Moisture Barrier Properties of Al2O3 Films deposited by Remote Plasma Atomic Layer Deposition at Low Temperatures

Abstract

We report the effect of process temperature on moisture permeation barrier properties of Al2O3 films deposited by remote plasma atomic layer deposition (RPALD) at various low temperatures from 50 to 200 °C. XPS analysis of O 1s peak reveals that the O-H ratio decreases with process temperature from 38.1% at 50 °C to 25.8% at 200 °C. The water transmission rates using electrical Ca degradation test indicates that the 100nm Al2O3 film enhances the moisture barrier performance from 2.0 × 10-2 to 5.0 × 10-4 gm-2 day-1 with increasing the process temperature. This result indicates that increasing the process temperature improves the moisture permeation barrier properties significantly even in RPALD process. It is attributed to the increase in the Al2O3 mass density due to the decrease of relatively O-H ratio with increase in temperature as revealed by XPS O 1s peak deconvolution and FTIR analysis in the Al2O3 films.