Novel Si/SiGe heterodevices with enhanced performance demand low thermal budget contact formation. CoSi 2 and TiSi 2 can meet this requirement. The investigation of self-aligned rapid thermal processes for the formation of CoSi 2 (at 600-650 °C) and TiSi 2 (at 650-750 °C) and their application to n-channel hetero field effect transistors and heterobipolar transistors (HBTs) is described and effects on the device performance are presented.Specific resistances of around 20 μΩ cm for CoSi 2 and 17 μΩ cm for TiSi 2 could be confirmed for the Si/SiGe heterosystem. Contact resistances on n + -phosphorous implanted layers below 6 μΩ cm 2 have been derived from TLM structures. The silicide formation is severely affected by SiGe. Therefore the compound formation of CoSi 2 in the Co/Si and the Co/Si 1 - x Ge x system has been investigated and compared as a function of annealing time in a temperature range from 400 to 600 °C. X-ray diffraction measurements on SiGe layers confirmed the formation of a mixture of CoSi and Co germanides with higher resistivity due to the interfacial reaction and the accumulation of Ge at the interface, which may act as a diffusion barrier. The choice of a Si cap above SiGe, whose thickness was properly adjusted to the material consumption correlated with the resulting silicide thickness, is proposed.The process and the performance of SiGe HBTs could be improved by the introduction of a Ti salicide process: base resistances yield values around 20 Ω (for an emitter area of 0.8 5 μm 2 ). Nearly ideal Gummel plots confirm the advantage of using TiSi 2 .