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NASA NTRS · 20070018089

Silicon Nanotips Antireflection Surface for Micro Sun Sensor

Bae, Sam Y.·Lee, Choonsup·Mobasser, Sohrab·Manohara, Harish
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Abstract

We have developed a new technique to fabricate antireflection surface using silicon nano-tips for use on a micro sun sensor for Mars rovers. We have achieved randomly distributed nano-tips of radius spanning from 20 nm to 100 nm and aspect ratio of ~200 using a two-step dry etching process. The 30(deg) specular reflectance at the target wavelength of 1 (mu)m is only about 0.09 %, nearly three orders of magnitude lower than that of bare silicon, and the hemispherical reflectance is ~ 8%. By changing the density and aspect ratio of these nanotips, the change in reflectance is demonstrated. Using surfaces covered with these nano-tips, the critical problem of ghost images that are caused by multiple internal reflections in a micro sun sensor was solved.

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antireflectionMicro Sun Sensor (MSS)nanotechnolgoyMarsnano-tips

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Bae, Sam Y., Lee, Choonsup, Mobasser, Sohrab, Manohara, Harish. 2006-07-17. Silicon Nanotips Antireflection Surface for Micro Sun Sensor. https://ntrs.nasa.gov/citations/20070018089

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