Atomic layer deposition of textured zinc nitride thin films

Abstract

Zinc nitride films are deposited by Atomic Layer Deposition (ALD) within a temperature range of 150–315 °C using diethylzinc (DEZ) and ammonia (NH₃). Self-limiting growth characteristics are examined by an in situ Quartz crystal microbalance (QCM) that is subsequently verified and complemented by ex situ X-ray reflectivity (XRR) measurements. A saturated growth rate of ca. 1.4 Å per ALD cycle is obtained within the ALD temperature window of 175–215 °C. In situ Fourier transform infrared (FTIR) spectroscopy is employed to study the reaction mechanism during each ALD half cycle. As deposited films on microscope glass substrates have strong orientation in the {321} direction. Films are found to be optically transparent with band-edge photoluminescence.