The effects of RF power on the interfacial property between Al₂O₃ and Si₃N₄ and on the memory property in a MANOS structure

The interface stability and memory properties of an Al 2 O 3 blocking oxide deposited using remote plasma atomic layer deposition (RPALD) at various RF powers were investigated. The plasma density increased with an increase in radio frequency (RF) power from 50 to 300 W due to increased neutral impact excitation rate. Based on x-ray photoelectron spectroscopy and auger electron spectroscopy, an oxygen-deficient interfacial layer was formed for Al 2 O 3 film deposition at 50 W. In addition, increased migrations of Si and N atoms were observed at low power due to the formation of fewer oxygen radicals. While reduced migrations of Si and N atoms from Si 3 N 4 to Al 2 O 3 were observed when the RF power was sufficient due to the sufficient oxygen radicals. Therefore, the interfacial reaction between Al 2 O 3 and Si 3 N 4 is dependent on the RF power. After applying 18 V, the program speed of Al 2 O 3 with 100 W, 200 W and 300 W were 10 −2 s, 10 −5 s and 10 −6 s, respectively.