Barrier Characteristics of ZrN Films Deposited by Remote Plasma-Enhanced Atomic Layer Deposition Using Tetrakis(diethylamino)zirconium Precursor

摘要

The barrier characteristics of ZrN films deposited by remote plasma-enhanced atomic layer deposition (PEALD) using Zr[NEt_2]_4 [tetrakis(diethylamino)zirconium, TDEAZ] and N_2 remote plasma have been investigated using various deposition parameters, such as temperature, plasma power, and processing pressure. The optimized processing temperature, plasma power, and pressure were 300℃, 200 W, and 1 Torr, respectively. ZrN films deposited by remote PEALD using TDEAZ and N2 remote plasma showed a carbon content of about 6 at. %. The resistivity of ZrN films was about 400 μΩ·cm. The barrier characteristics of Cu/ZrN/Si samples have been investigated by X-ray diffraction (XRD) analysis, Auger electron spectroscopy (AES), and etch-pit test after annealing in vacuum for 1h in the temperature range of 500-700℃ with an interval of 50℃. The structure of ZrN films remained amorphous up to 550℃ and crystallized after annealing above 600℃. The barrier characteristics of ZrN films remained up to 550℃. ZrN films deposited by remote PEALD are believed to be applicable as barriers for Cu metallization in a semiconductor process.