The invention relates to a heat sink comprising a diamond-containing composite material. In addition to a diamond content of 40-90% by volume, the composite material further comprises from 0.005 to 12% by volume of a silicon-carbon compound, from 7 to 49% by volume of an Ag-, Au- or Al-rich phase and less than 5% by volume of a further phase, with the volume ratio of the Ag-, Au or Al-rich phase to silicon carbide being greater than 4 and at least 60% of the diamond surface being covered by the silicon-carbon compound. Preferred production processes include atmospheric pressure and pressure-aided infiltration techniques. The component is suitable, in particular, as heat sink for semiconductor components.