Download Organic Electronics

Executive Briefing
Topic 3 – Information Systems Technology
Organic Electronics
Dan Ru
ISYM 540 – SSII
Current Topics in ISM
July 16th, 2009
Introduction
Organic electronics, plastic electronics or polymer electronics, is a branch of electronics that
deals with conductive polymers, plastics, or small molecules. It is called 'organic' electronics
because the polymers and small molecules are carbon-based, like the molecules of living things.
This is as opposed to traditional electronics (or metal electronics) which relies on inorganic
conductors such as copper or silicon.
Polymer electronics are laminar electronics, that also includes transparent electronic package and
paper based electronics.
In addition to organic Charge transfer complexes, technically, electrically conductive polymers
are mainly derivatives of poly-acetylene black (the "simplest melanin"). Examples include PA
(more specifically iodine-doped trans-poly-acetylene); poly-aniline: PANI, when doped with a
protonic acid; and poly (dioctyl-bithiophene): PDOT.
Conductive polymers are lighter, more flexible, and less expensive than inorganic conductors.
This makes them a desirable alternative in many applications. It also creates the possibility of
new applications that would be impossible using copper or silicon.
Organic electronics not only includes organic semiconductors, but also dielectrics, conductors
and light emitters.
New applications include smart windows and electronic paper. Conductive polymers are
expected to play an important role in the emerging science of molecular computers.
In general organic conductive polymers have a higher resistance and therefore conduct electricity
poorly and inefficiently, as compared to inorganic conductors. Researchers currently are
exploring ways of "doping" organic semiconductors, like melanin, with relatively small amounts
of conductive metals to boost conductivity. However, for many applications, inorganic
conductors will remain the only viable option.
Organic electronics can be printed.
Printed Electronics
Printed electronics is a set of printing methods used to create electrically functional devices.
Paper has been often proposed to be used as substrate but due the rough surface and high
humidity absorption other materials such as plastic, ceramics and silicon has been applied more
widely. Several printing processes have been piloted and printing preferably utilizes common
printing equipment in the graphics arts industry, such as screen printing, flexography, gravure,
offset lithography and inkjet. Instead of printing graphic arts inks, families of electrically
functional electronic or optical inks are used to print active or passive devices, such as thin film
transistors or resistors. Printed electronics is expected to facilitate widespread and very low-cost,
low-performance electronics useful for applications not typically associated with conventional
high performance (i.e., silicon-based) electronics, such as flexible displays, smart labels,
decorative and animated posters, and active clothing.
The term printed electronics is often used in association with organic electronics or plastic
electronics, where one or more functional inks are composed of carbon-based compounds. While
these other terms refer to the material system, the process used to deposit them can be either
solution-based, vacuum-based, or some other method. Printed electronics, in contrast, specifies
the process, and can utilize any solution-based material, including organic semiconductors,
inorganic semiconductors, metallic conductors, nano-particles, nano-tubes, etc.
Organic Printed electronics integrates knowledge and developments from printing technology
and electronics as well as from chemistry and materials science, especially from organic and
polymer chemistry. An important basis is the development of organic electronics, which itself is
based on the development of organic electronically functional materials. Beside the electronic
functionalities (conductor, semiconductor, electroluminescence etc.) the ability to process in
liquid form (as solution, dispersion or suspension) of such materials led to the development of
printed electronics. However, beside this also inorganic materials, which can be processed in
liquid form, are used.
As far as printed electronics is concerned with devices from organic electronics, these in part
differ from conventional electronics in terms of structure, operation and functionality. Therefore
design and optimization of devices and circuits under consideration of the actual fabrication
method play an important role in the development of printed electronics.
Smart Glass
Smart glass or switchable glass, also called smart windows or switchable windows in its
application to windows or skylights, refers to electrically switchable glass or glazing which
changes light transmission properties when voltage is applied.
Certain types of smart glass can allow users to control the amount of light and heat passing
through: with the press of a button, it changes from transparent to opaque, partially blocking
light while maintaining a clear view of what lies behind the window. Another type of smart glass
can provide privacy at the turn of a switch.
Smart glass technologies are electro-chromic devices, suspended particle devices, and liquid
crystal devices.
The use of smart glass can save costs for heating, air-conditioning and lighting and avoid the cost
of installing and maintaining motorized light screens or blinds or curtains. When opaque, liquid
crystal or electro-chromic smart glass blocks most UV, thereby reducing fabric fading; for SPDtype smart glass, this is achieved when used in conjunction with low-e low emissivity coatings.
Critical aspects of smart glass include installation costs, the use of electricity, durability, as well
as functional features such as the speed of control, possibilities for dimming, and the degree of
transparency of the glass.
Electronic Paper
Electronic paper, also called e-paper or electronic ink display is a display technology designed to
mimic the appearance of ordinary ink on paper. Unlike a conventional flat panel display, which
uses a backlight to illuminate its pixels, electronic paper reflects light like ordinary paper and is
capable of holding text and images indefinitely without drawing electricity, while allowing the
image to be changed later.
To build e-paper, several different technologies exist, some using plastic substrate and
electronics so that the display is flexible. E-paper is considered more comfortable to read than
conventional displays. This is due to the stable image, which does not need to be refreshed
constantly, the wider viewing angle, and the fact that it reflects ambient light rather than emitting
its own light. An e-paper display can be read in direct sunlight without the image fading.
Lightweight and durable, e-paper can currently provide only a monochrome display, e.g., black
on white. The contrast ratio in available displays as of 2008 might be described as similar to that
of newspaper, though newly-developed implementations are slightly better. There is ongoing
competition among manufacturers to provide full-color capability.
Applications include electronic pricing labels in retail shops, and general signage, time tables at
bus stations, electronic billboards, the mobile phone Motorola FONE F3, and e-book readers
capable of displaying digital versions of books and e-paper magazines.
An organic photovoltaic cell (OPVC) is photovoltaic cell which uses organic electronic materials
for light absorption and charge transport.
Organic Solar Cell
Low cost, large scale production and flexibility of organic molecules make them appealing for
the photovoltaic applications. Molecular engineering like changing the length and functional
group of polymers can change the energy gap, which allows chemical tuning in these materials.
The optical absorption coefficient of organic molecules is high, so a large amount of light can be
absorbed with a small amount of materials. Main disadvantages associated with organic
photovoltaic cells are low efficiency, low stability and low strength compared to inorganic
photovoltaic cells.
Sources
“World Organic Electronics Market” reportlinker.com 1 April 2009
<http://www.reportlinker.com/p0119486/World-Organic-ElectronicsMarket.html?utm_source=PRNWire&utm_medium=PR&utm_campaign=PRNWire>
“Organic Electronics” wikipedia.org 22 June 2009
< http://en.wikipedia.org/wiki/Organic_electronics>
“Printed Electronics” wikipedia.org 25 June 2009
< http://en.wikipedia.org/wiki/Printed_electronics>
“Smart Windows” wikipedia.org 28 June 2009
< http://en.wikipedia.org/wiki/Smart_windows>
“Organic Solar Cell” wikipedia.org 7 July 2009
<http://en.wikipedia.org/wiki/Organic_solar_cell>
“Electronic Paper” wikipedia.org 9 July 2009
<http://en.wikipedia.org/wiki/Electronic_paper>