Metastable Ge1-xCx alloy nanowires.
Carbon-containing alloy materials such as Ge(1-x)C(x) are attractive candidates for replacing silicon (Si) in the semiconductor industry. The addition of carbon to diamond lattice not only allows control over the lattice dimensions, but also enhances the electrical properties by enabling variations in strain and compositions. However, extremely low carbon solubility in bulk germanium (Ge) and thermodynamically unfavorable Ge-C bond have hampered the production of crystalline Ge(1-x)C(x) alloy materials in an equilibrium growth system. Here we successfully synthesized high-quality Ge(1-x)C(x) alloy nanowires (NWs) by a nonequilibrium vapor-liquid-solid (VLS) method. The carbon incorporation was controlled by NW growth conditions and the position of carbon atoms in the Ge matrix (at substitutional or interstitial sites) was determined by the carbon concentration. Furthermore, the shrinking of lattice spacing caused by substitutional carbon offered the promising possibility of band gap engineering for photovoltaic and optoelectronic applications.
Skku Advanced Institute of Nanotechnology, School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 440-746, Korea.
Byung-Sung
BS
Kim
Jae-Hyun
JH
Lee
Kiseok
K
Son
Sung Woo
SW
Hwang
Byoung Lyong
BL
Choi
Eun Kyung
EK
Lee
Jong Min
JM
Kim
Dongmok
D
Whang
D000497:Alloys; D002244:Carbon / Q000737:chemistry*; D003460:Crystallization; D005857:Germanium / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D012666:Semiconductors; D012825:Silicon / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics
D000497:Alloys; D005857:Germanium; D002244:Carbon; D012825:Silicon