Crystallization behavior of thin ALD-Al2O3 films

ALD Functionalized Nanoporous Gold: Thermal Stability, Mechanical Properties, and Catalytic Activity

“…Interestingly, the breakdown of the stabilizing effect of the Al 2 O 3 coating coincides with the crystallization temperature of the initially amorphous Al 2 O 3 film. 32,33 In one instance, we found several empty alumina 'shells' in a sample that was annealed at 600 o C. This finding demonstrates two important points: (1) even few-nm-thick ALD alumina films are continuous, and (2) defects in the alumina coating drastically reduce the thermal stability. The thickness of the alumina films, on the other hand, does not seem to have a pronounced effect on the thermal stability, and even samples that were coated with sub-nm-thick alumina films (2 ALD cycles) were stable up to at least 900…”

“…• C. 32,33 In an attempt to better understand the effect of ALD coatings on the mechanical behavior of np-Au, we first applied the core-shell model developed by Liu et al 44 to estimate the mechanical behavior of the Al 2 O 3 -coated gold ligaments, and then used these values as an input to the Gibson-Ashby (G-A) scaling equations 45 that correlate the properties of the individual ligaments with the bulk mechanical response of np-Au as measured by nanoindentation experiments. where   / s is the relative density of the material (0.3 in the present study).…”

Interfacial studies of Al2O3 deposited on 4H‐SiC(0001)

“…As compared to the Si/SiO 2 interface, the density of interface states (D it ) at the SiC/SiO 2 interface is at least one or two orders of magnitude higher (∼10 12 eV −1 cm −2 ). [1] Two dominant sources of electrically active defects have been suggested; C clusters and the so-called near-interface traps (NITs).…”

“…[10] However, good thermal stability and low-leakage currents for Al 2 O 3 devices have been achieved also after crystallization of the Al 2 O 3 layer at 1273 K. [11] Further annealing, at the crystallization temperature and above, increases the dielectric constant of the Al 2 O 3 films (ε ∼ 11-14). [12] Recent results by Hino et al [13] for 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFET) with Al 2 O 3 as gate dielectric, yield a peak fieldeffect mobility of 78 ± 10 cm 2 /Vs which, although promising, is substantially below that of ∼150 cm 2 /Vs for state of the art 4H-SiC MOSFETs with SiO 2 as gate dielectrics. In this work we used XPS, TEM, and SIMS to investigate the effect of annealing on the nature of the Al 2 O 3 /SiC interface.…”

Selective-area growth and magnetic characterization of MnAs/AlGaAs nanoclusters on insulating Al2O3 layers crystallized on Si(111) substrates

“…26 It was also reported that amorphous Al 2 O 3 layers prepared by ALD crystallized after an annealing treatment at a relatively high temperature. [27][28][29] 30,31 Being able to electrically isolate the NCs grown by SA-MOVPE from the underlying semiconducting layers comprises an important step towards making FM III-V hybrids promising candidates for a use in spintronics. Such NCs can be used as building blocks for future spintronic devices, such as magnetic logics, memories, and sensors, that will be fabricated on semiconducting substrates in a reproducible manner, as discussed in our review paper.…”