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

Abstract

Ultra-thin films of Al2O3 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 HfxTi1-xO2 on top of this ultra-thin Al2O3 buffer layer using tetrakis(diethylamino)titanium (TDEAT) and tetrakis(diethylamino)hafnium (TDEAH). The introduction of the Al2O3 buffer layer will improve the interfacial quality and help to retain amorphous structure of HfxTi1-xO2/Al2O3/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 Al2O3 films. An Al2O3 film growth rate of 1 cycle was achieved in the ALD temperature window of 200-275o C.