Growth dynamics of reactive-sputtering-deposited AlN films

Abstract

͑ ͒We have studied the surface kinetic roughening of AlN films grown on Si͑100͒ substrates by dc reactive sputtering within the framework of the dynamic scaling theory. Films deposited under the same experimental conditions for different growth times were analyzed by atomic force microscopy and x-ray diffraction. The AlN films display a ͑002͒ preferred orientation. We have found two growth regimes with a crossover time of 36 min. In the first regime, the growth dynamics is unstable and the films present two types of textured domains, well textured and randomly oriented, respectively. In contrast, in the second regime the films are homogeneous and well textured, leading to a relative stabilization of the surface roughness characterized by a growth exponent ␤ = 0.37± 0.03. In this regime a superrough scaling behavior is found with the following exponents: ͑i͒ Global exponents: roughness exponent ␣ = 1.2± 0.2 and ␤ = 0.37± 0.03 and coarsening exponent 1/z = 0.32± 0.05; ͑ii͒ local exponents: ␣ loc =1, ␤ loc = 0.32± 0.01. The differences between the growth modes are found to be related to the different main growth mechanisms dominating their growth dynamics: sticking anisotropy and shadowing, respectively.

Universal non-equilibrium phenomena at submicrometric surfaces and interfaces

“…[49]. Actually, the type of scale invariance found frequently in these systems [50], known as anomalous scaling in this context, is not similar to equilibrium dynamic scaling [51], and remains to be understood from a fundamental point of view.…”

Dual growth modes in ion bombarded Si surfaces

“…These results are in complete agreement with the interface roughness data. Thus, the temporal evolution of the PSD curves does confirm the existence of two growth regimes for the morphology evolution of the eroded surfaces, with a cross over time close to about 35 minutes [6]. The growth is unstable till this time, after which there is a stable growth of the evolved surface.…”

Morphological features in aluminum nitride epilayers prepared by magnetron sputtering

“…Oxidized AlN can substitute traditional passivating films, such as silicon nitride and silicon oxide, at p-type solar cells [13], selective detectors [19], field emitters for flat panel displays, highspeed transistors [20]. As noted Auger et al [7], it can be applied as an intermediate buffer layer for optical and electronic devices and for further fabrication of heterostructures.…”

“…The studies of AlN thin film could be divided into the investigations which emphasize chemical and physical properties (mechanical, electrical, magnetic) [6,9,17,21,22], analysis of the films structure [4,7,12,15,16,19,[23][24][25]32] and combined, showing the dependences of the properties on the films morphology [2,11,13,14,26,[33][34][35]. The structure of the thin films can utterly differ from the structure of bulk material and have different structural perfection.…”