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A composite film of poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and titanium carbide nanoparticles (TiC-NPs) was deposited on an indium doped tin oxide–poly(ethylene naphthalate) (ITO–PEN) conducting plastic substrate by a doctor blade technique. This ITO–PEN substrate with the composite film was used as the flexible counter electrode (CE) for a plastic dye-sensitized solar cell (DSSC). Performances of the plastic DSSC with the platinum-free CEs containing PEDOT:PSS/TiC-NPs composite was investigated. A solar-to-electricity conversion efficiency (η) of 6.50% was achieved for the pertinent DSSC with PEDOT:PSS/TiC-NPs composite, using commercial N719 dye, which exhibited comparable performance to that of a cell with a sputtered-Pt film on its CE (6.84%). The homogeneous nature of the composite film PEDOT:PSS/TiC-NPs, the uniform distribution of TiC-NPs in its PEDOT:PSS matrix, and the large electrochemical surface area of the composite film are seen to be the factors for the best performance of the pertinent DSSC. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to characterize the TiC-NPs. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy dispersive X-ray spectroscopy (EDX) were used to characterize the films. The high efficiency of the cell with PEDOT:PSS/TiC-NPs is explained by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and incident photon-to-current conversion efficiency (IPCE) curves.

Thin oxides thermally grown on the reactive-ion-etched (RIE) silicon substrates in N2O and diluted O2 ambients have been studied. The RIE will strongly affect the silicon surface microroughness and lead to poor oxides properties. Using the after-treatment-chamber (ATC) process, CF4 addition in the O2 plasma can further improve the time-zero-to-dielectric-breakdown (TZDB) characteristics of the thin oxides as compared with pure O2 plasma. This is because CF4 addition in the ATC can remove the damaged silicon layer and smooth the silicon surface since the O2 plasma can effectively only strip the polymeric layer. In addition, the N2O-grown oxides can enlarge the process window of the CF4/O2 ATC treatments with respect to pure oxides.

Thin oxides thermally grown in reactive-ion-etched (RIE) silicon substrates in N2O and diluted O2 ambient have been studied. The microroughness of the oxide-silicon interface was investigated using a spectrophotometer, atomic force microscopy (AFM), and cross-sectional high-resolution electron microscopy (HRTEM). The microroughness is strongly dependent on the RIE conditions and the post etching treatments. Furthermore, oxidation-enhanced interface microroughness has been observed. As compared with the pure oxides grown in diluted oxygen, N2O-grown oxides exhibit stronger immunity to RIE-induced damage. N2O oxidation of the etched specimens treated with an after-treatment-chamber (ATC) process result in the best electrical properties.

Thin-film transistors (TFTs) with a double-active-layer (DAL) structure have been proposed and found to exhibit two kinds of special electrical characteristics. One is the improvement of current drivability and transconductance as compared to the traditional structure. The other is the double-switching characteristics caused by the bi-transistor action. By means of a buried oxide separating the conduction channel into two parts, carrier transport could be enhanced due to the reduction of the vertical electric field. In addition, the weak avalanche breakdown for the top channel results in hole accumulation in the top poly-Si/buried oxide interface, further promoting the conduction of the bottom active layer, leading to the novel double-switching properties.

Both polysilicon films low-pressure chemical-vapor-deposited (LPCVD) at 625° C and amorphous films deposited at 550° C with subsequent annealing at 600° C for 24 h to form polysilicon films were used to grow polyoxides at 850° C in wet or dry oxygen. Detailed high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) studies have been performed to determine the microstructures of the polyoxide/polysilicon interface and the crystallinity of the polysilicon films. It is found that the oxidation phenomena of these two films are very different. For the recrystallized amorphous silicon specimens, the polyoxide/polysilicon interface is very flat because of the poor crystallinity and low-angle grain boundaries between the grains. On the other hand, the polyoxide/polysilicon interface is rough for the as-deposited polysilicon samples due to the distinct grain characteristics and the high-angle grain boundaries between these grains.