Abstract: The present invention provides an effective rapid thermal annealing process to fill a narrow contact window and to interconnect two conductive layers in semiconductor devices. The present invention rapidly raises an annealing temperature by a simple step of temperature raising under pure nitrogen after a step of depositing a contact layer and a barrier layer and before a step of filling a conductive layer in the contact window. Therefore, ammonia, which requires disposal treatment, is avoided and a good interconnection can be accomplished at a relative low temperature without damaging the conductive layers.