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E u r o S c i C o n C o n f e r e n c e o n
Nanotechnology &
Smart Materials
Nano Research & Applications
ISSN 2471-9838
O c t o b e r 0 4 - 0 6 , 2 0 1 8
Am s t e r d a m , N e t h e r l a n d s
Nanotechnology & Smart Materials 2018
Page 24
E
tching of semiconducting materials with the atomic level resolution is of
a high interest to technologies addressing fabrication of low dimensional
devices, tunability of their optoelectronic properties and precise chemical control
of device surfaces and interfaces. The so-called digital etching (DE) process that
takes advantage of self-limiting reactions was introduced almost 30 years ago
for processing of Si devices. This concept has also been explored for etching of
GaAs, GaAs/AlGaAs, Ge1xSix compounds, SiO2, SiN and some other materials.
Conventional DE consists of a series of two cycles, each involving a limited or self-
limited reaction step followed by a step designed to remove reaction products from
processed surfaces. Typically, 0.1-1.5 nmof material is etched in each cycle which
is calculated based on post-processing measurements. The lack of diagnostics
that would allow monitoring this process
in situ
is a significant drawback of
conventional DE techniques. We have demonstrated that for photoluminescence
(PL) emitting GaAs/AlGaAs nanoheterostructures, it is possible to carry out PL-
monitored photocorrosion in cycles analogous to those employed in DE. The
advantage of this digital photocorrosion (DIP) process, carried out in liquids that
support photocorrosion, but do not react significantly with materials in darkness,
is that it could be carried out in cycles with a sub-monolayer resolution and
simultaneously monitored with PL. Recently, we have demonstrated that DIP could
also be monitored with open circuit potential (OCP) measurements. An excellent
agreement between the position of GaAs/AlGaAs interfaces revealed during
photocorrosion by PL and OCP suggests that DIP could also be monitored
in situ
for othermaterialswith non-measurable PL. I will discuss fundamental parameters
describing this novel diagnostics process, as well as its application for both
sensing and nanostructuring of III-V quantum semiconductors. The perspective
of congruent decomposition of compound semiconductor nanoheterostructures
with
in situ
monitored atomic layer resolution will also be discussed
Biography
Jan J Dubowski received his PhD degree in Semiconductor
Physics from the Wroclaw University of Technology, Poland. He
is a Canada Research Chair and a full Professor at the Depart-
ment of Electrical and Computer Engineering of the University
de Sherbrooke, Canada. He is a Fellow of SPIE- The Internation-
al Society for Optics and Photonics (citation: “For innovative
methods of investigation of laser- matter interaction”). He has
published over 200 research papers, reviews, book chapters
and conference proceedings. He is an Associate Editor of the
Journal of Laser Micro/Nanoengineering, Biosensors and Light:
Science & Applications.
jan.j.dubowski@usherbrooke.caPhoto atomic layer etching: an innovative
tool for nanostructuring of quantum
semiconductor microstructures
Jan J Dubowski
3IT-Université de Sherbrooke, Canada
Jan J Dubowski, Nano Res Appl Volume:4
DOI: 10.21767/2471-9838-C6-023