Crystallization and memory programming characteristics of Ge-doped SbTe materials of varying Sb:Te ratio

Title
Crystallization and memory programming characteristics of Ge-doped SbTe materials of varying Sb:Te ratio
Authors
정증현이현석이수연이택성김원목우철김슬참오규환정병기
Keywords
phase change memory; Ge-doped SbTe; crystallization; nucleation rate; growth rate
Issue Date
2009-02
Publisher
Journal of physics D, applied physics
Citation
VOL 42, NO 3, 035104-1-035104-6
Abstract
A phase change memory (PCM) utilizes resistivity changes accompanying fast transitions from an amorphous to a crystalline phase (SET) and vice versa (RESET). An investigation was made on the SET characteristics of PCM cells with Ge-doped SbTe (Ge–ST) materials of two different Sb : Te ratios (4.53 and 2.08). For the material of higher Sb : Te (4.53), a SET operation was completed within several tens of nanoseconds via nucleation-free crystallization whereas the material of lower Sb : Te (2.08) rendered a slower SET operation requiring several hundred nanoseconds for a nucleation-mediated crystallization. From measurements of nucleation and growth kinetics via laser-induced crystallization, the observed SET characteristics of the former case were found to derive from a growth time about 103 times shorter than the nucleation time and those of the latter from a much shorter nucleation time as well as a longer growth time than in the former case. The measured nucleation kinetics of the lower Sb : Te (2.08) material is unexpected from the existing data, which has led us to advance an interesting finding that there occurs a trend-reversing change in the nucleation kinetics of the Ge-ST materials around the eutectic composition (Sb : Te ∼2.6); nucleation is accelerated with the increase in the Sb : Te ratio above Sb : Te of 2.6, but with a decrease in the Sb : Te ratio below it.
URI
http://pubs.kist.re.kr/handle/201004/34823
ISSN
0022-3727
Appears in Collections:
KIST Publication > Article
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE