Surface Roughing Research Articles

Morphology evolution during strained (In,Ga)As epitaxial growth on GaAs vicinal (100) surfaces

Molecular-beam-epitaxy growth of strained (In,Ga)As on GaAs vicinal (100) surfaces is investigated by scanning tunneling microscopy. Surface roughing as the consequence of step bunching driven by strain is explored. By tuning the In content over the range from 0.05 to 0.2, the step bunching is observed to exhibit considerable uniformity and order. These results experimentally demonstrate that strain-driven step bunching is a viable approach to provide templates for nanostructure growth.

Carrier Profiling and Crystal Quality Evaluation of Thin AlxGa1 − xAs ( 0.22 < x < 0.86 ) Films by Electrochemical Capacitance/Voltage Technique

We have applied an electrochemical capacitance/voltage method to determine doping profiles and material quality of -type heterostructures with ranging from 0.24 to 0.86 in a single measurement step. It was found that the etching rate of the high content Al samples is low and the resulting surfaces are rough, independent of the etchant used. Though surface roughing is associated with an inherent property of the doping depth profile can be determined in an accurate way. On the basis of secondary ion mass spectroscopy, Hall effect, and electrochemical capacitance/voltage measurements the total donor concentration could be estimated. © 2003 The Electrochemical Society. All rights reserved.

Microstructure and Surface Evolution in the Crystallization of α-Fe2O3/α-Al2O3(0001) Thin Films

ABSTRACTWe found the correlation between microstructure and surface evolution in the crystallization of amorphous α-Fe2O3/α-Al2O3(0001) thin films using real-time synchrotron x-ray scattering and atomic force microscope. The amorphous precursor is crystallized to the epitaxial α-Fe2O3 grains in three steps; i) the growth of the well aligned α-Fe2O3 interfacial islands on α-Al2O3(0001), ii) the growth of the misaligned, homoepitaxial, α-Fe2O3 grains on the well aligned grains ( &gt; 400 °C), and iii) the nucleation of the heteroepitaxial misaligned grains directly on the α-Al2O3substrate ( &gt; 600 °C). The surface roughing is caused by the microstructure evolution during the crystallization of the amorphous precursor films.

A Reflectometric Study of the Reaction between Si and WF 6 during W‐LPCVD on Si and of the Renucleation during the H 2 Reduction of WF 6

The formation of W through the reduction of by Si is monitored in situ using a wavelength adjustable reflectometer. The reflectance‐time relation can be understood and modeled by assuming island growth and a statistical distribution of the island thickness. The model is supported by SEM and Auger observations. The effect of surface layers like native oxides or a plasma treatment on the inhomogeneous Si consumption by the reaction between Si and (gouging) and its effect on the reflectance‐time relation are understood. The model is also applicable in the case of renucleation during the reduction of . A renucleation step consists of the deposition of Si from followed by the Si consumption by. A renucleation step reduces the surface roughing which occurs during the reduction process.