Open AccessMorphological evolution of thin AlN films grown by atomic layer deposition
Author(s) -
Milena Beshkova,
B. Blagoev,
V. Mehandzhiev,
Rositza Yakimova,
Borislava Georgieva,
I. Avramova,
Penka Terziyska,
Velichka Strijkova
Publication year - 2022
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2240/1/012005
Subject(s) - x ray photoelectron spectroscopy , sublimation (psychology) , materials science , thin film , atomic layer deposition , nucleation , substrate (aquarium) , analytical chemistry (journal) , surface roughness , chemical vapor deposition , layer (electronics) , sapphire , chemical engineering , nanotechnology , composite material , chemistry , optics , psychology , laser , oceanography , physics , organic chemistry , chromatography , geology , engineering , psychotherapist
Thin AlN films were grown using a Beneq TFS-200 ALD reactor. TMA (trimethylaluminium) and NH 3 were used as precursors. The substrate temperature was 330 °C, the ALD cycles, 550. The TMA and NH 3 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).