Method for fabricating polycrystalline silicon having micro roughness on the surface

Claim 1

A method of fabricating a semiconductor device having a capacitor, comprising the steps of: depositing an amorphous silicon layer (22) on a substrate (16,17,19,20); cleaning a surface of said amorphous silicon; annealing said amorphous silicon layer while keeping the surface of said amorphous silicon layer clean at a temperature above a transition temperature from an amorphous phase to a polycrystalline phase of silicon to thereby convert said amorphous silicon layer into a polycrystalline silicon layer, said polycrystalline silicon layer thereby having a micro-roughness surface caused by grains of silicon and serving as a first electrode of said capacitor; forming a dielectric film (23) of said capacitor on said micro-roughness surface of said polycrystalline silicon layer; and forming on said dielectric film a conductive layer (24) serving as a second electrode of said capacitor.