Corporate Technology - Rolf Hellinger

Materials & Microsystems
Materials research has always had a big impact on Siemens’ product
and systems business. Products benefiting from this work range
from detectors for the latest generation of CT scanners and new
materials for LEDs to special coatings for turbine blades in power
generators, lead- and halogen-free materials for the electronics
industry, and sophisticated systems for analyzing nanomaterials.
More than 215 specialists are involved in these cross-sector
technologies at CT MM, where the focus is on evaluating environmental
impact and finding solutions that conserve resources.
Why Materials Matter
Researching new and enhanced materials is
in some respects similar to the process of innovation.
Decisive advances are not only a result
of radical new discoveries, but also of new
approaches to combining basic ingredients that
are already familiar. The professionals at Corporate
Technology’s Materials & Microsystems (CT
MM) division do both. In addition to synthesizing
new materials, they combine well-known
substances to produce completely new compositions.
And when the latter is done in the right
way, the result can be a customized material
with properties that are improved or often completely
new. Essential to all this is a precise understanding
of the atomic structure of materials
and of the kinds of properties these structure
produce. Equally essential is to have a full command
of the entire technological chain of
causes and effects, from raw materials and processing
to system integration and, ultimately,
recycling. To achieve this, researchers rely on
the latest findings from a variety of interdisciplinary
fields, including nanotechnology, rapid
prototyping, combinatorial chemistry, modeling,
and simulation.
Success stories in this area include a joint
project carried out by CT MM and Siemens subsidiary
Osram concerning the use of ceramic luminescent
materials for light-emitting diodes
(LEDs). The use of special luminescent material
mixtures is now making it possible to produce
LEDs that emit a broad palette of color shades.
This is not something to take for granted. Such
semiconductor materials normally produce
very pure colors, making them suitable only for
12 Corporate Technology
a limited color range. With the development of
what are known as “conversion” or “inorganic”
phosphors, however, it is already possible to
make blue LEDs emit light of a green, yellow,
red, or neutral white tone, and the same will
soon apply to ultraviolet LEDs. At the same
time, Osram has already launched an LED with a
luminosity of over 1,000 lumens — enough to
outshine a 50-watt halogen lamp. With that
kind of brilliance, Osram’s “Ostar Lighting” is
able to provide desk lighting from a height of
two meters. These new-generation LEDs, which
use 80 percent less energy than incandescent
lamps of equal brightness, are thus ready to unlock
a billion-dollar market for general lighting
applications. LEDs are already used in various
fields — as backlights in monitors, for example,
in vehicle cockpit lighting, brake lights, and
now even for headlights. In a discipline known
as light engineering, experts at CT MM are developing
new types of lighting that involve a
combination of luminescent materials with
photonic crystals, which makes it possible to
precisely control and enhance the color, intensity,
and propagation of light.
Walls of Light
A logical development from this field is the use
of materials specially tailored to produce organic
LEDs (OLEDs). Developed only a few years
ago, these ultra-thin luminescent plastics offer
very high contrast and are suitable for video applications.
Their most common area of use is in
displays, but OLEDs are also well-suited to deliver
evenly-cast colored or white light across
large areas.
This paves the way for completely new applications
and lighting effects in fields including
architecture, advertising, and interior design.
Potential products include illuminated wallpaper,
luminescent ceiling units, and flexible,
transparent walls of light. Together with engineers
at Osram, researchers from CT are pushing
ahead with the development of OLED-based
light sources that are suitably long-lived and
consistently bright.
When it comes to the detectors used in CT
scanners, which produce high-resolution,
three-dimensional X-ray images of the inside of
the body, speed is of the essence. In the latest
CT scanners, the X-ray source and detectors are
rotated around the patient’s body three times