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The authors report the resistive humidity sensors of Si-based thin film prepared by Al induced method on the glass substrates. Sensors were fabricated at annealing temperature of 500°C and time of 5, 45 and 90 minutes respectively. Experimental results indicate that the amorphous silicon (a-Si) thin film grow into crystal silicon (c-Si) with increasing annealing time. By measuring current-voltage characteristics of samples at 50°C show that the largest relative humidity (RH) ratio of 80% and 30% was obtained of the a-Si sample. For a-Si sample, it was found that current of sample increased from 7 × 10−10 to 1.3 × 10−7 A as we increased the temperature from 25°C to 80°C with 5 V applied bias and 80% RH. It was also found that measured current were 2.05 × 10−10, 4.67 × 10−9, 14.03 × 10−9, and 16.28 × 10−9 A when measured with 30, 50, 70 and 80%-RH, respectively.

In this study, the photonic bandgap (PBG) film with tunable mechanical properties and photonic stop band was prepared by a simple and feasible approach. Colloid polymer spheres with a relatively large diameter (approximate D n of 200 nm) and different glass transition temperatures (T g ) were blended with small polystyrene (PS) latex (D n 5 20 nm) and were subsequently casted on a substrate for 3 h at 50 C for self-assembly of the PBG film. The monodispersed polymer spheres were synthesized by soap-free emulsion polymerization in the boiling state. The T g values of the spheres were predetermined based on the Fox equation, and designed to fall in the region of 234 C to 112 C. Small PS could also be synthesized by this approach using the comonomer, sodium p-styrenesulfonate (NaSS), to ensure the small diameter. The long-range ordered structure constructed by embedding the small PS in the PBG film was indirectly confirmed on the basis of SEM analysis, from which the monochromatic film color was determined based on Bragg's diffraction law. Tunable film color was achieved by adjusting the diameter of the spheres, as evaluated using UV-Vis. Tunable mechanical properties of the PBG film were also achieved by varying the T g of the spheres or the filling ratio of small PS. Based on these approaches, the ultimate tensile strength could be tuned in the region between 0.39 to 4.7 Mpa, and the relative strain could be varied from 1236% to 16%, illustrative of the excellent deformability of the film. Furthermore, by variation of these two parameters, the film properties could be changed from typical elastomer behavior to brittle plastic polymer type behavior, greatly extending the prospective application fields.