Journal
Scientific and Technical Journal of Information Technologies, Mechanics and Optics
UDK539.211, 538.971
Issue:5 (135)
Download PDF0 Kbyte
Abnormal diffusion profile of adatoms on extremely wide terraces of the Si(111) surface
Annotation
The authors experimentally studied the distribution of the adatom concentration on extremely wide terraces of the Si(111) surface whose dimensions are comparable with the diffusion length of adatoms. The extremely wide terraces were created during in situ experiments carried out by ultrahigh vacuum reflection electron microscopy by high-temperature annealing of Si(111) samples (more than 1000 °C) followed by rapid cooling to 750 °C to form 7 × 7 superstructure domains. A detailed analysis of the surface morphology of the terraces was carried out by ex situ atomic force microscopy under ambient conditions. Based on high-resolution (1.2 nm/pixel) atomic force microscopy images, panoramic topographic images of the terraces were formed. Digital processing of the panoramic images visualized the distribution of the adatom concentration n. For a terrace cooled from 1070 °C, central terrace regions show minimum n values around 0.13 BL (1 bilayer (BL) = 1.56×1015 cm−2); close to the monatomic step bordering the terrace, n increases to about 0.14 BL. The authors determined that this radial distribution n(r) at 1070 °C corresponds to the adatom diffusion coefficient D = 59 ± 12 μm2/s. It was found that, for a terrace cooled from 1090 °C, the approach assuming the same adatom diffusion length over the entire terrace does not describe the experimental n(r) distribution. For its analysis, the authors used the solution of the stationary diffusion equation under the assumption that D is not constant. Based on a numerical solution, the dependence of D on the experimentally measured n values was obtained. Under the assumption that adatom lifetime does not depend on n at 1090 °C, the adatom diffusion coefficient was found to decrease from 140 μm2/s at n = 0.093 BL (in the central terrace regions) to 5 μm2/s at n = 0.118 BL (near the step). The results of this work experimentally demonstrated that the control over adatom concentration can be used to significantly vary the diffusion properties of the adsorption layer on the crystal surface.
Keywords
Постоянный URL
Articles in current issue
- Features of images of water, ice, snow, objects and a human formed by a hybrid television camera in the near-infrared range
- Analyzing periodical textured silicon solar cells by the TCAD modeling
- Scintillation gamma radiation sensors based on solid-state photomultipliers in wireless industrial internet networks
- Improving the quality of network management of technological processes
- Geometric approach to the solution of the Dubins car problem in the formation of program trajectories
- Drift of two-dimensional vacancy islands on the Si(100) surface under electromigration conditions
- A study of the photocatalytic properties of chitosan-TiO2 composites for pyrene decomposition
- Kinetics of transformation of the atomic step bunches shape under electromigration conditions on the Si(001) surface
- An experimental methodology for assessing the probability and danger of network attacks in automated systems
- A meta-feature selection method based on the Auto-sklearn framework
- Automatic construction of the dialog tree based on unmarked text corpora in Russian
- Generic programming with combinators and objects
- Machine learning of the Bayesian belief network as a tool for evaluating the process frequency on social network data
- Software restructuring models for object oriented programming languages using the fuzzy based clustering algorithm
- The concept of managing the network structure of intelligent devices in the digital transformation of the energy industry
- Protecting facial images from recognition on social media: solution methods and their perspective
- Redundant models of testable distributed real-time computing systems
- A study of the influence of the base thickness on photoelectric parameters of silicon solar cells with the new TCAD algorithms
- A balanced algorithm of the hybrid large-particle method and its verification on some test problems
- The architecture of a system for full-text search by speech data based on a global search index
- Assessment of cerebral circulation through an intact skull using imaging photoplethysmography