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This study investigates InSnZnO thin films deposited using mist chemical vapor deposition with different nitrogen (N 2)/oxygen (O 2) ratios of carrier gases. The crystallinity and bandgap of InSnZnO are not affected by the carrier gases; however, the content of the oxygen deficiency of the InSnZnO thin films reduces when the N 2 /O 2 mixed carrier gases have higher oxygen ratio. The InSnZnO thin-film transistor (TFT) shows the highest field-effect mobility (65.04 cm2V−1s−1) when N 2 is used as the carrier gas to deposit the InSnZnO thin film. Although the field-effect mobility of the InSnZnO TFT that uses the N 2 (60 vol%)/O 2 (40 vol%) mixed carrier gas to deposit InSnZnO thin film is the lowest (47.65 cm2V−1s−1), it is still higher than those of the amorphous InGaZnO thin film transistors (∼10 cm2V−1s−1). Furthermore, the InSnZnO TFT using the N 2 (60 vol%)/O 2 (40 vol%) mixed carrier gas to deposit InSnZnO thin film exhibits the steepest subthreshold slope (102 mV/dec), the largest on/off current ratio (4.6 × 107), and the most stable electrical characteristics after the negative bias stress test for 10,800 s. [ABSTRACT FROM AUTHOR]

The urban heat island effect in cities has become an important problem in relation to not only urban climate but also public health and urban planning. Tainan, which located in Southern Taiwan, is a compact city with intense development. Therefore, this study investigated the urban thermal condition by employing a high-density street-level air temperature observation network (HiSAN). A total of 100 measurement points were set in various urban development areas. The geographic factors in Tainan can be used for indicating the relationship between thermal conditions and urban built environments to comprehensively compare the approaches, such as conducting traverse measurement and utilizing only a single datum or a small amount of weather station data. Buffer zone analysis was used in this study for zones of different sizes, and it was determined that a 300-m scale is optimal to illustrate the effects of land features on microclimate. The results revealed that the thermal condition in Tainan is influenced by urban development factors, such as the floor area and land cover area, and by geographic factors, such as the distance to the sea. A better cooling effect can be obtained from a vegetation area during the night time and from a water body during the daytime. Moreover, different cooling effects are observed based on the distance to the sea. Through these results, a model for predicting the thermal condition for different periods can be established using a multiple regression model. Urban planners and architects can proffer design and planning suggestions for different areas based on the findings of this study to reduce thermal stress in urban areas. Unlabelled Image • The HiSAN with buffer analysis clearly indicate the characteristics of UHI in Tainan. • Urban features have different effects on the thermal condition at different times. • Water ratio in daytime and vegetation in nighttime have positive cooling effect. • The built-up area is favored to located near the coastal for better thermal comfort. • The Ta prediction model can be built by the urban development and geographic factors. [ABSTRACT FROM AUTHOR]