Thermal Pads
Thermal pads are used as an electrical isolation but thermal conductive material between the heat sink and the PCB or the IC. It provides a conformable mating between the surfaces where the micro surface irregularity is filled with soft & compressive nature of the Thermal pad and provides very good thermal conductivity. Options are available based on your requirement of thermal conductivity, thickness, adhesion on single side or both side, shore hardness of thermal pads etc. These are provided in customised die cuts based on your drawings.