近年来，如何实现用更少的硅原料和成本更低的原料质量获取可以接受的太阳能电池光电转换效率日益受到人们的广泛关注。硅微纳米结构太阳能电池具有优良的陷光性能和可以降低硅纯度等潜在优势，成为当前硅基太阳能电池的研究热点之一。本论文通过模拟仿真的方法计算了多种硅微纳米结构的太阳能电池光学、电学性能，设计出了具有广域光谱范围选择性增强光吸收和短载流子收集距离的硅微纳米结构。同时，在模拟结果基础上，利用金属催化硅腐蚀方法和碱腐蚀两步腐蚀硅的方法，从实验上制备了方口长颈漏斗结构。1，硅微纳米漏斗、倒锥、洞阵列的光吸收增强模拟研究硅材料由于其间接禁带的半导体性质，在太阳光谱的红光和近红外部分吸收能力很弱。工业上，单晶硅太阳能电池为了收集足够的太阳光，厚度一般在150微米以上，导致成本居高不下。单晶硅太阳能电池表面减反射结构是随机分布的微米级金字塔绒面和光学减反射薄膜，减反射的原因是绒面多次反射和特定厚度薄膜引起的半波损失，这两种策略无法应用在改善薄膜硅长波长光吸收能力弱的问题上。硅纳米线、锥、洞阵列结构可以在广域光谱范围上增强薄膜硅太阳能电池对太阳光的吸收能力。本论文在硅纳米洞阵列结构基础上，进一步设计了硅微纳米倒锥、漏斗阵列结构，其光吸收增强能力优于硅纳米线、锥、洞阵列。这两种结构可以有效延长光在吸收层的传播路径，实现了有效折射率从空气到硅的渐变，同时随着深度增加而周期性渐变的倒锥结构产生了针对不同波长光的共振态，可以实现广域光谱范围选择性光吸收增强。硅纳米漏斗结构具有更加适合光谱范围的周期性结构，因此光吸收性能优于倒锥，2.33微米厚漏斗结构的极限效率达到35.2%。2，方口长颈漏斗的实验制备及其光吸收增强模拟研究为了在实验上制备具有广域光谱范围选择性光吸收增强的硅微纳米结构，本文用化学镀的方法在硅片表面制备了稀疏分布的微纳米尺寸银颗粒，再利用银颗粒对硅的催化腐蚀形成洞，最后通过碱的各向异性腐蚀制备了方口长颈漏斗阵列。本文做了方口长颈漏斗阵列的光学性能计算，计算结果显示这种结构的光吸收增强能力强于硅微纳米洞阵列和硅微纳米倒金字塔阵列。3，硅纳米洞径向p-n结太阳能电池电学性能模拟研究本文建立了硅纳米洞径向p-n结的物理模型，假设少子扩散距离等于纳米洞洞壁厚度，用matlab编程计算了硅纳米洞径向p-n结太阳能电池的开路电压、短路电流、填充因子等电学性能。计算得出5微米厚的硅纳米洞光电转换效率能达到11.5%，说明纳米洞结构可以有效降低载流子的必要收集距离，从而降低太阳能电池对硅纯度的要求。

Using less silicon and lower purification cost without sacrificing too much convertion efficiency of solar cells is current research focus of photovoltaic devices in recent years. Silicon micro-nano structure solar cell receives more and more attention, due to its potential advantages allowing excellent light-trapping and carrier collection distance.In this work, several kinds of silicon micro-nano structures’ potential for solar cells were assessed according to optical and electrical simulation. One of these structures was fabricated through metal-catalyzed chemical etching method and alkali etching, whose size parameters were set based on the simulation results.1, Broadband optical absorption enhancement of silicon micro-nano funnel, invert cone and hole structure for photovoltaic application. Due to its indirect band gap, silicon shows very weak absorption on red and near-infrared fraction on solar spectrum. To absorb sufficient sun light, thickness of crystalline silicon solar must be over 150 micrometers in current photovoltaic industry, this inevitably leads to expensive material cost. Pyramid and antireflection thin films is the traditional strategies in the PV industry to reduce optical reflection; however, both of which are unsuitable for thin film silicon.The broadband solar spectrum optical absorption enhancement in silicon nano- wire, cone and hole structure for photovoltaic applications were widely studied. In this paper, silicon nano- funnel and invert cone structure is designed and investigated. It was found that both structures have more excellent absorption enhancement than nano- wire, cone and hole structure. These two structures could effectively prolong light propagation distance, gradually change the refractive index of film from air to silicon, and selectively enhance the specific wavelengths in broadband solar spectrum. Because of its suitable periodic structure funnel has more excellent absorption ability than invert cones. The ultimate efficiency of a funnel film with 2.33 micrometer thickness can reach 35.2%. 2, Fabrication and absorption enhancement simulation research of quadrate opening necked funnelI attempt to fabricate the silicon micro-nano structure with the ability of selectively enhancement at specific wavelengths during broadband solar spectrum. Firstly, the sparse silver micro-nano particles were prepared by electroless metal deposition method. Then hole was made by silver particles though metal-catalyzed chemical etching. Quadrate opening necked funnel structure was fabricated by alkali etch at last. The reflectance, transmittance and absorptance were calculated. The results confirmed that quadrate opening necked funnel has a stronger absorption enhancement than hole and inverted pyramid. 3, Electrical simulation of silicon nanoholes radial p-n junction solar cellsIn this work, a physical model of radial p-n junction silicon nano-holes structure was built, and open-circuit voltage, short-circuit current and filling factor are calculated under the assumption that minority carrier diffusion length equals the thickness of hole wall. As a result, the simulated PV efficiency can reach 11.5% with thickness of 5 micrometers. It indicates that nano-hole structure can reduce the collection distance of carriers and decrease the purity of silicon for solar cells.