| Effects of micro and nano textures of silicon substrate on the hydrophobicity and reflection of the surface for solar- cell applications |
| Paper ID : 1308-UFGNSM-FULL |
| Authors: |
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mohsen kazemi arjas1, Mahdiye Mehran *2, arash mokhtari3 1RF MEMS and Bio-Nano Electronics Lab, Department of Electrical Eng, Shahid Bahonar University of Kerman, Kerman, Iran 2Iran-kerman_Shahid Bahonar un 3Optical and RF Communication System (ORCS) Lab, Department of Electrical Eng, Shahid Bahonar University of Kerman, Kerman, Iran |
| Abstract: |
| Efficiency of solar cells is significantly affected by their surface structures. One of these important structural properties is surface morphology. Solar cells with micro and/or nano-textured surfaces absorb more incident radiation while reflection from these substrates reduces, so the efficiency improves. There are different methods toward texturization of silicon substrate. Among them wet chemical processes are the simplest and cheapest methods. Alkali solutions such as KOH are the most common etchant for the evolution of square-based pyramid structures on the silicon substrate, which increase the light absorption and reduce the reflection of the silicon surface. Metal Assisted Chemical Etching (MACE) is an anisotropic wet etching method that is capable of producing high aspect ratio semiconductor nanostructures from patterned metal film. This method is a simple, cost-effective and industry-applicable approach. In this paper, we incorporate micro pyramids and subsequently, nanowires to the silicon substrate by an anisotropic etching using KOH and MACE process, respectively. Modified MACE process is used to incorporate high aspect ratio Si nanowires on the pyramids of the silicon substrate. To achieve this, Ag nanoparticles are utilized as the catalyst in MACE process. Studying FE-SEM images of samples reveal that micro pyramids are formed in sizes between 3 to 7µm while silicon nanowires are in diameter range of 50 to 300nm, heights of 2 to 5µm and spacing of 50 to 100nm. Decorated silicon pyramids with nanowires enhance the absorption of the silicon surface considerably besides reducing the reflection. Additionally, hydrophobic property of this surface also increases which makes it a promising choice for solar cells. |
| Keywords: |
| Solar cells, Nanostructures, Microstructures, Silicon nanowier, Light reflection, Light absorption,Metal Assisted Chemical Etching (MACE) |
| Status : Paper Accepted (Poster Presentation) |
