Morphological evolution of thin AlN films grown by atomic layer deposition. Issue 1 (1st March 2022)

• Record Type: Journal Article
• Authors: Beshkova, M; Blagoev, B S; Mehandzhiev, V; Yakimova, R; Georgieva, B; Avramova, I; Terziyska, P; Strijkova, V
• Is Part Of: Journal of physics. Volume 2240:Issue 1(2022)
• Publication Date: 2022-03-01
• Subjects: Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/2240/1/012005
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract: Thin AlN films were grown using a Beneq TFS-200 ALD reactor. TMA (trimethylaluminium) and NH3 were used as precursors. The substrate temperature was 330 °C, the ALD cycles, 550. The TMA and NH3 doses (pulses) lasted 180 ms and 90 ms, followed by 2-s and 9-s nitrogen gas purge, respectively. In order to study the morphological evolution of the thin AlN films, substrates providing different surface kinetics were used: Si-face and C-face of 4°-off axis and on-axis 4H-SiC, and graphene grown on 4H-SiC by sublimation. As revealed by atomic force microscopy (AFM), the lowest RMS surface roughness of about 0.8 nm was exhibited by the AlN film deposited on Si-face on-axis 4H-SiC due to its higher surface energy which provides for better film nucleation. The chemical composition and bonding states were investigated by X-ray photoelectron spectroscopy (XPS). The existence of AlN is justified by the presence of the XPS peaks of Al 2p and N 1s at about 73.3 eV and 396.6 eV, respectively. These results are promising in view of further studies of thin AlN films properties for application in surface acoustic wave devices (SAW).