Experiments and Simulations of Infrared Transmission by Transverse Magnetic Mode through Au Gratings on Silicon with Various Air-slot Widths over the Period

Keywords:
gratings, infrared, SIBC, TM mode

Abstract:
Au gratings with various air-slot widths were fabricated experimentally by electron beam lithography system (e-beam) and their infrared (2.5~25 m) transmission of the transverse magnetic mode (TM mode) were investigated by the Fourier Transform Infrared Spectroscopy (FTIR). In our experiment, transmission dips and turning points were observed. In order to explain this phenomenon, simulations were used theoretically by the Maxwell equations and the surface impedance boundary condition (SIBC) method. Simulation results explain the relationship between surface plasma and transmission dips. These experimental and theoretical results can contribute to the understanding of TM-mode infrared transmission properties of metal gratings and the application on the field of infrared photo-detectors, bio-chip sensor, and light-emitting diode polarizers.

Nanotech 2008 Conference Program Abstract