纳米Au膜在口腔呼吸检测器中的应用

以纳米Au膜材料为核心反应器,用硫化氢气体代替口腔呼吸气来检测巯基化合物的浓度变化,实验采用桥式电路,以复射式直流检流计作为测试手段,以电流显示读数。进而以不同的Au膜粗糙度和不同的Au膜厚度分别对硫化氢的浓度进行测试,同时,对比实验数据探索吸附规律。结果表明:在良好的控制条件下,气体体积分数与测试结果成线性关系。     

基于二维金属亚波长孔阵列结构的MEMS红外辐射源特性研究

以MEMS红外气敏传感器为应用目标,采用MEMS技术设计和制作一种二维金属亚波长孔阵列结构红外辐射源。探讨了不同厚度SU-8膜对金属/电介质/金属(M/D/M)二维金属亚波长孔阵列结构在中远红外波段透射特性的影响。设计并制作了Au/SU-8/Au的M/D/M结构,测试采用傅里叶变换红外光谱仪器。同时对M/D/M结构不同电介质层情况下的中远红外波段透射特性进行了模拟。实验结果表明,SU-8厚度在小于1μm时,透射强度远大于厚度1μm以上的结构,且有透射强度最大值出现(SU-8厚度为360nm),同时,随着SU-8厚度的增加,透射谱峰值呈现规律性红移。     

金属电极的腐蚀特性研究

对金属电极的腐蚀特性进行了研究。实验中设计了多种不同的金属电极,通过改变电极材料、电极厚度、电极层数、腐蚀液成分及温度等条件,研究了金属电极的腐蚀特性。通过研究发现,电极的腐蚀特性跟电极材料、电极厚度、电极层数、电极的缺陷及应力、腐蚀液成分及温度等条件有关。最后设计了一种打底层金属材料为Tiw,层厚20 nm,上层金属为Au,层厚度为200 nm的金属电极,在覆盖一层光刻胶,并对光刻胶进行后烘坚膜的情况下,在常温下,用HF溶液腐蚀1 h后,SOIMEMS微结构完全释放,金属电极还十分完好。     

金(Au)/钯(Pd)复合膜表面等离子共振氢敏传感器基因优化

提出了一种新颖的基于波长调制的Au/Pd复合膜SPR氢敏传感器结构,采用遗传基因算法对Au/Pd复合膜氢敏传感器的灵敏度进行了数值计算和优化,优化结果表明:Au(2 nm)/Pd(27 nm)结构的复合膜氢敏传感器可获得最佳的灵敏度,与通常使用的单一纯Pd(20 nm)膜氢敏传感器相比,不仅氢敏传感器的敏感膜的稳定性得到改善,而且灵敏度也提高了近3倍.     

Ag-TiO2薄膜表面等离子体共振光谱特性研究

以拓宽Ag膜波长调制型表面等离子体共振(SPR)传感器的工作波长区间,将TiO2膜沉积于Ag膜表面制成Ag-TiO2复合薄膜.利用数值计算方法对不同厚度Ag膜和As-TiO2复合膜波长调制型SPR光谱特性进行仿真研究.仿真结果表明:共振吸收峰显著依赖于Ag膜厚度;当保持Ag-TiO2复合膜厚度60 nm时,复合薄膜SPR波长随TiO2厚度的增大而向长波长方向移动,发现红移;与60 nm厚Ag膜共振波长相比,12 nm厚TiO2与48 rnm厚Ag组成的复合膜共振波长红移超过200 nm.     

磁记录非牛顿液膜润滑仿真

随着记录密度的不断提高，头盘浮动间隙不断减小。目前近场光、磁混合记录已经在研究10nm以下的浮动系统。由于浮动间隙已远小于空气分子平均自由程(室温下约65nm)而有使气膜浮动技术有失效的危险。非牛顿液膜浮动技术就是在这种背景下在近几年备受关注的。该文提出了一个新的非牛顿润滑液膜，建立了考虑表面粗糙度影响的非牛顿液膜浮动系统模型，对不同表面粗糙度形状系数进行了仿真研究。研究表明，非牛顿液膜浮动系统的性能与气膜的情况有很大的差异。     

微膜尺寸与吸附物对微膜生化传感器动态特性的影响

以微膜生化传感器为研究对象,利用ADINA软件进行模态分析,获得了微膜生化传感器在液态介质影响下的固有频率,分析了微膜结构尺寸和吸附物对传感器动态性能的影响。研究表明：微膜生化传感器的固有频率随着微膜厚度的增大而增大,随着微膜半径的增大而减小。吸附物质量使传感器的固有频率降低,吸附物的吸附位置也对传感器的固有频率产生影响。     

中国微米纳米 花状Au-SnO2复合材料的制备及其对甲醛气敏性能的研究

利用水热法合成了花状SnO2微米材料,并以它作为基体,对其进行Au纳米颗粒修饰,得到了花状Au-SnO2复合材料.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)分析等表征手段对所制备的Au-SnO2复合材料进行了表征分析,结果表明,这种花状结构的材料是由厚度为30 nm～60 nm的SnO2纳米片自组装而成,其尺寸为1 μm～2 μm.同时,我们用花状SnO2和Au修饰的花状SnO2复合材料对1×10-6～500×10-6的甲醛进行了气敏性能测试.结果表明,通过Au修饰,花状SnO2对甲醛的气敏性能有了极大的提高.当甲醛浓度为200×10-6时,其灵敏度(Ra/Rg)约为120,是花状SnO2敏感材料的8倍,表现出很高的响应.另外,由Au修饰的花状SnO2复合材料制成的敏感元件对甲醛表现出良好的选择性.这可能归因于Au纳米颗粒高效的催化活性促进了甲醛气体的扩散和O2的吸附,从而使其表现出更加优异的气敏性能.     

MEMS制造中精确测量薄膜厚度的方法研究与比较

精确测量各种功能薄膜的厚度在微机电系统（ MEMS）制造加工过程中有非常重要的意义。利用接触式表面轮廓仪、光谱椭偏仪、电感测微仪、扫描电镜、原子力显微镜和工具显微镜分别测量了10 nm～100μm各种薄膜的厚度。比较了不同测量仪器的测量范围、分辨率和对样品的适用性,分析了薄膜厚度测量过程中误差产生的机理。实验结果表明：当存在膜层台阶时,10 nm～100μm的膜厚测量均可采用接触式表面轮廓仪,对于硬度较高的膜层可采用电感测微仪,对于厚度小于0.5μm的膜层可采用原子力显微镜;对于可观察样品侧面、厚度大于0.7μm的膜层可采用扫描电镜,工具显微镜适用于μm级膜层,对于厚度大于20μm的膜层不宜采用光谱椭偏仪。     

液晶型化学传感器检测有机胺化合物的研究

该实验报道了一种以微米级沟槽状Au膜为基底的液晶型化学传感器;通过在具有微米级沟槽(一个沟槽周期5μm)的玻璃基底上进行平面镀金,制备了具有相同沟槽周期的Au膜;并在Au膜上制备巯基十一酸自组装敏感膜。传感器对乙胺检测的线性范围不是单一线性曲线;乙胺浓度在0～0.3g/m3,线性方程y=-0.18x 0.0028,相关系数r=0.9891;乙胺浓度在0.3～1.6g/m3,线性方程y=-0.04x-0.0046,r=0.9901。证实微米级沟槽状Au膜为基底制作的液晶型化学传感器可以用于检测目标化合物。     

Fabrication of IZO transparent conducting thin films by the use of magnetron sputtering equipped with ion‐beam system

Abstract— Indium zinc oxide (IZO) thin films have been prepared on glass, polycarbonate (PC), and polyethylene terephthalate (PET) substrates by using a radio‐frequency (RF) magnetron sputtering system equipped with an ion gun, and a simple OLED device was made by using IZO film. The influence of the RF power, the Ar gas volume, and the substrate temperature during the deposition process on the roughness and the electrical and optical properties of the films have been investigated. In addition, End‐Hall ion‐beam treatment of the substrates is applied before the sputtering deposition process. The sheet resistance of the IZO films is 25 Ω/□ for the glass, 21 Ω/□ for the PC, and 20 Ω/□ for the PET substrate with a thickness of 150 nm, and the lowest root‐mean‐square (rms) roughness of these IZO films were measured to be 0.58, 0.35, and 0.32 nm for glass, PC, and PET substrate, respectively. The decrease in the sheet resistance of the IZO films becomes evident after the ion‐beam treatment and makes the surface of the thin film more hydrophilic. Relative to non‐treated IZO film, the ion‐beam‐treated IZO anode in the OLED device seems to inject holes into the emitting layer to enhance the current density.     

应用静电纺丝法制备PZT纳米纤维薄膜

提出应用静电纺丝法制备PZT纳米纤维薄膜。研究中配制PZT溶液后再进行静电纺丝,获得了PZT纳米纤维薄膜,并且通过调整纺丝时间和沉积次数来控制纳米纤维薄膜的厚度。运用SEM对获得的热处理前后的薄膜进行了观察对比,测量其平均直径约为200 nm;运用XRD对退火后的样品进行分析,测得样品的主要成分为Pb(Zr0.52Ti0.48)O3,证明所制备的正是PZT薄膜;运用AFM测得薄膜的表面粗糙度为1.034 nm,说明该纳米薄膜材料非常的均匀整齐。     

Thermal conductivity measurement of submicrometer-scale silicon dioxide films by an extended micro-Raman method

The micro-Raman method is a noncontact and nondestructive method for thin film thermal conductivity measurements. To apply the micro-Raman method, however, the thickness of the film must be at least tens of micrometers. An analytical heat transfer model is presented in this work to extend the micro-Raman measurement method to measure the thermal conductivity of thin films with submicrometer- or nanometer-scale thickness. The model describes the heat transfer process in the thin film and substrate considering the effects of thin film thickness, interface thermal resistance, thermal conductivity of the thin film and substrate. From this heat transfer model, an analytical expression for the thermal conductivity of the thin film is derived. Experiments were successfully performed to measure the thermal conductivity of 200, 300 and 500 nm thickness silicon dioxide films using the extended micro-Raman measurement method, with results confirming the accuracy and validity of the extended model.     

SnO2基薄膜气体传感器制作与敏感性测试

在现有的粉末烧结型SnO2基气敏传感器基础上研制了薄膜型SnO2基气体传感器,以抛光的丽热石英玻璃为基片,真空磁控溅射50～70nm厚度的SnO2薄膜,在SnO2薄膜上分别溅射不连续的ZnO、Al2O3、CeO2、InO2等薄膜,传感器背面溅射30μm的Ni80Cr20电阳合金作为传感器加热电阻,用薄膜热电偶测量传感器工作温度。测试了不同的复合瞑对传感器灵敏度和选择性的影响,并对传感器的吸附与解吸速度进行了测试,薄嗅传感器达到相同灵敏度所需的工作温度比粉末烧结型传感器下降100～150℃,吸附解吸速度比粉末烧结型快。     

纳米金膜对巯基化合物的吸附特性研究

纳米薄膜由于表面的高活性而具有一些特殊的性能,气敏特性就是最主要的性质之一。纳米金膜在吸附巯基化合物后,金膜的平面电阻会发生相应的变化。实验中,以真空离子溅射镀膜法在不同基材表面溅镀一层约15 nm厚的金薄膜,通过桥式测量电路,研究了金膜吸附丙硫醇挥发气体后,由于平面电阻改变而引起的电流变化的规律和相关的影响因素。实验数据表明:纳米金膜能够对体积分数为20×10-6的硫醇气体产生明显响应。     

石英湿法腐蚀及侧壁晶棱修平工艺研究

以石英陀螺的微结构为研究对象,对石英的湿法腐蚀规律进行研究.选用500 μn厚Z切向石英片,蒸镀10 nm厚Cr膜和200 nm厚金膜作为掩模层,选用40%氢氟酸和40%氟化铵的1:1混合溶液作为腐蚀液.通过在不同温度下的腐蚀试验,表明腐蚀速率随温度增加而增大,温度过低腐蚀过慢影响腐蚀效率,温度过高使石英侧壁表面粗糙度增加.经过试验摸索,在70℃下腐蚀,可获得表面质量较好的石英微结构.石英在湿法腐蚀中结构侧壁会产生两级晶棱,根据侧壁主要晶面的腐蚀速率,计算出修平侧壁两级晶棱所需时间分别为8h和27h,经过试验验证,在预计时间内,石英侧壁晶棱基本修平.     

A novel method to fabricate single crystal nano beams with (111)-oriented Si micromachining

Single crystal beams made by (111)-oriented Si micromachining are usually anchored to the substrate directly. It is difficult to use the beams as resonators, since they are electrically connected to the substrate. This paper presents a modified process to fabricate single crystal nano beams which are electrically isolated from the substrate. In this process, the single crystal nano beams are fully released from the substrate and mechanically supported by metal wires, which also serve as electrical connections. The metal wires are much stiffer than the beams and do not degrade the mechanical properties of the beam according to simulations. The length and width of the beams are determined by photolithography. The thickness of the beam and the gap between the beam and the substrate are determined by the dry etching and KOH etching processes. The influence of KOH etching on the beam thickness is documented through ongoing experiments. At present, the double clamped beams and the cantilever beams have been fabricated. The thinnest beam to date was measured to be 47 nm. The resistance between the beam and the substrate was measured to be 214GΩ, while the resistance of a 147 nm-thick beam was measured to be 816 Ω. The surface roughness of the (111) plane is also discussed. The RMS surface roughness of the nano beam was measured to be 1.08 nm in an area of 5 μm × 5 μm, which was etched with 45%wt. KOH at 50°C.     

Silver (Ag) as a novel masking material in glass etching for microfluidics applications

In this paper, we report the use of a single masking film for deep glass etching in hydrofluoric acid (HF). Thin film silver (Ag) is the key masking material in this work enabling a simple and low cost fabrication of microfluidic structures. The Ag film was deposited by evaporation and etched in a diluted nitric acid and de-ionized water solution at a ratio of 1:3. Surface morphology for different thicknesses of Ag film and its correlation to the maximum achievable etch depth is analyzed. AFM results shows low roughness values (<5 nm), indicating the Ag films are of smooth surface. With a 100 nm Ag film, a 220 μm etch depth in borosilicate glass substrates were produced and by further thickening the Ag to 300 nm, etch depths exceeding 300 μm were successfully achieved. SEM images show that thinner Ag films are of finer grains, potentially a source for pinholes formation where rapid penetration of HF along the grain boundaries peels off the Ag film from the glass surface. However, the Ag film was found not to react with HF. The process was demonstrated in the fabrication of cavities for integration with other microfluidic devices.     

Pyrex玻璃的ICP刻蚀技术研究

以SF6/Ar为刻蚀气体,采用感应耦合等离子体(ICP)刻蚀Pyrex玻璃,研究气体流量、射频功率对刻蚀速率及刻蚀面粗糙度的影响.采用正交实验方法找出优化的实验参数,得到Pyrex玻璃刻蚀速率为106.8 nm/min,表面粗糙度为Ra=5.483 nm,实验发现增加自偏压是提高刻蚀速率、减小刻蚀面粗糙度的有效方法.