Share Email Print

Proceedings Paper

Electron beam lithography for nanofabrication of metal induced Bragg reflectors
Author(s): Rossella Capasso; Lucia Petti; Pasquale Mormile; Martina De Laurentis; Andrea Irace; Giovanni Breglio
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Electrically Induced Bragg Reflectors can be very attractive to realize programable waveguides networks. Their practical realization is nevertheless intrinsically connected to the capability to make a peculiar comb-structure electrode on the top of the waveguides with typical period of 200 nm (corresponding to the Bragg length) and a tolerance of few nanometers. In this work, the experimental fabrication of these comb-structure electrodes by means of electron beam lithography is described. We fabricated large areas 1D periodic gold structures with nanometer resolution by using a high resolution electron beam lithography (EBL) process and a post-processing technique based on lift-off. These electrodes can be employed as Induced Bragg Reflectors in a multilayer structure for a not permanent periodically modulation of the effective refractive index of the guiding structure. The desired structures are obtained with nanometric resolution by means of EBL, digging furrows of rectangular section in both a polymetilmethacrylate (PMMA) and in α-chloromethacrylate and α-methylstyrene (ZEP) layer spin-coated on silicon, then evaporating a metal layer (Au) on the top and then by lift-off of metal. The EBL technique allows a very accurate control of the dielectric distribution of the exposed area able to produce feasible, high efficiency periodic and photonic band-gap structures. The resulting 1D gratings are made of metal lines 100 nm wide with a period of 200 nm and, 120 nm wide with a period of 250 nm, respectively. Large area structures (up to 1 mm x 6 μm) have been realized with nanometre resolution and they have been characterized by scanning electron microscopy (SEM). These structures will be used in a future work of ours to realize 40 GHz switching speed modulator by inducing a Bragg Reflector with a reverse biased vertical InP/InGaAsP p-i-n diode according to the predictions of the grating reflectivity spectra and of the transient response.

Paper Details

Date Published: 3 May 2011
PDF: 10 pages
Proc. SPIE 8068, Bioelectronics, Biomedical, and Bioinspired Systems V; and Nanotechnology V, 80681A (3 May 2011); doi: 10.1117/12.886493
Show Author Affiliations
Rossella Capasso, Institute of Cybernetics, CNR (Italy)
Univ. of Naples Federico II (Italy)
Lucia Petti, Institute of Cybernetics, CNR (Italy)
Pasquale Mormile, Institute of Cybernetics, CNR (Italy)
Martina De Laurentis, Univ. of Naples Federico II (Italy)
Andrea Irace, Univ. of Naples Federico II (Italy)
Giovanni Breglio, Univ. of Naples Federico II (Italy)

Published in SPIE Proceedings Vol. 8068:
Bioelectronics, Biomedical, and Bioinspired Systems V; and Nanotechnology V
Ángel B. Rodríguez-Vázquez; Rainer Adelung, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?