Sulfurization-induced growth of single-crystalline high-mobility β-In2S3 films on InP

Abstract

Metalorganic chemical vapor deposition was used to grow single-crystalline tetragonal β-In2S3 films on InP to afford covalently bonded In2S3/InP heterostructures, with the crystal structure of these films identified by high-resolution scanning transmission electron microscopy, X-ray diffraction, and Raman spectroscopy analyses, and the corresponding bandgap energies determined by photoluminescence measurements at room (300 K) and low temperatures (40 K). RT-PL measurements reveal the three peaks spectral emission at 464.3, 574.7, and 648.5 nm associated with luminescence from band-edge and two above conduction band-edge, respectively, although the LT-PL (40K) measurements of β-In2S3 film found two dominant peaks. Moreover, the above films exhibited n-type conductivity, with background electron concentration = 4.9 × 1015 cm-3, electron mobility = 1810.9 cm2 V-1 s-1, and resistivity = 0.704 Ω cm. Thus, single-crystalline β-In2S3 films deposited on InP are promising constituents of high-performance next-generation electronic, optoelectronic, and photovoltaic devices.