A thermal-interface-material (TIM)-free thermal management apparatus includes a thermally-conductive unitary structure having an integrated circuit (IC) side and cooling system side, the thermally-conductive unitary structure including a plurality of high aspect ratio micro-pillars or porous structures extending from the IC side and a cooling system extending from the cooling system side. The cooling system may be selected from the group consisting of: a vapor chamber, micro-channel cooler, jet-impingement chamber, and air-cooled heat sink. The cooling system and the plurality of high aspect ratio micro-pillars form part of the same homogenous and thermally-conductive unitary structure.