Structural inheritance from polycrystalline underlayers in the growth of double-layered aluminum films

Experimental evidence of the inherited strong <111≳ orientation from the room-temperature- evaporated Al underlayer is presented for the Al upperlayers evaporated at temperatures higher than the Al recrystallization temperature, in the double-layered Al films. By contrast, Al films evaporated on an amorphous SiO2 substrate at high temperatures exhibit a remarkable weakening of the <111≳ fiber texture. Crystallographic characteristics of the Al films were evaluated by rocking curves in the x-ray diffraction measurement. Inheritance of the strong preferential orientation observed for the double-layered structures suggests that the Al upper- layers grow in a layer-by-layer process during the deposition at high temperatures through the surface migration of Al atoms.