Method for fabricating a SONOS memory

A method for fabricating SONOS memory is disclosed. The method includes the steps of: providing a semiconductor substrate; forming a first silicon oxide layer, a silicon nitride layer, and a second silicon oxide layer on the surface of the semiconductor substrate; forming a hard mask on the second silicon oxide layer; patterning the hard mask, the second silicon oxide layer, the silicon nitride layer, and the first silicon oxide layer to form a patterned hard mask and a stacked structure; forming a gate oxide layer on surface of the patterned hard mask; removing the gate oxide layer and the patterned hard mask; forming a patterned polysilicon layer on surface of the stacked structure; and forming a source/drain region in the semiconductor substrate adjacent to two sides of the polysilicon layer.