van Noord, K. (2017) Simulating scanning transmission electron microscopy images of GeTe-Sb2Te3 superlattice structures. Bachelor's Thesis, Applied Physics.
|
Text
Bachelor-Thesis-KvanNoord_1.pdf - Published Version Download (682kB) | Preview |
|
Text
Toestemming.pdf - Other Restricted to Backend only Download (81kB) |
Abstract
A new type of phase change materials based on Ge, Sb and Te is under large investigation for memory applications. This new nanostructured concept based on GeTe-Sb2Te3 superlattices shows better magnetic and electrical properties compared to their bulk counterparts. The research of Momand et al. in 2015 with high-angle annular dark field scanning transmission electron microscopy gave more information about the structure of the created GeSbTe blocks. However, the resulting images and intensity functions were not compared to theoretical calculations yet. In this work, the structure of these GeSbTe blocks is further examined using computer simulations. The annealed GeSb2Te4 tends to have a 65-30-90 composition on the sequential cation layers, where the annealed Ge2Sb2Te5 blocks shows signs of a symmetric 65-35 composition on the sequential cation layers. Furthermore, the results show that the computer simulations are not as accurate as initially thought due to approximations in the software. According to the simulations, the way of normalizing applied by Momand et al. is not recommended and a non-local normalization is preferred. Overall, the simulation software is a valuable method to give extra conclusions on the atomic layers in materials but a few improvements have to be made.
Item Type: | Thesis (Bachelor's Thesis) |
---|---|
Degree programme: | Applied Physics |
Thesis type: | Bachelor's Thesis |
Language: | English |
Date Deposited: | 15 Feb 2018 08:30 |
Last Modified: | 15 Feb 2018 08:30 |
URI: | https://fse.studenttheses.ub.rug.nl/id/eprint/15562 |
Actions (login required)
View Item |