The Effects of Radio Frequency Plasma Power on Al2O3 Films Deposited at Room-Temperature by Remote Plasma Atomic Layer Deposition

Abstract

Al2O3 films were deposited by a remote plasma atomic layer deposition (RPALD) method at room temperature (25 degrees C) in a reactor using alternating exposures of Al(CH3)3 and O2 plasma. Oxygen plasma was used as a reactant gas to decompose the trimethylaluminum [TMA, Al(CH3)3] precursor at room temperature. The RF plasma power was increased to produce enough radicals for the deposition of the Al2O3 films at room temperature. Then, changes in the interfacial and bulk properties of the deposited Al2O3 films were investigated according to increasing RF power. Al2O3 films deposited by RPALD with RF powers over 100 W showed similar bulk properties, indicating that radicals over a certain threshold did not have a decisive effect on the additional decomposition of precursors for a low impurity content in the films. An increase in RF plasma power could improve the interfacial stability due to an increase in radicals and ions in the plasma and the minimization of plasma-induced substrate damage by adopting remote plasma.