Investigation of Ge1-xSnx/Ge with high Sn composition grown at low-temperature
I. S. Yu,
T. H. Wu,
K. Y. Wu,
H. H. Cheng,
V. I. Mashanov,
A. I. Nikiforov,
O. P. Pchelyakov,
X. S. Wu
Affiliations
I. S. Yu
Center for Condensed Matter Science and Graduate Institute of Electronics Engineering, 1, Roosevelt Road, Section 4, National Taiwan University, Taipei, Taiwan
T. H. Wu
Center for Condensed Matter Science and Graduate Institute of Electronics Engineering, 1, Roosevelt Road, Section 4, National Taiwan University, Taipei, Taiwan
K. Y. Wu
Center for Condensed Matter Science and Graduate Institute of Electronics Engineering, 1, Roosevelt Road, Section 4, National Taiwan University, Taipei, Taiwan
H. H. Cheng
Center for Condensed Matter Science and Graduate Institute of Electronics Engineering, 1, Roosevelt Road, Section 4, National Taiwan University, Taipei, Taiwan
V. I. Mashanov
A.V. Rzhanov Institute of Semiconductor Physics SB RAS, Lavrentyev Avenue, 13, Novosibirsk 630090, Russia
A. I. Nikiforov
A.V. Rzhanov Institute of Semiconductor Physics SB RAS, Lavrentyev Avenue, 13, Novosibirsk 630090, Russia
O. P. Pchelyakov
A.V. Rzhanov Institute of Semiconductor Physics SB RAS, Lavrentyev Avenue, 13, Novosibirsk 630090, Russia
X. S. Wu
Department of Physics, Nanjing University, Nanjing, China
We report on experimental investigations of the growth of Ge1-xSnx film with thickness above the critical thickness using Molecular Beam Epitaxy. A series of Ge1-xSnx films with various Sn compositions up to 14% are deposited on a Ge buffer layer for growth at low temperatures close to the melting point of Sn. Analysis of various measurements shows that the Ge1-xSnx film is defect free in the XTEM image and that Sn is distributed almost uniformly in the film for Sn compositions up to 9.3%. The Sn composition of the films is higher than the Sn composition that is theoretically predicted to cause the energy band of Ge to change from an indirect to a direct bandgap; thus, the present investigation provides a method for growing direct bandgap GeSn film, which is desired for use in applications involving optoelectronic devices.
