Deposition of Nanostructured CdS Thin Films by Thermal Evaporation Method: Effect of Substrate Temperature

Abstract

Nanocrystalline CdS thin films were grown on glass substrates by a thermal evaporation method in a vacuum of about 2 × 10−5 Torr at substrate temperatures ranging between 25 °C and 250 °C. The physical properties of the layers were analyzed by transmittance spectra, XRD, SEM, and four-point probe measurements, and exhibited strong dependence on substrate temperature. The XRD patterns of the films indicated the presence of single-phase hexagonal CdS with (002) orientation. The structural parameters of CdS thin films (namely crystallite size, number of grains per unit area, dislocation density and the strain of the deposited films) were also calculated. The resistivity of the as-deposited films were found to vary in the range 3.11–2.2 × 104 Ω·cm, depending on the substrate temperature. The low resistivity with reasonable transmittance suggest that this is a reliable way to fine-tune the functional properties of CdS films according to the specific application.

Mitigating Reasons for the Poor Performance of n‐CdS/p‐SnS Solar Cells

“…Standard Tauc method was used to estimate the bandgap of CdS layers. CdS layer was found to have a direct bandgap of E g ≈ 2.42 eV which matched those reported in most of the literature . The UV–vis absorption spectra of p‐SnS active layers, after baseline subtraction of glass/ITO/CdS spectrum, were used to determine the bandgap.…”

“…CdS layer was found to have a direct bandgap of E g ≈ 2.42 eV which matched those reported in most of the literature. [12,23,24] The UV-vis absorption spectra of p-SnS active layers, after baseline subtraction of glass/ITO/CdS spectrum, were used to determine the bandgap. Table 1 reports the bandgap of p-SnS absorber layer of different thicknesses along with those reported in our previous study.…”

ReX2 (X=S,Se): A New Opportunity for Development of Two-dimensional Anisotropic Materials

“…传统的 2D 材料 CVD 合成除了以上方法以外, 还有原子层沉积(ALD) [105][106] 、热蒸镀 [107] 、磁控溅 射 [108] 、分子束外延(MBE) [109] 等。Hämäläinen 等 [110] [47][48][111][112] , 各向异性的介 电性导致不同取向的折射率差异, 进而体现在光学 各向异性上。而 ReX 2 线性二色性的光学各向异性, 已经在角度依赖的光吸收 [112][113][114][115] 、激子 [116][117][118][119][120][121][122] 中得到 证明。Sim 等 [122] 在少层 ReS 2 中发现激子光学斯塔 克效应, 图 6(a)展示了泵浦探测少层 ReS 2 纳米片各 向异性激子示意图。他们利用线性偏振光极化 ReS 2 观察到角度依赖的光激子吸收, 如图 6(b)和(c)所示, 非简并激子随极化角度会呈线性变化, 通过拟合得 到, X 1 , X 2 各向异性激子最大极化光吸收分别在 19°和 87°。…”

Ga doping of nanocrystalline CdS thin films by electrodeposition method for solar cell application: the influence of dopant precursor concentration

“…A range of techniques have also been used to produce CdS both in bulk and thin film forms. These methods include close space sublimation [8], thermal evaporation [9], sputtering [10], spray pyrolysis [11], metal organic chemical vapour deposition [12], pulsed laser deposition [13], molecular beam epitaxy [14], sol-gel [15], chemical bath deposition (CBD) [16] and electrodeposition [17]. With the opening up of renewable energy as a new field of technology in recent times, there has been a renewed interest in the research on CdS with respect to its application in solar cells.…”