【作者】 苗凤娟；

【导师】 王连卫；

【作者基本信息】 华东师范大学 ， 微电子学与固体电子学， 2010， 博士

【摘要】 近年,微结构材料特别是硅基半导体微结构材料的制备及其在能源、传感器等方面的应用已经成为物理、化学、材料、生物、电子等诸多学科领域学者所共同关注的焦点。微结构材料及其器件已经成为二十一世纪初信息技术发展的主要方向之一。本论文从一维、二维硅微结构材料——多孔硅一维光子晶体和硅微通道入手,首先研究了HF溶液中多孔硅一维光子晶体的形成机制,同时深入地研究了该微结构材料的制备方法,并通过大量实验进行参数优化,从而得到目标多孔硅一维光子晶体的制备工艺条件,随后开展了阵列化岛状多孔硅一维光子晶体在非制冷红外探测器中的应用研究；另一方面,制备了具有较高深宽比的硅微通道结构材料,并开展了它在超级电容器、直接甲醇燃料电池和生物传感器等方面的研究工作,成功制备了基于硅微通道负载金属镍(Ni/Si-MCP)、负载氧化镍(NiO/Si-MCP)和负载金属镍-钯(Ni-Pd/Si-MCP)的纳米复合电极,进一步研究了NiO/Si-MCP电极材料的电容特性,Ni/Si-MCP和Ni-Pd/Si-MCP两种复合材料电极对甲醇和葡萄糖的电催化氧化性能。实验和理论研究结果表明：阵列化岛状多孔硅一维光子晶体的制备方法及其在非制冷红外探测领域应用有一定创新和实用价值；硅微通道负载金属镍-钯复合电极的制备及其在直接甲醇燃料电池中的应用创新更具特色,对发展新型直接甲醇燃料电池一体化电极意义重大。总之,硅微结构材料在红外探测器、超级电容器、直接醇类燃料电池、生物传感器及生物燃料电池等领域均有着巨大的潜在应用价值。本论文主要研究内容和成果包括：本部分主要对多孔硅一维光子晶体的形成原理及相关理论基础进行了深入探讨,并在此基础上结合MATLAB软件对多孔硅一维光子晶体的工艺过程进行了参数模拟分析和讨论,为成功制备不同禁带中心波段的多孔硅一维光子晶体提供了理论支持。在此部分我们首先采用传输矩阵法并利用MATLAB软件对中心波段分别位于5μm、6μm、7μm、10μm的多孔硅一维光子晶体结构进行理论模拟分析和设计；其次在EC-LAB II(自制电化学实验平台)上采用ADLink2501数据卡和Labview软件对实验过程进行实时控制,调控样品制作过程中的最佳运行参数,制备目标样品；然后通过SEM和FTIR等测量技术对其氧化前后的的形貌及光学性能进行检测分析,结果发现氧化后出现禁带中心蓝移现象；最后讨论了其红外频谱宽角度反射器实现的可行性。为了更好地符合实际器件制作需求,我们结合上述各波段非阵列化光子晶体的制作过程参数及实验中氧化工艺影响,通过调整理论模拟及实验程控参数成功制备了中心波段位于12μm的阵列化岛状多孔硅一维光子晶体,为构建高灵敏度的非制冷红外探测器提供了有益的基础性工作。本部分阐述了如何结合传统微电子加工工艺与电化学腐蚀技术来制备硅微通道的方法,其中主要包括氧化、光刻、KOH溶液中倒金字塔诱导坑的刻蚀、HF溶液中低温程控刻蚀等工艺步骤,以及一些自制高深宽比硅微通道刻蚀设备结构特点和使用方法等。最后对制备样品进行测试和表征,结果显示用该方法可制备出开口为5μm×5μm,深度最高可达250μm,且形貌均一,结构完整的硅微通道结构。此外,探索了在硅微通道板上进行无磷化学镀Ni薄膜的工艺过程,并进一步研究了以NiO/Si-MCP纳米复合材料为电极材料制备新型超级电容器的可行性。本部分首先研究了直接甲醇燃料电池的现状和目前阳极催化剂所存在的最主要的问题,然后对制备好的硅微通道进行修饰改性,采用化学镀技术,在其表面和内壁上沉积了镍和镍-钯镀层,并对两种复合镀层材料进行表征后制备成电极,以检测其在碱性溶液中两种结构对甲醇的催化氧化性能。实验结果显示：Ni/Si-MCP纳米复合电极对甲醇存在敏感特性,但催化氧化活化电位较高；而Ni-Pd/Si-MCP纳米复合电极可以更容易和更好地催化氧化甲醇,并能极大降低甲醇氧化活化能；说明硅微通道是一个非常好的催化剂载体,它使催化剂分布得更加均匀且可提供较大的催化反应比表面积,较规则的通道也有利于溶液的流通。同时,一系列实验测试预示Ni-Pd/Si-MCP复合材料电极在直接甲醇燃料电池领域有极广泛的应用前景,为醇类生物燃料电池一体化催化电极的进一步研究提供了良好的平台。另一方面,本部分还进行了Ni/Si-MCP与Ni-Pd/Si-MCP复合材料电极对葡萄糖催化氧化的性能实验研究,结果显示两种复合材料电极都会对葡萄糖浓度敏感,但是Ni-Pd/Si-MCP复合材料电极对葡萄糖敏感度更高,其灵敏度可达81.4μA mM-1,检测限可达5μM。显示了Ni-Pd/Si-MCP复合材料电极在构建葡萄糖燃料电池和葡萄糖传感器方面有巨大潜力。综上所述,本文主要成果有：首先,制备了一种应用于红外热释电探测器衬底结构的既可绝热又可对特定波段红外光有较好反射效果的阵列化岛状多孔硅一维光子晶体结构,为构建高性能的硅基红外探测器衬底提供了可行方案；其次,发展了一种以硅微通道(Si-MCP)阵列为支撑结构的非贵金属电催化电极材料(Ni-Pd/Si-MCP),其催化剂分散良好,利用效率高；第三,研究了基于Ni-Pd/Si-MCP一体化催化电极对甲醇的催化氧化性能,研究结果表明该电极作为直接甲醇燃料电池(DMFC)的阳极材料对甲醇有良好的催化氧化能力,可实现较负的开启电位和较大的催化电流密度,在构建新型DMFC方面有巨大应用潜力；最后,讨论了Ni-Pd/Si-MCP复合材料电极在新能源以及生物传感器方面的应用。总之,该课题的研究方法及成果一方面对构建高效红外热释电探测器提供了新的可行方案,另一方面对发展低成本、可集成、一体化新型直接甲醇燃料电池或新型可集成生物传感器系统具有重要意义,为微纳技术在绿色能源和新型传感器器件应用领域研究提供了丰富素材,具有一定科研价值,其成果的进一步发展必将产生巨大的社会和经济效益。更多还原

【Abstract】 In recent years, the preparation and application of the microstructural materials, especially the microstructural semiconductors, have attracted more and more attention in the field of physics、chemical、material、electronics and etc.. The microsturctural and the micro-devices will initialize a new technology revolution in the 21st century.In this thesis, the preparations of one-dimensional and two-dimensional silicon microstructural materials, on the one hand, one-dimensional oxidized porous silicon photonic crystal were investigated firstly. The formation mechanisms and the preparation methods of one-dimensional oxidized porous silicon photonic crystal were studied deeply. Based on a large number of experimental a series of optimality conditions in experiment were obtained. The islands array of 1D porous silicon photonic crystal reflector for far infrared image detector was realized. On the other hand, Silicon microchannel (Si-MCP) thin film with high surface to volume ratio has been fabricated by conventional microelectronics technology. The technology of electroless plating nickel on Si-MCP and their potential application such as electrochemical supercapacitors, directed methanol fuel cells (DMFCs), biosensor and bio-fuel cells were studied deeply. Some innovative progresses had been achieved in the application in uncoolled infrared sensor based on 1D porous silicon photonic crystal reflector islands array, but the fabrication of Ni-Pd/Si-MCP electrode and their application in DMFCs and biosensor as well as bio-fuel cells were the key innovative content of this thesis. The mainly works are listed as following:The mechanism and the related theory of one dimensional porous silicon photonic crystal had been analyzed. Then in combination with the principle of silicon electrochemical etching and the software of Matlab, the parameters were proposed for the formation of one dimensional porous silicon photonic crystal.The most optimized parameters, such as current density, HF concentration, the type of substrate, the formation temperature, the RTO time and temperature were obtained by a serial of experiment. Then through the transfer-matrix method (TMM) designed, the porous silicon photonic crystals with the PBG gap ranging in mid 5,6,7μm were formatted. Considering device application of photonic crystal for uncoolled infrared sensors, concerns must be taken on the following issues. One was the cool part and the interconnections doesn’t need thermal insulator. Moreover, when fabricated large area Photonic crystal layers for sensor, the mechanical properties must had better stability. But the experimental results show that if increase the layers to enhance the optical properties, the surface of the photonic crystal will crack. More importance the interconnection between each unit was difficulty during application in devices. So the localization islands array of photonic crystal area was fabricated which PBG gap ranging in mid 12μm. Fourier transform infrared spectroscopy (FTIR) was applied to check the difference before and after oxidation, contrast and comparison with simulation. It is found that the center wavelength was shifted to short. When the incidence angle reaches 50°, it still had a wide bandwidth which proves to be a good reflective mirror within wide incidence angles (50°) for far-infrared wavelength.In this part, the fabrication process and the equipment of MCP were introduced briefly by the combination of lithography and electrochemical etching technology. From SEM images, it is clearly that the connective film is composed of a regular cube array with silicon walls between them. Both the length and width of the silicon MCP can be varied by choosing the etching time, enchant and temperature. In our experiments, the distance between each cube is about 1μm, the side length of each cube is about 5μm, and the depth can reach about 250μm. There are little impurities in each channel. Then the optimum conditions of electroless plating nickel films on Si-MCP were studied. The feasibility of Electrochemical Supercapacitors based on NiO/Si-MCP nanocomposite was discussed. The fabricated high surface to volume ratio silicon microchannel plates were modified by electroless plating Ni and Ni-Pd technology, the morphologies of the Ni/Si-MCP and Ni-Pd/Si-MCP composites were studied by SEM. The compositions of them were determined by EDS, and the catalytic abilities were obtained by a LK3200A electrochemical workstation (Tianjin, China).It is found that the 3D structure constitutes a proton conductive path from the catalysts to electrolyte membranes thereby playing an important role in the performance of the DMFCs and glucose biosensors or bio-fuel cells. Besides the good electronic conductivity, the silicon MCP had well-ordered channels that bode well for facile molecular transport of the reactants and products enhancing molecular conversion. The high volume to surface ratio increases the reaction area, and so more catalyst nanoparticles can be deposited onto the electrode surface resulting in the high surface reactivity. So this new catalyst supported by the silicon MCP electrode can significantly enhance the electrode kinetics.In conclusion, the silicon micorstuctural materials of one-dimensional oxidized porous silicon photonic crystal and silicon microchannel plates can be formed by electrochemical method under normal conditions. Their good performance make some potential cells and sensor application like direct methanol fuel cells and glucose biosensor.更多还原