American University of Beirut
Physics Department
Invites you to a presentation entitled
Micro- and Nano-fabrication in Semiconductors
By
Dr. Fouad Karouta
Australian National Fabrication Facility
Research School of Physics and Engineering
Australian National University
Abstract
Standard optical lithography based on mask aligners has a resolution limited to about 1 µm
feature size. In R&D environment sub-µm features are achieved using electron beam
lithography (EBL) with advantages such:
• Uses an electron-beam instead of light, hence ability to focus the e-beam to spot size of
10 nm.
• Electron scattering in the resist layer and backscattering from the substrate limit the
resolution to 20-30 nm.
• Flexibility of pattern (no masks / reticles).
The major disadvantage is the rather low speed of patterning.
The talk will describe the basics of this technique and highlights its capabilities through
some examples of the author realisation in photonic applications.
The talk will also cover another high tech instrument the so-called dual beam focused ion
beam (FIB) system that comprises an electron and ion beams. In milling mode energetic
Ga-ions can be used to mill locally any material. FIB technique is commonly used with
semiconductors, minerals, shells and also bio-materials. It is a very flexible nanofabrication and nano-characterisation tool like EDAX, STEM, EBIC to cite a few.
A few examples of FIB usage will be shown such:
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Preparation of TEM lamella in materials science.
3D reconstruction where sequential milling and SEM imaging is performed of a certain
interesting area of a sample followed by a 3D reconstruction of the milled materials
FIB can also be used to deposit a metal composite on a much localised area like nano-wires to
establish metal-material contact allowing electrical measurements.
Date: Monday, March 9, 2015
Time: 5:00 p.m.
Place: Emile Bustani for Physics, Rm. 333
Biography
Fouad Karouta has a chemistry degree from Lebanese University in Beirut, accomplished in
1986 his PhD in Montpellier University (France) on epitaxy and LEDs of InGaAsSb structures.
He joined Eindhoven University of Technology in The Netherlands at the Opto-electronic
Devices Section of the Department of Electrical Engineering, as post doc, assistant professor
(1987), associate professor (2000) till early 2009 before joining ANU as the ANFF ACT Node
Manager. Fouad has vast experience in managing research facilities and has been involved with
research in III-V compound semiconductors (GaAs, InP, GaN) for optoelectronic and
microelectronic applications for more than 30 years and has published and co-authored a large
number of papers on the subject.