Thermal Pad
Thermal pads are used to bridge air gaps and surface irregularities. In particular, when no direct contact is possible between the heatsink and the surface of a computer chip. To enable the best possible thermal conduction, highly thermal conductive materials, like silicone, graphite, as well as metals are used. Typical applications are memory chips, GPUs, and MOSFETs. In summary, any computer chip, whose cooling system was made to use thermal pads.