Patent ID: 6964900

Claim:
A method for fabricating a capacitor in a semiconductor device having a dual dielectric film structure, the method comprising the steps of: forming a lower electrode on a semiconductor substrate; forming a dielectric film with a dual dielectric film structure composed of an Si 3 N 4 chloride-free thin film and a Ta 2 O 5 thin film on the lower electrode; forming an upper electrode on the dielectric film, wherein SiH 2 [NH (C 4 H 9 )] 2 ; BTBAS[bis(tertiary-butylamino-silane)] in liquid state is used as silicon nitride source, when the Si 3 N 4 chloride-free thin film is deposited; and wherein a source gas for the Si 3 N 4 chloride free thin film is obtained by vaporization of proper amounts of BTBAS solution at a temperature range of 166 to 200° C., which is supplied to an evaporizer or an evaporation tube by means of a flow controller such as a liquid mass flow controller (LMFC).