research activities in 2007 - CSEM

PHOTONICS
Nicolas Blanc
The Photonics Division has over the last few years enjoyed a
steady growth in terms of income, number of employees and
technologies. To further sustain and reinforce CSEM activity in
this domain, major decisions were taken at the end of 2006
with a strong impact on key changes in the Photonics Division.
Firstly, the two sections “Image Sensing” and “Optoelectronics
Systems” moved in September 2007 from the Badenerstrasse
to its new site in Technopark Zürich, where CSEM Zurich
rents 1’1000 m2 . The completely new and modern
infrastructure includes several hundred m2 of lab space,
mostly optical labs with conditioned and filtered air. CSEM
Zurich benefits now from a very central location with excellent
public transport: Zurich main railway station is within
10 minutes and Zurich airport can be reached within
20 minutes by train. Moreover the new location offers many
potential synergies with nearby small- and medium-size
companies, including numerous start-ups and high-tech
corporations.
Secondly, the two sections “Micro-optical Systems” and
“Polymer Optoelectronics” moved in January 2008 to Basel to
build-up a new Division entitled “Functional Coatings”. This
Division is located in the Areal Rosental and will further
develop technologies related to passive (e.g. micro-optical
elements and optical security devices) as well as active (e.g.
polymer light-emitting devices, PLEDs) opto-electronics
components and systems, with a focus on organic materials
and moulding, embossing, as well as various printing
processes. The Functional Coatings Division benefits from
important investments including 500 m2 of fully equipped
clean rooms. CSEM presence in Basel is also expected to
significantly reinforce its R&D activity, in particular for
applications in the domain of Life Science, Chemistry and
Pharmaceutics.
On the scientific and technical side, the Photonics Division in
2007 kept its focus on the development of optoelectronic
components, including PLEDs, micro-optical elements and
image sensors, as well as their combination in highly
integrated and compact systems. One strategic axis remains
with the development of novel devices on the basis of polymer
materials which can be very advantageous in terms of costs
and for applications requiring large area devices. This is
notably achieved thanks to the use of low cost manufacturing
processes derived from the printing industry. In this field the
material properties and formulation are key to the
development and optimization of state-of-the art polymer
based optoelectronics components. In order to speed up the
screening and formulation of solvent processed organic LEDs,
a modified pipetting-robot together with an automated optoelectrical
characterization system have been developed. This
high-throughput apparatus allows the fabrication and
characterization of batches of 49 PLED samples in one
experimental run, enabling thus the systematic study of the
influence of parameter variations to the overall device
performances and providing extensive datasets for material
testing, device optimization and device modelling. A
concentration sweep of individual blend components can for
example quickly reveal the ideal blend ratio for optimum
composition.
3D-cameras based on the Time-of-Flight principle are able to
provide depth maps of their environment in real-time. Different
modulation schemes from continuous wave modulation,
pulsed mode and more complex modulations schemes can be
used as well. In all cases the 3D camera relies on an active
illumination that can be intensity modulated at high frequency.
Alternatively the detailed imaging of fast moving objects
(> 100 m/s) also calls for flash light illumination. For such
applications a new illumination unit has been realized based
on multi-mode vertical-cavity surface-emitting laser arrays.
This approach reaches modulation frequencies of up to
80 MHz and an optical peak output power of 1.3 Watt.
Miniaturization and low-power are two key characteristics of
CSEM heritage and these characteristics are reflected in
many projects. As an example within the European project
MuFly, CSEM has developed a miniaturized and light weight
360° camera module for autonomous micro aerial vehicles.
The camera fulfils stringent requirements: a power
consumption of less than 1 mW, a weight of less than 5 g and
small dimensions of ~2 cm3 , while providing a high dynamic
range in excess of 140 dB for reliable indoor and outdoor
operations under various illumination conditions. A further
example of miniaturization is provided in the development of a
highly integrated optical linear. The latter is designed to fit in a
volume of only 50 mm3 while providing spatial resolution in the
100 nm range at a speed of up to 5 m/s. This is achieved
thanks to a dedicated custom image sensor, a folded
telecentric optics manufactured by injection moulding and
further SMD components including a LED illumination and
passive elements, all components being mounted on one
single flexible print.
Last but not least CSEM has built up its capability in the
testing and qualification of integrated circuits and optical
sensors for small volume series. The testing of a circuit is an
essential but also quite an expensive step in the production
flow of semiconductor devices. Frequently CSEM customers
are looking for small volume production of components with
very high expectations with respect to quality. A testing
environment has thus been set up to support such production
verification and qualification in-house ensuring very short
qualification time after prototype evaluation. This is part of the
new offering of CSEM and in particular the Photonics Division
to its partners and customers.
33