Memory: Leti researchers observe GST
Categorie(s) : MINATEC, News, Research
Published : 4 February 2013
Germanium-Antimony-Tellurium, or GST, is a phase-change material that passes from an amorphous to a crystalline state at temperatures of 100°C to 150°C, making it a good candidate for phase-change memory. However, when looking at GST samples under a transmission microscope, scientists observed that these properties actually turn into a disadvantage. During the ion-beam preparation phase, the sample gets so hot that it crystallizes, creating a crippling artefact.
A Leti research team worked around this hurdle by reducing the ion beam’s output from 30 kV to 8 kV. The preparation phase is less accurate and twice as long at this lower power, but the thin (100 nm) film obtained is uniformly amorphous. The technique must now be fine-tuned to shorten preparation time and make it suitable for entire films.