Speaker
Mr
Phuti Balty Tjale
(School of Physics, University of the Witwatersrand, Private Bag 3, 2050 WITS)
Description
Intensive interest on Ge-Sb-Te (GST) based alloys is driven by their outstanding electrical and optical properties which makes them excellent candidates for universal nonvolatile memory applications, also known as the phase change random access memory (PCRAM). The operating principle of the PCM is based on the rapid iterative reversible transition between two structural phases after a threshold voltage. However, their thermal conductivity is critical to device performance since it determines the resistance drift during the cyclic joule heating of the sandwiched active layer. Very few studies have been reported on the elastic and thermal properties of ternary alloys formed from GeTe and Sb2Te3 building blocks. In this work, thin films of Sb2Te3 and Ge1Sb4Te7 deposited by RF magnetron are investigated to establish the dependence of acoustic hardening on Sb2Te3 rich phase change alloy. Using the measured elastic properties and acoustic phonon velocities, the dependence of thermal conductivity on the Sb2Te3 fraction in Ge1Sb4Te7 by surface Brillouin scattering based on the minimum conductivity model is established.
Apply to be<br> considered for a student <br> award (Yes / No)?
Yes
Level for award<br> (Hons, MSc, <br> PhD, N/A)?
MSc
Primary author
Mr
Phuti Balty Tjale
(School of Physics, University of the Witwatersrand, Private Bag 3, 2050 WITS)
Co-authors
Dr
Bhekumusa Mathe
(University of the Witwatersrand)
Dr
Daniel Wamwangi
(wits university)
Prof.
David Billing
(University of the Witwatersrand)
Ms
Mmapula Baloi
(University of the Witwatersrand)
Mr
eric njoroge
(university of pretoria)
