Cadmium telluride (CdTe) films were deposited on glass substrates by direct current (DC) magnetron sputtering, and the effect of substrate-target distance (Dts) on properties of the CdTe films was investigated by observations of X-ray diffraction (XRD) patterns, atomic force microscopy (AFM), UV-VIS spectra, optical microscopy, and the Hall-effect measurement system. XRD analysis indicated that all samples exhibited a preferred orientation along the (111) plane, corresponding to the zinc blende structure, and films prepared using Dts of 4 cm demonstrated better crystallinity than the others. AFM studies revealed that surface morphologies of the CdTe films were strongly dependent on Dts, and revealed a large average grain size of 35.25 nm and a high root mean square (RMS) roughness value of 9.66 nm for films fabricated using Dts of 4 cm. UV-VIS spectra suggested the energy band gap (Eg) initially decreased from 1.5 to 1.45 eV, then increased to 1.68 eV as Dts increased from 3.5 to 5 cm. The Hall-effect measurement system revealed that CdTe films prepared with a Dts of 4 cm exhibited optimal electrical properties, and the resistivity, carrier mobility, and carrier concentration were determined to be 2.3 × 105 Ω∙cm, 6.41 cm2∙V−1∙S−1, and 4.22 × 1012 cm−3, respectively.
On‐wafer Hall‐effect measurement system
