blind or through vias.Laser, stacked mVias, become more common, especially with low i/o pitch components.An alternative that will give better heat dissipation is the use of a local Cu-Coin.This can be a Bonded Cu-Coin, Press-Fit Cu-Coin or Embedded Cu-Coin.
Option 1: Heavy Copper PCB
-Boards design to carry high current
-Heat generated is distributed throughout heavy copper traces up to 210µm with UL approval.
-Boards to be designed with compatible material
-Higher heat dissipation traditionally needs external devices as well. As chassis or external heat sink.

Option 2: Metal Backed PCB
Application: Power Amplifier Module (RF board)

Key Attributes:
– Copper Based Metal Plate PCB:
Copper heatsink and RF-60 PTFE material. This is a ceramic filled fiberglass substrate.
Other materials can also be used.
-Controlled Depth Cavity where plated holes connect to the metal plate.
-Thick Copper Plate. Challenges:
-Mechanical Routing & Drilling. Need to handle both hard Cu & soft PTFE

Option 3: Coin Attachment
Coin Assembly onto Cavity PCB for Heat Dissipation:
-Most common with a Conductive Adhesive Layer
-More seldom with Solder Reflow Attachment. This need to be clarified with EMS, Assembly house.
– Also, a thick copper plate can be pretreated and contain towers that act as coins.

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