Title :
Broadband antireflection for III-V semiconductors by subwavelength surface grating structures
Author :
Yugami, Hiroo ; Kanamori, Yoshiaki ; Kobayashi, Kenichi ; Hane, Kazuhiro
Author_Institution :
Graduate Sch. of Eng., Tohoku Univ., Sendai, Japan
Abstract :
Recently, it is demonstrated that the subwavelength grating (SWG), which is the surface-relief grating with the period smaller than the wavelength of light, behaves as an antireflection surface. In particular, a tapered SWG suppresses reflection over a wide spectral bandwidth. The SWG is more stable than the multilayered thin film, since it is fabricated from a single material. In this study, we demonstrate broadband antirefraction properties of III-V materials (GaSb) by using SWG. The surface nano-structures with 200-350 nm periods are fabricated by means of electron beam lithography and fast atom beam (FAB) etching. The reflectivity of the sample is strongly suppressed from the visible to near IR region. The experimental data is compared with numerical simulations using the rigorous coupled analysis (RCWA).
Keywords :
III-V semiconductors; antireflection coatings; diffraction gratings; electron beam lithography; etching; gallium compounds; light reflection; nanostructured materials; nanotechnology; optical fabrication; reflectivity; refractive index; semiconductor thin films; surface structure; ultraviolet spectra; GaSb; III-V semiconductor; antireflection surface; broadband antireflection; broadband antireflection properties; electron beam lithography; fast atom beam etching; numerical simulation; reflectivity; refractive index; rigorous coupled analysis; subwavelength surface relief grating structure; surface nanostructure; ultraviolet spectra;
Conference_Titel :
Photovoltaic Energy Conversion, 2003. Proceedings of 3rd World Conference on
Conference_Location :
Osaka, Japan
Print_ISBN :
4-9901816-0-3
