Liquid Injection ALD of Pb(Zr,Ti)O[sub x] Thin Films by a Combination of Self-Regulating Component Oxide Processes

Abstract

Quaternary [PZT] films were deposited at by a combination of liquid injection atomic layer depositions (ALD) of binary PbO, , and thin films. We used water as the oxidant and two sets of precursors: , , and either or . These precursors were dissolved in ethylcyclohexane and separately injected into a vaporizer. The deposition rates of the metal elements were investigated as a function of the input of the solutions. We started the ALD–PZT process with . When the input of one solution was increased, the deposition rates of the metal elements continued to increase or fluctuate, showing a complex interdependence. A PZT film deposited on a three-dimensional (3D) structure had an inhomogeneous cation composition. The film uniformity on the 3D structure was significantly improved by substituting with . In this ALD–PZT process, self-regulated growths were confirmed for Pb and Zr. Although the deposition rate of Ti did not saturate due to a catalytic decomposition, this study suggests that the multilayer stacking ALD process is an effective method for building up homogeneous layers of multicomponent materials on desired 3D structures.