We describe a novel solid state crystallisation method for optimising a thin film transparent conductive oxide when deposited on flexible polymer substrates. The method is based on ultra-short non-thermal laser sintering of indium tin oxide (ITO) thin films. In this study, we used commercial ITO thin films deposited on a flexible polyethylene terephthalate substrate with a relatively low melting temperature compared with ITO on glass. We demonstrate the use of laser scanning with high pulse overlapping at fluences seven times less than the threshold required for melting/damage of ITO. The results confirm greater than four times enhancement in the mobility of charge carriers of ITO thin films after laser scanning and sheet resistance can be reduced up to 25%. There is no reduction in optical transparency observed in laser treated samples. Surface morphology and x-ray diffraction analyses confirm the improvement in crystallite sizes by laser sintering, resulting in a greater than 37% increase in grain size due to enhanced crystallization. Comparison of experimental and simulation based on a delayed two temperature model confirms that ITO thin film crystallization occurred at about one-third of the melting temperature of ITO.

我们描述了一种新颖的固态结晶方法，用于在沉积在柔性聚合物基板上时优化薄膜透明导电氧化物。该方法基于氧化铟锡 (ITO) 薄膜的超短非热激光烧结。在这项研究中，我们使用商业 ITO 薄膜沉积在柔性聚对苯二甲酸乙二醇酯基板上，与玻璃上的 ITO 相比，其熔化温度相对较低。我们展示了使用高脉冲重叠的激光扫描，其能量密度比 ITO 熔化/损坏所需的阈值小七倍。结果证实，激光扫描后 ITO 薄膜的电荷载流子迁移率提高了四倍以上，薄层电阻可降低高达 25%。在激光处理的样品中没有观察到光学透明度的降低。表面形态和 X 射线衍射分析证实，激光烧结改善了微晶尺寸，由于结晶增强，晶粒尺寸增加了 37% 以上。基于延迟的两个温度模型的实验和模拟的比较证实 ITO 薄膜结晶发生在 ITO 熔化温度的大约三分之一处。