Abstract: In a method of manufacturing a semiconductor device, a step (d) of forming metal silicide films (20) on source and drain regions (17, 18) and on gate electrodes (71, 81) comprises selectively depositing silicon thin films (19) on the source and drain regions and the gate electrodes, the silicon thin films having impurity concentration less than 10.sup.19 cm.sup.-3 ; amorphizing the silicon thin films, the gate electrodes, and a silicon semiconductor substrate (11) by ion implantation; depositing a metal film on the silicon thin films, on the gate electrodes, and on the silicon semiconductor substrate; performing heat treatment of the metal film to form the metal silicide films (20) on the source and drain regions and the gate electrodes; and removing unreacted metal films (21) remaining on insulating films (16-1, 16-2). Preferably, the selectively depositing step may be performed by a chemical vapor deposition process of a reaction rate-determining mode by using disilane gas or silane gas.