A ferroelectric oxide made directly on silicon.
Metal oxide semiconductor field-effect transistors, formed using silicon dioxide and silicon, have undergone four decades of staggering technological advancement. With fundamental limits to this technology close at hand, alternatives to silicon dioxide are being pursued to enable new functionality and device architectures. We achieved ferroelectric functionality in intimate contact with silicon by growing coherently strained strontium titanate (SrTiO3) films via oxide molecular beam epitaxy in direct contact with silicon, with no interfacial silicon dioxide. We observed ferroelectricity in these ultrathin SrTiO3 layers by means of piezoresponse force microscopy. Stable ferroelectric nanodomains created in SrTiO3 were observed at temperatures as high as 400 kelvin.
Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA.
Maitri P
MP
Warusawithana
Cheng
C
Cen
Charles R
CR
Sleasman
Joseph C
JC
Woicik
Yulan
Y
Li
Lena Fitting
LF
Kourkoutis
Jeffrey A
JA
Klug
Hao
H
Li
Philip
P
Ryan
Li-Peng
LP
Wang
Michael
M
Bedzyk
David A
DA
Muller
Long-Qing
LQ
Chen
Jeremy
J
Levy
Darrell G
DG
Schlom