A 45° saw-dicing process applied to a glass substrate for wafer-level optical splitter fabrication for optical coherence tomography

• Autor(a) principal: Maciel, M. J.
• Data de Publicação: 2016
• Outros Autores: Costa, C. G., Silva, M. F., Gonçalves, S. B., Peixoto, A. C., Ribeiro, A. Fernando, Wolffenbuttel, R. F., Correia, J. H.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/53794
• topic: optical coherence tomography; 45° saw-dicing technology; glass roughness; MOEMS; 45 degrees saw-dicing technology; Engenharia e Tecnologia::Nanotecnologia; Science & Technology

This paper reports on the development of a technology for the wafer-level fabrication of an optical Michelson interferometer, which is an essential component in a micro optoelectromechanical system (MOEMS) for a miniaturized optical coherence tomography (OCT) system. The MOEMS consists on a titanium dioxide/silicon dioxide dielectric beam splitter and chromium/gold micro-mirrors. These optical components are deposited on 45° tilted surfaces to allow the horizontal/vertical separation of the incident beam in the final microintegrated system. The fabrication process consists of 45° saw dicing of a glass substrate and the subsequent deposition of dielectric multilayers and metal layers. The 45° saw dicing is fully characterized in this paper, which also includes an analysis of the roughness. The optimum process results in surfaces with a roughness of 19.76 nm (rms). The actual saw dicing process for a high-quality final surface results as a compromise between the dicing blade’s grit size (#1200) and the cutting speed (0.3mm s−1). The proposed wafer-level fabrication allows rapid and low-cost processing, high compactness and the possibility of wafer-level alignment/ assembly with other optical micro components for OCT integrated imaging