Semiconductor microlenses fabricated by one-step focused ion beamdirect writing

摘要

We fabricated a refractive semiconductor micro-lenses using anfocused ion beam (FIB) direct writing technique. The simple one-step FIBnprocess produced high-quality micro-lenses of silicon, the most popularnand low cost semiconductor material used in optoelectronics. A sphericalnSi microlens with a nominal lens diameter of 48 Μm exhibited a radiusncurvature and focal length of 100 and 40 Μm, respectively. Thenmaximum derivation between the measured and designed profiles is lessnthan Λ/100. The surface roughness, RMS, measured by use of atomicnforce microscope in 1× 1 Μm2 square area, is 1.1 nm.nThis microlens fabrication method could be readily applicable due to thensimplicity in processing and the high-quality results