Atomic Layer Deposited Al2O3 Film on Si 100 as Buffer Layer for HfxTi1-xO2 Deposition

Abstract

Ultra-thin films of Al 2 O 3  were deposited on Si(100) by atomic layer deposition (ALD) using tris(diethylamino)aluminium (TDEAA) with water vapor as the oxidizer. It is planned to deposit nano-laminated composite films of Hf x Ti 1-x O 2  on top of this ultra-thin Al 2 O 3  buffer layer using tetrakis(diethylamino)titanium (TDEAT) and tetrakis(diethylamino)hafnium (TDEAH). The introduction of the Al 2 O 3  buffer layer will improve the interfacial quality and help to retain amorphous structure of Hf x Ti 1-x O 2 /Al 2 O 3 /Si. Discussion of the addition of the new precursor, TDEAA, to the existing ALD system is discussed along with the optimization of process parameters for ALD of Al 2 O 3  films. An Al 2 O 3  film growth rate of 1 cycle was achieved in the ALD temperature window of 200-275 o  C.