High‐performance colored aesthetic semitransparent organic photovoltaics (OPVs) featuring a silver/indium tin oxide/silver (Ag/ITO/Ag) microcavity structure are prepared. By precisely controlling the thickness of the ITO layer, OPV devices exhibiting high transparency and a wide and high‐purity color gamut are obtained: blue (B), green (G), yellow‐green (YG), yellow (Y), orange (O), and red (R). The power conversion efficiencies (PCEs) of the G, YG, and Y color devices are greater than 8% (AM 1.5G irradiation, 100 mW cm−2) with maximum transmittances (TMAX) of greater than 14.5%. An optimized PCE of 8.2% was obtained for the YG OPV [CIE 1931 coordinates: (0.364, 0.542)], with a value of TMAX of 17.3% (at 561 nm). As far as it is known, this performance is the highest ever reported for a transparent colorful OPV. Such high transparency and desired transmitted colors, which can perspective see the clear images, suggest great potential for use in building‐integrated photovoltaic applications.

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In this study the nonlinear behavior of a buck converter was simulated and the responses of Phases 1 and 2 and the chaotic phase were investigated using changes of input voltage. After a dynamic system model had been acquired using basic electronic circuit theory, Matlab and Pspice simulations were used to study system inductance, resistance, and capacitance. The characteristic changes of input voltage, and phase plane traces from simulation and experiments showed nonlinear behavior in Phases 1 and 2, as well as a chaotic phase. PID control and Integral Absolute Error (IAE) were used as adaption coefficients to control chaotic behavior, and particle swarm optimization (PSO) and the genetic algorithm were used to find the optimal gain parameters for the PID controller. Simulation results showed that the control of chaotic phenomena could be achieved and errors were close to zero. Fuzzy control was also used effectively to prevent chaos. The experimental results also showed nonlinear behavior from Phases 1 and 2 as well as the chaotic phase. Laboratory experiments conducted using both PID and fuzzy control echoed the simulation results. The fuzzy control results were somewhat better than those obtained with PID.

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This study investigated the use of pulsed direct current (DC) magnetron sputtering for depositing indium-gallium-zinc oxide (IGZO) thin films that can serve as channel layers and fabricating high-performance thin-film transistors (TFTs). Unlike a typical radio-frequency (RF) sputtering system, a pulsed DC system can be operated using a modulated pulse frequency for increasing the deposition rate, reducing the surface roughness, and increasing plasma density for dense thinfilm deposition with reduced arc-induced structural defects at a specific sputtering power. In this study, pulse frequencies ranging from 170 to 350 kHz were modulated for obtaining IGZO thin films with higher surface flatness, carrier mobility, and material quality than those of IGZO films deposited using RF sputtering. The IGZO film fabricated at a pulse frequency of 350 kHz was used as a transistor channel layer in one of the fabricated TFTs; this TFT showed an advantageous field-effect mobility of 9.78 cm 2 V −1 s −1 , a subthreshold swing of 0.72 V/decade, an off current of 1.57 × 10 −11 A, and an on-off current ratio of 4.87 × 10 7 . These results revealed that pulsed DC sputtering is a promising technique for fabricating TFTs with excellent device characteristics.