Chemical vapor transport (CVT) process with Br2 as a transporting agent has been utilized for growing large size MoSe2 single crystals by adding Re (rhenium) dopant (nominal concentration of 1%) during the growth process. The maximum size crystals are about 10 mm × 10 mm in surface area and 2 mm in thickness. The large edge plane facilitates easier study of the influence of crystal anisotropy on the electrical and optical properties of the layered crystals. The anisotropy of the conductivity and indirect band gap parallel and perpendicular to the crystal c-axis due to the interlayer van der Waals interaction and red shift of the indirect and direct band gaps due to doping have been measured. It is found that the conductivity anisotropy decreases drastically as a result of doping and the crystal anisotropy has a more pronounced influence on the indirect gap in comparing to the direct gap of the layered crystals.
關聯:
Journal of Alloys and Compounds, Vol.442 no.1-2, pp. 249-251
