Microstructural and Electronic Properties of Rapid Thermally Grown MoS2|Silicon Hetero-Junctions with Various Process Parameters

Molybdenum disulphide (MoS 2 ) has gained tremendous attention due to its tunable semiconducting properties and versatile applications in future electronic and optoelectronic devices. Here, MoS 2 thin films were grown by adopting rapid thermal process. The process parameters like time and temperature have been systematically varied to modulate the morphological, microstructural, and electronic properties of MoS 2 thin films. A uniform morphology has been observed from FESEM images. The microstructural study was further carried out using XRD pattern and Raman spectra. The intensity of (002) XRD characteristic peak at 2θ = 14.1° is found to be increased, whereas the FWHM values are reduced with the growth time and process temperature. The improvement of crystallinity of the MoS 2 thin films with growth temperature is attributed to the decrease in the FWHM values of the characteristic Raman peaks, and A 1 g . The dependence of hetero-junction characteristics such as ideality factor η, built-in voltage V bi , and carrier concentration on the growth parameters was evaluated using current-voltage and capacitance–voltage measurements. The films grown at 900°C for 5 min have possessed carrier concentration of 5.21 × 10 16 cm –3 , with 0.55 V as V bi , and η is found to be 2.04 for MoS 2 |Si hetero-junction. The decrease in the carrier concentration, η, and V bi in MoS 2 |Si hetero-junction with the increase in the growth temperature has been ascribed to the reduction in the defect states due to enhancement in the sulfurization.