金催化的硅纳米线的可控制备及光学特性研究

Research on controllable preparation and optical properties of gold catalysed silicon nanowires

硅纳米线是新型一维半导体纳米材料的典型代表。利用阳极氧化铝薄膜为模版复制出具有有序纳米结构的金膜,在金的催化辅助下对单晶硅进行湿法刻蚀,得到尺寸、形状、分布可控的硅纳米线阵列,并对其光学特性进行了研究。研究结果表明,金代替银作为催化剂,可以有效地抑制二次刻蚀,金的化学性质相对于银更加稳定,克服了银膜在较高的温度或较长刻蚀时间下产生的结构性破坏,得到形貌规整、尺寸可控的硅纳米线阵列。对该阵列在400nm^1200nm波段的反射率、透过率进行了测试,并对比分析了金模板催化与传统方法机理的异同。测试结果表明,相较于传统金属辅助化学刻蚀法,文中提出的金模板催化法制备的硅纳米线阵列尺寸及分布更加均匀可控,在宽光谱范围内的抗反射性得到了显著提高。

Silicon nanowires are the typical representative of new one-dimensional semiconductor nanomaterials.The ultrathin anodic aluminium oxide membrane was employed as the template for reproducing ordered ultrathin gold nanomeshes array.The silicon nanowires arrays with controllable size and shape distribution were prepared by wet etching of monocrystalline silicon under the catalysis of gold film,and their optical properties were studied.The results show that the chemical properties of gold instead of silver as a catalystare more stable than that of silver,which can effectively avoid the secondary etching and overcome the structural damage of silver film at higher temperature or longer etching time,and the silicon nanowires arrays with regular shape and controllable size can be obtained.The reflectivity and transmissivity of the arrays in the band of 400 nm^1200 nm were tested,and the similarities and differences of mechanism between the gold film catalysis and the conventional method were compared.The test results indicate that,compared with conventional metal-assisted chemical etching,the size and distribution of silicon nanowires arrays prepared by the gold film catalytic method proposed are more uniform and controllable,and the anti-reflective properties are effectively improved in broadband spectrum.