Porous Silicon Fabrication Process for Optical Reflectors

  • Ying Yue
  • Nian Zhen Wuhan University of Technology
Keywords: Porous silicon, non-manhattan, high aspect ratio, MEMS, wet etching


We describe the use of porous silicon fabrication technique for fabricating non-manhattan structures in silicon using wet etching. The fabrication method is simple to set up, economical and produces smooth etched surface. A solid source diffusion of N++ in a P type wafer with low stress thermally grown silicon nitride is used as a masking layer. Comparison of porous silicon etches with wafers solid source diffusion and implanted diffusion is presented. The result show that areas where a solid source diffusion is used form an etch angle of 70-80°, however using an implanted diffusion the etch angle is closer to 90°. The selectivity of the etch during porous silicon fabrication using any of the above two as masking layer results in fabrication of high aspect ratio non-manhattan structures. These structures since are wet etched do not have surface roughness and can be used for optical applications.


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Author Biography

Nian Zhen, Wuhan University of Technology

School of Power Engineering, Wuhan University of Technology


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How to Cite
Yue, Y., & Zhen, N. (2018). Porous Silicon Fabrication Process for Optical Reflectors. EPH - International Journal of Applied Science (ISSN: 2208-2182), 4(5), 01-07. Retrieved from https://ephjournal.com/index.php/as/article/view/754