为了实现低成本高灵敏度的表面增强拉曼散射效应，制备了一种基于硅表面纳米结构的表面增强拉曼散射效应(SERS)衬底。首先利用低能反应离子注入的方法对单晶硅进行表面处理，制作高陡值度的墙壁结构。然后采用电子束蒸发的方式在硅片表面蒸镀银膜，高密度的银纳米点阵列出现在侧壁表面，形成大量的热点。实验采用罗丹明6G(R6G)作为探针分子进行表征，发现获得最强拉曼信号的银膜厚度为40 nm，R6G的探测极限能达到10-14 mol/L；同时分析衬底的重复性和稳定性，发现在614 cm-1和1 650 cm-1处的拉曼信号特征峰的相对标准偏差分别达到12.3％和14.3%，保存一个月的衬底测得的拉曼信号强度保持不变。本研究提供了一种操作简单、成本低的制备高灵敏度增强拉曼效应衬底的方法，制备的衬底具有高信号可重复性和高稳定性的优点。

An innovative formaldehyde gas sensor based on thin membrane type metal oxide of TiO₂layer was designed and fabricated. This sensor under ultraviolet (UV) light emitting diode (LED) illumination exhibits a higher response to formaldehyde than that without UV illumination at low temperature. The sensitivities of the sensor under steady working condition were calculated for different gas concentrations. The sensitivity to formaldehyde of 7.14 mg/m³is about 15.91 under UV illumination with response time of 580 s and recovery time of 500 s. The device was fabricated through micro-electro-mechanical system (MEMS) processing technology. First, plasma immersion ion implantation (PIII) was adopted to form black polysilicon, then a nanoscale TiO₂membrane with thickness of 53 nm was deposited by DC reactive magnetron sputtering to obtain the sensing layer. By such fabrication approaches, the nanoscale polysilicon presents continuous rough surface with thickness of 50 nm, which could improve the porosity of the sensing membrane. The fabrication process can be mass-produced for the MEMS process compatibility.

采用金催化化学腐蚀和钝化两个过程成功制备了黑硅。利用原子力显微镜、分光光度计、红外光谱仪和光致发光光谱仪分别对黑硅的微观结构、反射率、表面状态和发光性能进行了研究。结果表明:黑硅表面呈现山峰状的微观结构,其平均反射率可低至3.31%。光致发光光谱上出现了3个发光峰，分别由量子限制效应、硅氧烯、杂质和缺陷引起。

采用液相沉积法在硅基底上成功制备了二氧化硅薄膜, 利用扫描电子显微镜、光电子能谱和少子寿命测试仪等对二氧化硅薄膜的组织结构和钝化性能进行了研究, 结果表明, 液相生长的二氧化硅薄膜致密平整, 含有少量的F元素; 对硅具有较好的减反和钝化作用, 平均反射率由28.87%降低至10.88%, 表面复合速度由6 923 cm/s降低至2 830 cm/s。