Presented are experimental results on the effect of concentration, aging, and annealing time on the optical and structural properties of sol gel zinc oxide (ZnO) and Al-doped ZnO thin films. ZnO and ZnO:Al thin films were fabricated on glass substrates using spin coating followed by annealing. XRD confirmed that the films are polycrystalline wurtzite. For low concentration films (0.2 and 0.4 M), grain size increased with aging time up to 72 hours. For high concentration samples (0.6 and 0.8 M), grain size increased only up to 48 hours. Additional aging resulted in a decrease in the grain size. The largest grain sizes were found for 0.4 M at 72 hours and 0.6 M at 48 hours. The band gap tended to decrease with increasing aging time for all concentrations. The smallest band gap for each aging time (24, 48, and 72 hours) was observed for 0.6 M films. These results suggest that higher concentration sol gel near 0.6 M may yield better properties with shorter aging times than 0.2 and 0.4 M films. Annealing data suggests that 350 oC is the minimum annealing at 1 hour to achieve high-quality films and higher concentration ZnO films have stronger diffraction peaks. ZnO:Al also exhibits stronger diffraction peaks and a larger blue shift of the band edge with increasing sol gel concentration.

中文翻译：

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浓度，时效和退火对溶胶凝胶ZnO和Al掺杂ZnO薄膜的影响

提出了有关浓度，老化和退火时间对溶胶凝胶氧化锌（ZnO）和掺铝ZnO薄膜的光学和结构性质的影响的实验结果。ZnO和ZnO：Al薄膜是在玻璃基板上使用旋涂法制成的，然后进行退火处理。XRD证实该膜是多晶纤锌矿。对于低浓度薄膜（0.2和0.4 M），晶粒尺寸会随着时效时间的增加而增加，长达72小时。对于高浓度样品（0.6和0.8 M），晶粒尺寸最多仅增加48小时。额外的时效导致晶粒尺寸减小。发现最大晶粒尺寸为72小时为0.4 M，48小时为0.6M。对于所有浓度，带隙都随着老化时间的增加而减小。对于0.6 M膜，观察到每个老化时间（24、48和72小时）的最小带隙。这些结果表明，与0.2和0.4 M薄膜相比，0.6 M附近的高浓度溶胶凝胶可产生更好的性能，且老化时间更短。退火数据表明，350℃是在1小时内获得高质量薄膜的最低退火温度，而更高浓度的ZnO薄膜具有更强的衍射峰。随着溶胶凝胶浓度的增加，ZnO：Al还表现出更强的衍射峰和更大的能带边缘蓝移。