Mechanistic study of atomic layer deposition of Al{sub x}Si{sub y}O thin film via in-situ FTIR spectroscopy
A study of surface reaction mechanism on atomic layer deposition (ALD) of aluminum silicate (Al{sub x}Si{sub y}O) was conducted with trimethylaluminum (TMA) and tetraethoxysilane (TEOS) as precursors and H{sub 2}O as the oxidant. In-situ Fourier transform infrared spectroscopy (FTIR) was utilized to elucidate the underlying surface mechanism that enables the deposition of Al{sub x}Si{sub y}O by ALD. In-situ FTIR study revealed that ineffective hydroxylation of the surface ethoxy (–OCH{sub 2}CH{sub 3}) groups prohibits ALD of SiO{sub 2} by TEOS/H{sub 2}O. In contrast, effective desorption of the surface ethoxy group was observed in TEOS/H{sub 2}O/TMA/H{sub 2}O chemistry. The presence of Al-OH* group in vicinity of partially hydroxylated ethoxy (–OCH{sub 2}CH{sub 3}) group was found to propagate disproportionation reaction, which results in ALD of Al{sub x}Si{sub y}O. The maximum thickness from incorporation of SiO{sub x} from alternating exposures of TEOS/H{sub 2}O chemistry in Al{sub x}Si{sub y}O was found to be ∼2 Å, confirmed by high resolution transmission electron microscopy measurements.
- OSTI ID:
- 22479654
- Journal Information:
- Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films, Vol. 33, Issue 5; Other Information: (c) 2015 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0734-2101
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
42 ENGINEERING
ALUMINIUM SILICATES
CHEMICAL REACTION KINETICS
DEPOSITION
DESORPTION
FOURIER TRANSFORM SPECTROMETERS
FOURIER TRANSFORMATION
HYDROXYLATION
INFRARED SPECTRA
OXIDATION
SILICON OXIDES
SPECTROSCOPY
SURFACES
THICKNESS
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY
WATER