Evaluation of Strain-Relaxation of Carbon-Doped Silicon Nanowires and Its Crystal Orientation Dependence Using X-Ray Diffraction Reciprocal Space Mapping

Strain distributions in carbon-doped silicon nanowires along [110] and [100] investigated by X-ray diffraction

“…These C-doped Si films were deposited on Si (001) substrates by MBE. 34) The length of the long side of each sample was kept constant at 10 μm, and the width of the short side was 1000, 500 or 200 nm. These nanowires were patterned with periodicities of 5 μm and 15 μm in the shortand long-side directions in square areas of 1.5 mm × 1.5 mm.…”

“…These nanowires were patterned with periodicities of 5 μm and 15 μm in the shortand long-side directions in square areas of 1.5 mm × 1.5 mm. [32][33][34] As-deposited areas of C-doped Si thin films were retained as references.…”

“…5,6,18,22) These methods give excellent results with very fine spatial resolution but are not suitable for statistical investigations since local and individual characteristics are emphasized By observing samples with many nanowires periodically arranged within a 1.5 mm × 1.5 mm region with X-rays of sub-millimeter beam width, we obtained statistically averaged characteristics while eliminating the effects of individual nanowire differences, as previously reported. [32][33][34] Previously, we found an indication that [100] nanowires were more relaxed than [110] nanowires by assuming that all nanowires have uniform lattice spacings. 34) However, differences between [100] and [110] C-doped Si nanowires were very ambiguous, since spreading RSM profiles in the observations indicate quite large distributions of lattice spacings.…”

“…[32][33][34] Previously, we found an indication that [100] nanowires were more relaxed than [110] nanowires by assuming that all nanowires have uniform lattice spacings. 34) However, differences between [100] and [110] C-doped Si nanowires were very ambiguous, since spreading RSM profiles in the observations indicate quite large distributions of lattice spacings. 34) Recently, we clarified quantitatively that residual strains in C-doped Si nanowires along [100] are smaller than those of [110] nanowires following detailed investigation on the observed RSM profiles by considering the distribution of lattice spacings.…”

“…34) However, differences between [100] and [110] C-doped Si nanowires were very ambiguous, since spreading RSM profiles in the observations indicate quite large distributions of lattice spacings. 34) Recently, we clarified quantitatively that residual strains in C-doped Si nanowires along [100] are smaller than those of [110] nanowires following detailed investigation on the observed RSM profiles by considering the distribution of lattice spacings. It was also shown that the effect of crystal orientation of nanowires on lattice relaxation increases with increasing lattice mismatch between nanowires and substrates.…”