Structural Characterization of ZnTe Grown by Atomic-Layer-Deposition Regime on GaAs and GaSb (100) Oriented Substrates

Abstract

This work presents the characterization of ZnTe nanolayers grown on GaAs and GaSb (100) substrates by the Atomic Layer Deposition (ALD) regime. Under certain conditions, the alternating exposition of a substrate surface to the element vapours makes possible the growth of atomic layers in a reactor where the atmosphere is high-purity hydrogen. ZnTe was grown simultaneously on GaAs and GaSb at the same run, allowing, a comparison between the effects produced by the superficial processes due to the different used substrates, thereby eliminating possible unintended changes of growth parameters. Nanolayers on GaSb maintained their shiny appearance even at temperatures near 420°C. It was found that for exposure times below 2.5 s there was not growth on GaAs, while for GaSb the shortest time was 1.5 s at 385°C. By HRXRD the peak corresponding to (004) diffraction plane of ZnTe was identified and investigated, the FWHM resulted very wide (600-800 arcsec) indicating a highly distorted lattice mainly due to mosaicity. Raman scattering shows the peak corresponding to LO-ZnTe, which is weak and slightly shifted in comparison with the reported for the bulk ZnTe at 210 cm -1 . Additionally, the measurements suggest that the crystalline quality have a dependence with the growth temperature.

Remarkable Improvement of Thermoelectric Figure-of-Merit in SnTe through In Situ-Created Te Nanoinclusions

“…The presence of Te in the Sn 0.9 Te sample was also confirmed by a peak at a wave number of 269 cm −1 in the Raman spectroscopy data (shown in the Supporting Information S7). 18,19 Another observation from Figure 1b is that with increasing x (upto x = 1), there is a systematic shift of the (200) peak of SnTe toward higher 2θ value, which is attributed to the marginal enlargement of lattice parameters of SnTe, probably due to the strain induced in the SnTe matrix from solidification of excess Te. As per the PCPDF (008-0487) XRD record, pure SnTe exhibits 100% intensity for the (200) plane, but as seen from Figure 1a, in Sn 0.8 Te and Sn 0.95 Te samples, the highest peak intensity is for the (222) plane.…”

Microheater-Integrated Spectrally Selective Multiband Mid-Infrared Nanoemitter for On-Chip Optical Multigas Sensing

“…ALD offers precise control and uniformity in the film thickness and properties. Diethylzinc (DEZ) is a readily available precursor for ALD, and extensive research has been conducted on plasma-assisted ALD for tellurium deposition, as well as the use of alkylsilyl compounds as tellurium precursors for ALD. , Therefore, ALD stands as a strong candidate for achieving the desired high-quality deposition of 580 nm ZnTe . Following the deposition of ZnTe, a lithography and lift-off process can be employed to create an Al grating.…”

“…72,73 Therefore, ALD stands as a strong candidate for achieving the desired high-quality deposition of 580 nm ZnTe. 74 Following the deposition of ZnTe, a lithography and lift-off process can be employed to create an Al grating. This process involves applying a resist layer, followed by electron beam lithography (EBL) to transfer the grating pattern onto the resist, followed by developing.…”