Band Engineering by Controlling vdW Epitaxy Growth Mode in 2D Gallium Chalcogenides.
Atomically thin quasi-2D GaSe flakes are synthesized via van der Waals (vdW) epitaxy on a polar Si (111) surface. The bandgap is continuously tuned from its commonly accepted value at 620 down to the 700 nm range, only attained previously by alloying Te into GaSe (GaSex Te1- x ). This is accomplished by manipulating various vdW epitaxy kinetic factors, which allows the choice bet ween screw-dislocation-driven and layer-bylayer growth, and the design of different morphologies with different material-substrate interaction (strain) energies.
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, 85287, USA.
Hui
H
Cai
LeRoy Eyring Center for Solid State Science, Arizona State University, Tempe, AZ, 85287, USA.
Emmanuel
E
Soignard
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
Can
C
Ataca
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, 85287, USA.
Bin
B
Chen
Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA.
Changhyun
C
Ko
LeRoy Eyring Center for Solid State Science, Arizona State University, Tempe, AZ, 85287, USA.
Toshihiro
T
Aoki
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, 85287, USA.
Anupum
A
Pant
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, 85287, USA.
Xiuqing
X
Meng
School of Materials Science and Engineering, Beihang University, Beijing, 100191, P. R. China.
Shengxue
S
Yang
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
Jeffrey
J
Grossman
Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, 94720, USA.|Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
Frank D
FD
Ogletree
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, 85287, USA. sefaattin.tongay@asu.edu.
Sefaattin
S
Tongay
2D materials; band engineering; van der Waals epitaxy