A LED module comprising at least one LED mounted on a thermo-conducting flat substrate, said LED module being adapted for being used together with a TIM and a heat sink, said thermo-conducting flat substrate being adapted for spreading heat from said LED module through said TIM to said heat sink, said thermo-conducting flat substrate comprising a plurality of fastener eyes, each of said fastener eyes being adopted for receiving a fastener such as a screw or a rivet for mounting said thermo-conducting flat substrate to said heat sink, wherein said thermo-conducting flat substrate comprises integrally formed deformable zones in vicinity of each of said plurality of fastener eyes, said integrally formed deformable zones being coherent with said thermo-conducting flat substrate.