TiO2颗粒在羟基表面的沉积行为及图案化

比较了3种具有羟基表面SiO2层的差异:紫外光照SAMs形成的羟基表面,紫外光照射前、照射后的羟基表面;用光照前后表面的差异,结合化学浴沉积技术在单晶硅基底上制得了TiO2微图案薄膜。系统考察了光源、硅片表面性质的变化、溶液等方面对图案生成的影响。实验表明TiO2沉积在未照区,电子和空穴动力学上的差异造成光照区表面正电荷增多,抑制了TiO2的沉积。该方法不需要光刻胶和自组装膜作为辅助模板,具有简单廉价的特点。

Deposition Behavior and Patterning of TiO2 Particles on Hydroxyl Surfaces

Three kinds of hydroxyl surfaces on SiO₂ layer are compared. The hydroxyl surfaces are formed by exposing the SAMs or the bare Si under UV light, and treating the bare Si surfaces only in piranha solution but not under UV light. Patterned TiO₂ thin films were fabricated on the Si substrates with the methods of UV irradiation and chemical bath deposition. The reasons for patterns formation were discussed in the view of the UV light, modifications of Si wafer and the aqueous solution. It was found that TiO₂ particles deposited onto the unirradiated regions. Different trapping/detrapping dynamics of the electrons and holes cause the holes to accumulate at SiO₂ surface in the irradiated regions, and restrain the deposition of TiO₂. The photoresist or self-assembled monolayers is needless in the process of patterning, so it is a simple and low-cost method.