Investigação de aspectos topológicos de componentes e dispositivos microfabricados em silício

• Ano de defesa: 2010
• Autor(a) principal: Rodolfo Felipe de Oliveira Costa
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Engenharia Elétrica; Engenharia elétrica
• Link de acesso: http://hdl.handle.net/1843/BUDB-8D4LXJ

The main goal of this work was the investigation of the roughness on the surface of silicon wafers subjected to etching with a KOH aqueous solution, as well as on microstructures and micro-optical components produced a KOH etching technique that yields smooth spherical pits. The performance and reliability of devices and micro-fabricated components is strongly related to roughness, the understanding and control of which is of utter importance to the success and advancement of micro-systems. Micro-fluidic, electro-mechanical and optical systems are fields where micro-manufacturing roughness produced by the processes has been a limiting factor for further miniaturization of these devices and to the enhancement of their performance. This dissertation covered the most relevant concepts related to the selective etching of silicon, the roughness and the technique for the achievement of spherical cavities by anisotropic etching of silicon with KOH. Equipment used to measure roughness, parameters that affect the surface roughness, and a detailed description of the process used to produce structures are also referred to throughout this text. We could demonstrate that the components produced by an array or superposition of spherical cavities arefeasible for applications in optics, micro-optics, and ophthalmic wavefrontanalysis, since for these applications the values of roughness should be lower than ë/10, where ë is the wavelength of light used, typically between 550 nm and 850 nm. We demonstrate the technique to produce a silicon microlens array for wavelengths above 1100 nm, already in the range of the infrared spectrum, aiming at an enhanced performance of infrared cameras. A number of suggestions for the reduction of the surface roughness during the microstructure etching steps are also presented.