随着微纳米技术的发展，出现了多种以微纳米为载体的甲烷传感器。其中，微纳米 电离式甲烷传感器采用纳米尖端阵列构成的微电晕放电结构，具有响应快、灵敏度高的 特点，在甲烷传感领域展现出新的应用潜力。然而，目前微电晕放电结构参量对放电性 能的影响机制、以及甲烷与空气混合气体放电效应机理的研究不够完善，难以对器件性 能优化提供有效理论指导。因此，本文围绕以上两个方面展开研究，主要内容如下：

1. 为了揭示微电晕结构参量与电场的耦合关系及其对放电发展的共同作用机制， 建立了微电晕器件在氮气（N₂）与氧气（O₂）混合气体中的放电仿真模型，分析了器 件放电的动态发展规律；然后研究了不同间距和电压下，阴极纳米线曲率半径对放电特 性的影响，结果表明：纳米线曲率半径与放电电流呈非单调关系；增大半径会减小尖端 场强，对放电有削弱趋势，但同时会增大阴极尖端面积，从而导致电离面积和二次发射 面积增大，对放电有增强趋势，这二者共同决定最终放电结果。

2. 为了揭示空气与甲烷（CH₄ ）混合气体中微电晕随甲烷浓度变化的气敏机理，分 析了器件在不同电极间距和纳米线曲率半径下的甲烷气体敏感性能，结果表明：器件在 低浓度甲烷范围内（0.5%–15%）气敏性和线性度较好，在间距为10μm、曲率半径为 0.05 μm 时低浓度甲烷气敏性最佳；然后分析了微电晕随甲烷浓度变化的单值敏感规律， 结果表明：增大甲烷浓度会增强电场并促进电离反应，CH4相关正离子（CH₃⁺、CH₄⁺ ） 逐渐在放电中占据主导地位，当CH₄浓度超过N₂浓度时，CH₃⁺的增长会受到抑制。

3. 为了验证仿真模型的准确性以及微电晕器件的气敏特性，通过金属辅助化学刻 蚀法制备了基于硅纳米线阵列的微电晕型器件；然后进行了空气中的放电测试实验，结 果表明：实验电流与仿真电流变化趋势一致，验证了仿真模型的合理性和准确性；最后 进行了器件在甲烷浓度为0.5%-5%范围内不同间距中的气敏性实验，结果表明：实验 电流变化趋势与仿真一致，器件在该甲烷浓度范围中具有较好的线性度和灵敏性。

本文分析了微电晕型器件动态放电过程和结构参量对放电特性的影响机制，在此 基础上分析了器件对甲烷的敏感性能及敏感机理，并进行了实验验证和性能对比分析， 为基于微电晕型器件的甲烷传感器奠定了理论基础。

With the development of micro-nano technology, a variety of methane sensors based on micro- and nano-scale structures have emerged. Among them, micro-nano ionizing methane sensors, which employ micro-corona discharge structures formed by arrays of nanoscale tips, exhibit fast response and high sensitivity, demonstrating promising potential in methane sensing applications. However, the influence mechanisms of structural parameters on the discharge performance of micro-corona devices, as well as the discharge effect mechanisms in methane air mixtures, remain insufficiently studied, hindering effective theoretical guidance for device optimization. Therefore, this study focuses on these two aspects, and the main content is as follows:

1. Toreveal the coupling mechanism between parameters such as tip electric field strength andemission area andthedischarge characteristics of micro-corona devices, a simulation model was established for the device operating in a nitrogen (N₂) and oxygen (O₂) gas mixture. The dynamic evolution of the discharge process was analyzed. Subsequently, the effects of varying cathode nanowire curvature radii on discharge behavior were investigated under different elec trode spacings and applied voltages. The results show that the relationship between nanowire curvature radius and discharge current is non-monotonic: increasing the radius reduces the tip electric field strength, suppressing the discharge, but also enlarges the cathode tip area, expand ing both the ionization and secondary emission regions, thereby enhancing the discharge. The final discharge result is determined by the interplay of these competing effects.

2. To explore the sensing mechanism of micro-corona devices in air–methane (CH₄) mix tures with varying methane concentrations, the gas sensitivity of the device was analyzed under different electrode spacings and nanowire curvature radii. The results show that the device ex hibits good sensitivity and linearity in the low methane concentration range (0.5%–15%), with optimal sensing performance achieved at an electrode spacing of 10 μm and a curvature radius of 0.05 μm. Furthermore, the discharge response to methane concentration was studied. The results indicate that increasing methane concentration enhances the electric field and promotes ionization reactions. Methane-related positive ions (CH₃⁺ , CH₄⁺) gradually dominate the dis charge process. However, when the CH4 concentration exceeds that of N₂, the generation of CH₃⁺ becomes suppressed.

3. Toverify the accuracy of the simulation model and evaluate the sensing performance of the micro-corona device, silicon nanowires array was fabricated using metal-assisted chemical etching to construct the micro-corona structure. Discharge experiments were conducted in air, and the results show that the experimental discharge current trends are consistent with the sim ulation results, validating the model’s rationality and accuracy. Finally, sensing experiments were carried out within the methane concentration range of 0.5%–5% under different electrode spacings. The experimental current variation closely matched the simulation, and the device demonstrated good linearity and sensitivity within this concentration range. This study analyzes the dynamic discharge process of micro-corona devices and the in fluence of structural parameters on their discharge characteristics.

Based on this, the methane sensing performance and underlying response mechanisms were further examined. Experimen tal validation was performed, providing atheoretical foundation for the developmentofmethane sensors based on micro-corona discharge technology.