Structural defects in ZnGeP₂single crystals revealed by X-ray topography

Abstract

The results of X-ray transmission topography and diffraction analysis of a ZnGeP 2 single crystal grown by the vertical Bridgman method in the [001] direction are presented and discussed. The FWHM of rocking curves over a large area of a (100) longitudinal slice is about 12 00 , which is indicative of the high quality of the examined sample. Glow discharge mass spectrometry does not show significant content of foreign chemical elements. X-ray topography reveals growth striations and dislocations. The predominant defects are single dislocations and their pile-ups. Near to the growth-axis region, curved dislocation bundles passing through the entire crystal are observed, on which precipitates are formed. In the initial part of the crystal, dislocations are located chaotically, while towards the middle of the sample they are aligned along the growth striae. In the final part of the crystal, the dislocation density increases.

Low-angle boundaries in ZnGeP2single crystals

“…The slight lattice rotation of one sub-grain, relative to another, negatively influences optical device performance. Such low-angle boundaries were revealed in our recent study (Lei et al, 2018).…”

“…The lattice misorientation arising from the symmetrical tilt boundaries studied here should be at its maximum value when the rotation axis [001] of tilt between subgrains is perpendicular to the diffraction plane. Such a condition was realized in the work of Lei et al (2018) with use of the 040 reflection from a ZnGeP 2 sample cut along the (100) plane. Using this method, the orientation contrast was revealed from subgrains on the topograph.…”

Mechanochromic Wide-Spectrum Luminescence Based on a Monoboron Complex

“…Meanwhile, the widths at the half-maximums of the curves are 0.144, 0.149, and 0.152°. These facts demonstrate the good phase purity of the bulk crystals as grown. − This is further supported by the pure fluorescence color of the respective bulk samples of the crystals under study. As described above, different phases of the B-1 crystals show highly unique fluorescent colors.…”

Методы Рентгеновской Дифракционной Топографии (О Б З О Р)

“…Метод Ланга особенно эффективен при изучении структурных дефектов в слабопоглощающих РЛ кристаллах. Он получил широкое распространение при характеризации реальной структуры монокристаллических пластин кремния, используемых в электронной промышленности для производства полупроводниковых микросхем (например, [41,[50][51][52] [56,57].…”