Method of forming on a semiconductor substrate a capacitor electrode having hemispherical grains

摘要

An improved capacitor electrode made of polysilicon having a rough surface on a semiconductor substrate is formed by (a) removing a spontaneous oxidation film adhering to an amorphous silicon surface; (b) heating the amorphous silicon to a designated temperature; (c) spraying SiH4 at a designated temperature on the amorphous silicon to form an amorphous silicon/polysilicon mixed-phase active layer on the surface; (d) annealing at a designated temperature to form an HSG so as to roughen the amorphous silicon surface; (e) PH3-annealing the HSG-forming polysilicon, wherein PH3 is introduced at a designated concentration at the start of heating to a designated temperature; and (f) nitriding the amorphous silicon surface at the stated temperature by continuously introducing NH3 gas instead of PH3.