Light confinement effect of nonspherical nanoscale solid immersion lenses

Abstract. We report on the light confinement effect observed in nonideally shaped (i.e., nonspherical) nanoscale solid immersion lenses (SIL). To investigate this effect, nanostructures of various shapes are fabricated by electron-beam lithography. When completely melted in reflow, these noncircular pillars become spherical, while incomplete melting results in nonspherically shaped SILs. Optical characterization shows that nonideal SILs exhibit a spot size reduction comparable with that of spherical SILs. When the size of the SIL is of wavelength scale or smaller, aberrations are negligible due to the short optical path length. This insensitivity to minor variations in the shape implies a large tolerance in nano-SIL fabrication.

[1]  E. Abbe,et al.  VII.—On the Estimation of Aperture in the Microscope. , 1881 .

[2]  Christoph Vannahme,et al.  High-Q conical polymeric microcavities , 2010 .

[3]  Helmut Schift,et al.  Fabrication of 3D nanoimprint stamps with continuous reliefs using dose-modulated electron beam lithography and thermal reflow , 2010 .

[4]  G. Whitesides,et al.  Soft Lithography. , 1998, Angewandte Chemie.

[5]  G. Kino,et al.  Solid immersion microscope , 1990 .

[6]  Kenneth E. Goodson,et al.  Microfabricated silicon solid immersion lens , 2001 .

[7]  Hans Peter Herzig,et al.  Comparing glass and plastic refractive microlenses fabricated with different technologies , 2006 .

[8]  Philip Kim,et al.  Near-field focusing and magnification through self-assembled nanoscale spherical lenses , 2009, Nature.

[9]  Myun-Sik Kim,et al.  Subwavelength-size solid immersion lens. , 2011, Optics letters.

[10]  Robert Brunner,et al.  Diffraction-based solid immersion lens. , 2004, Journal of the Optical Society of America. A, Optics, image science, and vision.

[11]  Chun-Yen Chang,et al.  New Nanometer T-Gate Fabricated by Thermally Reflowed Resist Technique : Instrumentation, Measurement, and Fabrication Technology , 2002 .

[12]  Myun-Sik Kim,et al.  Small-size microlens characterization by multiwavelength high-resolution interference microscopy. , 2010, Optics express.

[13]  Gregg T. Borek,et al.  Investigation of Micro Solid Immersion Lens Mounting Systems , 2007 .

[14]  Daniel R. Mason,et al.  Enhanced resolution beyond the Abbe diffraction limit with wavelength-scale solid immersion lenses. , 2010, Optics letters.

[15]  Myun-Sik Kim,et al.  Engineering photonic nanojets. , 2011, Optics express.

[16]  Charles Hockin,et al.  On the Estimation of Aperture in the Microscope , 1884 .

[17]  P. Nussbaum,et al.  Design, fabrication and testing of microlens arrays for sensors and microsystems , 1997 .