Diffuse x-ray scattering from small defects in a very perfect silicon single crystal

Abstract

Two kinds of diffuse x-ray scattering were found in a very perfect silicon single crystal. One of them forms a cigar shape, extending along the [111] direction. The other is a disk shape whose normal is also parallel to the [111] direction in reciprocal space. Both diffuse scatterings are predominant along the crystal pulling [111] direction. From simple Fourier inversion of the shapes of the diffuse scatterings, it is concluded that the platelike defects and needlelike defects are the origins of the diffuse scatterings. The platelike defects observed differ from those observed by Patel for Czochralski silicon with heat treatment.

Microstructural and morphological properties of homoepitaxial (001)ZnTe layers investigated by x-ray diffuse scattering

“…As the growth above 360°C leads to Te-rich surface conditions, 23 this seems to favor the SF nucleation; indeed, a sensitivity of SF nucleation towards VI-group atoms has been already reported in the case of ZnSe epilayers grown by MOVPE on GaAs. 24 Furthermore, the HR-RSMs reported in Fig.…”

“…much lower than the hillock densities, estimated instead around 10 6 -10 7 cm -2 (Ref. 23). This rules out the possibility that substrate dislocations propagating into the epilayers could reach the surface and act as source for hillock formation.…”

“…23,25 In addition, XDS was also employed with success to study artificial periodic surface gratings 18 or laterally modulated structures. 19,20 In this paper we report on the XDS study of homoepitaxial ZnTe layers deposited by MOVPE on VGF-grown (100)ZnTe substrates.…”

“…The use of high-angle X-ray diffuse scattering (XDS) experiments has been often reported in the literature to reveal different kinds of lattice defects in heteroepitaxial structures, such as point defects, 15 , 16 dislocations, 17 -19 misfit dislocation at heterointerfaces, [20][21][22] stacking faults [23][24][25] and extended lattice defects. 23,25 In addition, XDS was also employed with success to study artificial periodic surface gratings 18 or laterally modulated structures.…”

“…3(b)], despite the XDS analysis in the previous Section confirmed the presence of SFs. However, we have shown elsewhere 23 that pyramidal hillocks develop under Te-rich surface conditions, the 3D growth around a SF partial dislocation being driven by Te ad-atoms experiencing a Schwoebel potential barrier at the step edges around the center. Instead, almost featureless surfaces are obtained under nearly equal (stoichiometric) Te and Zn adatom abundances, 31 such as those applying to the sample in Fig.3(b).…”