المؤلفون: Maruyama, Takahiro^1,2 takamaru@ccmfs.meijo-u.ac.jp, Matsuda, Keiji¹, Naritsuka, Shigeya^1,2

المصدر: Journal of Crystal Growth. Feb2005, Vol. 275 Issue 1/2, pe2155-e2160. 0p.

مصطلحات موضوعية: *CRYSTAL growth, *CRYSTALLIZATION, *ATOMIC force microscopy, *COLD (Temperature)

مستخلص: Abstract: Aiming at the fabrication of step-free Ge(111) surfaces of device size, liquid-phase epitaxy (LPE) growth was carried out on Ge(111) mesa structures. Reducing supersaturation by controlling the growth temperature, nearly atomically flat faces were formed on several mesas following LPE growth at less than 480°C. Taking into account the density of edge, screw and mixed dislocations, these flat faces appear to have formed on the top surface of screw and mixed dislocation-free mesas. Observation by atomic force microscopy (AFM) showed the presence of a number of triangular hollows with monolayer step depth on the flat faces, indicating “multinuclear layer-by-layer growth”. In addition, the number of triangular hollows was found to be exponentially dependent on the reciprocal of growth temperature. Taking into account the step velocity, the mechanism of two-dimensional nucleation on an atomically flat surface is discussed. [Copyright &y& Elsevier]

المؤلفون: Saitoh, Koji¹, Suzuki, Takashi¹, Maruyama, Takahiro^1,2 takamaru@ccmfs.meijo-u.ac.jp, Naritsuka, Shigeya^1,2

المصدر: Journal of Crystal Growth. Apr2005, Vol. 277 Issue 1-4, p51-56. 6p.

مصطلحات موضوعية: *EPITAXY, *OXIDES, *CRYSTAL growth, *TEMPERATURE

مستخلص: Abstract: Beam-induced lateral epitaxy (BILE), an epitaxial lateral growth method that does not require oxide masks, was done on prefabricated truncated ridges on a ()B GaAs substrate. We found that ()B facets formed on the top surface of the BILE layer and that the top layer was flatter than that grown on GaAs(001). BILE growth on an off-axis ()B substrate showed that the top surface became flatter with an increase of the off-axis angle. The flatness of the top surface also increased by increasing the growth temperature. These results indicate that the flatness of the top layer depends on the growth mode during BILE and that the suppression of two-dimensional nucleation of rotation twin embryo is important to fabricate a flat top layer using the BILE method. With the optimal growth conditions, we could make a flat surface of the BILE layer on GaAs()B surface. [Copyright &y& Elsevier]

المؤلفون: Tomita, Masafumi¹, Mizuno, Yosuke¹, Takakura, Hiroyuki¹, Kambayashi, Daisuke¹, Naritsuka, Shigeya¹ 133434022@ccalumni.meijo-u.ac.jp, Maruyama, Takahiro¹

المصدر: Journal of Crystal Growth. Apr2016, Vol. 440, p13-16. 4p.

مصطلحات موضوعية: *SUPERSATURATION, *GALLIUM arsenide, *MICROCHANNEL plates, *EPITAXY, *PROCESS optimization, *CRYSTALLOGRAPHY

مستخلص: Surface supersaturation in microchannel epitaxy (MCE) by liquid-phase epitaxy is a key parameter to control the width-to-thickness ratio (aspect ratio), which determines the dimensions of the dislocation-free area. The interstep distance of a spiral step at a screw-dislocation and curve-fitting of screw-like steps at stacking faults (SFs) are employed to estimate the surface supersaturation during MCE. The dependence of the vertical growth rate on the surface supersaturation was experimentally studied in GaAs(001) MCE. As a result, 2D nucleation at SFs was determined to act as a strong step source, which is stronger than a typical spiral step at a screw-dislocation over a wide range of surface supersaturation. Precise control of the surface supersaturation is important to optimize the growth conditions for MCE. An MCE layer with a large aspect ratio can thus be reproducibly obtained using appropriately controlled surface supersaturation. [ABSTRACT FROM AUTHOR]

المؤلفون: Naritsuka, Shigeya^1,2 narit@ccmfs.meijo-u.ac.jp, Matsuoka, Sota¹, Kondo, Toshiyuki¹, Saitoh, Koji¹, Suzuki, Takashi¹, Yamamoto, Yo², Maruyama, Takahiro^1,2

المصدر: Journal of Crystal Growth. Apr2007, Vol. 301-302, p42-46. 5p.

مصطلحات موضوعية: *GALLIUM arsenide, *EPITAXY, *SCANNING electron microscopes, *SURFACES (Technology)

مستخلص: Abstract: The formation mechanism of rotational twins was systematically studied in beam-induced lateral epitaxy (BILE) on (111)B GaAs substrates using in situ scanning electron microscope (SEM) and ex situ atomic force microscope (AFM). As a result, it was found that rotational twins were produced from two-dimensional nuclei on the surface with 2×2 reconstruction by introducing stacking faults beneath them. As-trimers on 2×2 reconstruction probably induced the change. This was confirmed by the result that the formation of rotational twins was suppressed by the use of substrates with offset angles and a high growth temperature. The former is characterized by the high density of surface steps, which inhibits two-dimensional nucleation by the narrow inter-step distance. The latter brings reconstruction, which includes no As-trimer, and leads to the normal stacking of growth with a smooth surface even with two-dimensional nucleation. [Copyright &y& Elsevier]