BASIC ELECTRONICS

(SFE 3013)

ORGANIC ELECTRONICS

PRESENTED BY :NUR FARALINA ASRAB ALI

(D20101037415)NOOR AZURAH ABDUL RAZAK

(D20101037502)SITI NORHAFIZA HAFINAS MOHD ZANUDIN

(D20101037503)WAN NORAZWANI MAHUSIN

(D20101037506)

Organic electronics, plastic electronics or polymer electronics, is a branch of electronics dealing with conductive polymers and conductive small molecules

Called as 'organic' electronics as the polymers and small molecules are carbon-based

Most polymer electronics are laminar electronics, a category that also includes transparent electronic package and paper based electronics

Conductive polymers are lighter, more flexible, and less expensive than inorganic conductors. This makes them a desirable alternative in many applications

INTRODUCTION

Historically, organic materials (or plastics) were viewed as insulators, with applications commonly seen in inactive packaging, coating, containers and so on

Research on the electrical behaviour of organic materials commenced in the 1960s

The announcement of conductive polymers in the late 1970s, and of conjugated semiconductors and photoemission polymers in the 1980s, gave new impulse to the activity in the field of organic electronics

Polyacetylene was one of the first polymers reported to be capable of conducting electricity, and it was discovered that oxidative doping with iodine causes the conductivity to increase by 12 orders of magnitude

HISTORY

This discovery and the development of highly-conductive organic polymers was credited to Alan J.Heeger, Alan G. MacDiarmid, and Hideki Shirakawa, who were jointly awarded the Nobel Prize in Chemistry in 2000 for their 1977 discovery and development of oxidized, iodine-doped polyacetylene

Ching W. Tang -who built the first organic light-emitting diode (OLED) and organic photovoltaic cell is widely considered the father of organic electronics

Alan J.HeegerBorn : January 22, 1936 (age 76), Sioux City, Iowa, USA Nationality : United StatesFields : Physics, Chemistry Institutions : University of Pennsylvania University of California, Santa Barbara Notable awards : Nobel Prize in Chemistry Balzan Prize ENI award

Alan MacDiarmid

Born : 14 April 1927 at Masterton, New Zealand Died :7 February 2007 (aged 79) Drexel Hill, Pennsylvania Institutions : University of Pennsylvania, University of St Andrews, University of Texas at Dallas Notable awards : - The Francis J. Clamer Medal in 1993 - Nobel Prize for Chemistry in 2000

HIDEKI SHIRAKAWA

Born in Tokyo, Japan

Institution : University of Pennsylvania andUniversity of Tsukuba

Notable awards : Noble Prize for Chemistry in 2000

OLED (organic

light-emitting diode)

LED in which the emissive

electroluminescent layer is a film of organic

compound which emits

light in response to an electric current

This layer of organic

semiconductor material is situated

between two electrodes.

Generally, at least one of

these electrodes is transparent

2 main families of OLEDs :

- those based on small

molecules -those

employing polymers

Have large conjugated

systems which are formed by

chemical reactions of

hydrocarbons

Some photovoltaic

cells can also convert infrared

(IR) or ultraviolet (UV) radiation into

DC

Organic transistors with several tens of nanometers-thick organic semiconductors are called "organic thin-film transistors" (OTFT)

Conventional inorganic transistors require high temperatures (500-1,000ºC), but organic transistors can be made between room temperature and 200ºC.

Organic transistors can even be formed even on a plastic substrate, which is vulnerable to heat. Therefore organic transistors enable to realize not only light and thin, but also flexible device elements, allowing them to be used in a variety of unique devices

Materials

Organic Light-Emitting

There wide selection of OLED materialsOLED materials consist of:

1. Electron Transport 2. Host Transport3. Polymer Hole Transport4. Emitter/Dopant5. Synthetic Intermediates

Sub materials that contain in each material may different or may be same.

For Electron Transistor, it contain of :

In Host Transport, it contain of :

While Polymer Transport/ Host contain:

Emitter dopant

Synthetic Intermediates

Organic Photovoltaic There are a lot of material consist in organic

photovoltaic such as:

1. [6,6]-Phenyl C61 butyric acid methyl ester2. [6,6]-Pentadeuterophenyl C61 butyric acid methyl

ester3. [6,6]-Phenyl-C61 butyric acid butyl ester 4. [6,6]-Phenyl-C61 butyric acid octyl ester5. [60]ThPCBM 6. (6,6)-Phenyl C71 butyric acid methyl ester7. (6,6)-Phenyl C85 butyric acid methyl ester 8. Poly[2-methoxy-5-(3’,7’-dimethyloctyloxy)1,4-

phenylenevinylene] 9. Poly[2-methoxy-5-(2-ethylhexyloxy)

1,4phenylenevinylene]10.Poly(3-hexylthiophene-2,5-diyl)

Structure of the material in organic photovoltaic:

1. [6,6]-Phenyl C61 butyric acid methyl ester

2. [6,6]-Pentadeuterophenyl C61 butyric acid methyl ester

3. [6,6]-Phenyl-C61 butyric acid butyl ester

4. [6,6]-Phenyl-C61 butyric acid octyl ester

5. [60]ThPCBM

6. (6,6)-Phenyl C71 butyric acid methyl ester

7. (6,6)-Phenyl C85 butyric acid methyl ester

8. Poly[2-methoxy-5-(3’,7’-dimethyloctyloxy)1,4-phenylenevinylene]

9. Poly[2-methoxy-5-(2-ethylhexyloxy) 1,4phenylenevinylene]

10. Poly(3-hexylthiophene-2,5-diyl)

Organic Materials for Thin Film Transistors

To make OTFTs, materials ranging from conductors (for electrodes),

semiconductors (for active channel materials), to

insulators (for gate dielectric layers) are needed.

Semiconductors

Two types of organic semiconductors: p-type (holes as major charge carriers) and n-type

(electrons as major charge carriers).

 The organic semiconductor layer usually consists of π-conjugated oligomers or polymers, in which the π–π

stacking direction should ideally be along the current flow direction.

This requires the semiconductor molecules to self-assemble into a certain orientation upon either vapour

or solution deposition. It is also important that the semiconductor thin film has large, densely packed and well-interconnected grains. Most small molecule, high performance organic semiconductors tend to have the long axes of the molecules oriented close to normal to the dielectric surface with the typical grain size in the

order of at least a few micrometres.

Dielectric

The dielectric layer for organic transistors should be as thin as possible, pinhole-free, and ideally with a high dielectric constant for low voltage

operation. Inorganic, organic, and inorganic/organic hybrid materials have been investigated as the gate dielectric materials.

Promising materials include poly(methy methacrylate) (PMMA), poly(styrene), poly(vinyl

phenol), silsesquioxane (glass resin), and benzocyclobutene (BCB), etc.

Electrode

•For organic transistors to function properly, charge injection from the electrode needs to be efficient. This requires the work function of the electrode to match well with the energy level of the organic semiconductor such that the energy barrier for charge injection is low.

•Typically high work function electrodes (Au, Pd, or indium tin oxide) have been used for p-channel organic transistors. Electrode surface modification with a self-assembled monolayer can be used to improve the charge injection into the organic semiconductor.

• When the organic semiconductor is deposited onto the source and drain electrodes, the morphology of organic semiconductors is significantly different when deposited on SAM-modified Au compared to bare Au.

• This observation has been used to tune the morphology of the organic semiconductor at the Au/ organic interface to improve its charge injection

Reel-to-reel vacuum metallization

Vacuum metallization is the process of coating a

substrate with a thin metal layer under high-vacuum

condition

Requirement in development of the metallization

The coating of web materials are referred to as vacuum web coating

Requirement In Development Of The Metallization

• Higher conductivity• Smooth surfaces• Fewer defects in the metal layer• Improved barrier propertiesHigher quality

•Greater reel length / diameter•Greater web width•Higher web speed•Shorter downtime

Lower cost

The Metallization Process

• Evaporation of pure metal layers from the vapor phase requires high-vacuum conditions (pressure <5X10^-4mbar)

• Good vacuum condition : the entire to be coated reel must be placed inside the vacuum chamber. (volume for vacuum chamber 15-20m^3)

• To minimize downtime, vacuum condition is ideal and constant

• Reaction between metal and oxygen/water vapor from residual gas cause contamination of the evaporated layer, resulting in poor brilliance, lack of metallic character, poor barrier, poor adhesion, and high electrical resistance of the metal layer.

Evaporation sources• Resistance evaporator known as boats• A wire is brought into contact with each

boats which it instantly melt and become gaseous.

• The metal vapour condense on cooled film and form a thin metal coating on the film surface.

Thermal Evaporation

• Higher evaporation temperatures than resistance evaporator

• Disadvantage: complex instrumentation required

E-beam Evaporation

• Metal atoms are removed from a solid target by means of ion bombardment

• Then absorbed on the substrate surface facing the target

Sputtering

The Metallization Step1. Loading of the nonmetallized reel into the winding

chamber2. Closing and evacuation of the chamber3. Heating of the boats4. Unwinding of the reel5. Opening the aperture above the boats6. Metallization of the film reel7. Cooling of the boats8. Venting of the chamber9. Opening of the chamber and removing the metalized

film reel10.Cleaning of the chamber

•OVPD was invented by S.Forrest at Princeton University•Has potential to overcome the limitation of VTE •The arrangement of evaporation and condensation is decoupled

Principle of OVPD

1. Evaporation of the organic material occurs in individual and decoupled quartz pipes.

2. A precise amount of carrier gas is added into each quartz pipe by MFC to pick up organic molecules.

3. Then it’s transported into hot wall deposition chamber

4. They (ex: host and dopant) mix and evaporate.5. They diffuse through the boundary layer on to the

cooled substrate

OVPD Process Properties VTE

10^-3 -10 Torr Pressure <10^-6 Torr

(~1%) Layer uniformity (~3%)

<0.5% Doping control >2.0%

Low Cross contamination

High

~5-10Å Thickness control ~5-10Å

50-70% Deposition efficiency

<15%

Low because of hot wall design

System downtime High because of particle generation

APPLICATION OF ORGANIC ELECTRONICS

Best of amazing organic electronics HD - YouTube.flv

• Our daily activities nowadays are mainly supported by machine and electronic devices based on silicon chip technology.

• Consumers demand small size devices at very low price. However, the technology to shrink the size of silicon chip will reach its limitation, besides the cost of building a chip manufacturing plant doubles every 36 months.

• As an alternative to obtain low cost small size devices, some scientists look at utilizing organic thin films.

Using Organic Transistors-Flexible Displays

• Displays play an important role in the interaction between human beings and information.

• Organic materials are used in the display mechanisms of today's LCD and OLED displays, but their control systems consist of inorganic transistors on glass substrates (silicon TFT).

• This type of display is difficult to bend. However, a display with organic transistors on a plastic substrate would be completely flexible. Such a display could also be dropped without breaking, rolled up, or folded

Organic Solar Cells (OSCs)• (OSCs) have long been a promising alternative to

conventional solar cells, but their low efficiency, low stability, and low strength

• The most common and promising application of Organic Photovoltaic cells are in organic solar cells. Because of the lower costs with printed photovoltaic, there is great potential of installing organic solar panels at any location, including stand-alone power stations and on buildings or roads, for developing countries and rural areas, where electrical infrastructure lacks.

• An (OSCs) that generates a sufficiently high voltage to recharge a lithium-ion battery

• OSCs are based on organic conductors and semiconductors which can be applied from the liquid phase by techniques like spincoating or inkjet printing.

• Portable electronic devices such as e-book readers, cameras and some mobile phones could soon be recharged on the move in low light levels and with partial shading.

Organic Light Emitting Diodes (OLEDs)

• Visible light emission can be stimulated by applying a voltage to a thin layer of an organic semiconductor.

• The light emitted provides a window on the physics of the material, enabling us to learn about the nature of the excited states in the material.

• It is also useful for information display, lighting, and even for the treatment of skin cancer.

• light-emitting organic semiconductor could be used for high efficiency lighting, thereby reducing energy consumption.

• 55-inch television set from the South Korean electronics giant is just four millimeters thick and using the display technology of organic light emitting diodes (OLED).

• OLED televisions do not require back lighting and feature better color contrast than normal LED flat panel televisions.

Active-matrix organic light-emitting diode (AMOLED)

• A display technology for use in mobile devices and televisions. OLED describes a specific type of thin-film display technology in which organic compounds form the electroluminescent material, and active matrix refers to the technology behind the addressing of pixels.

• As of 2012, AMOLED technology is used in mobile phones, media players and digital cameras

• Samsung has marketed their version of this technology as Super AMOLED

Future of Organic Electronic

Smart Textiles • Interactive textiles or so-called smart fabric products are

reaching the market for healthcare/medical, public safety, military, and sporting applications. These products will be designed to monitor the wearer's physical well being and vital signs such as heart rate, temperature, and caloric consumption, among many others.

• Smart fabrics are driven by technological improvements and increasing reliance on MEM’s based integrated sensors. Development of flexible displays comprised of OLED technologies will be integrated into clothing solutions, providing the ability to view information in real-time via wireless communications.

Skin Cancer Treatment:– team of researchers in Scotland has demonstrated

in a pilot study that OLEDs may one day change the way photodynamic therapy (PDT) is used to treat skin cancer.

– In addition to the treatment of skin cancers, the researchers believe the technology could also be used in the cosmetic industry for anti-aging treatments or skin conditions such as acne.

Portable Compact Screens• Screens that can roll up into

small devices• Black and White prototype

already made by Philips(the Readius™ at the bottom-left)

Lab on a chip:• A device that incorporates

multiple laboratory functions in a single chip

• Organic is replacing some Si fabrication methods:

-Lower cost -Easier to manufacture -More flexible

Advantages of Organic Electronics

While silicon processing requires temperatures above 1000 °C and clean room conditions, "plastic

electronics" merely require room temperature.

In contrast to the current time-consuming and thus

expensive technology, organic semiconductors can be mass-produced at a low

cost.

the manufacturing methods are

environmentally friendly and save

resources

easily and flexibly adapt to surfaces, requiring only little

space, and are virtually unbreakable

Disadvantages of Organic Electronics

• Conductive polymers have high resistance and therefore are not good conductors of electricity.

• Because of poor electronic behavior (lower mobility), they have much smaller bandwidths.

• Shorter lifetimes and are much more dependant on stable environment conditions than inorganic electronics would be.

CONCLUSION

• With the consistent refinement of organic electronics, numerous application possibilities for everyday use will arise.

• For example, one could think of illuminated wallpapers for room lighting or as a variant with an imprinted TV.

• Windows made of transparent solar cells could provide houses with energy. Screens and laptops could be printed and rolled.

• There are hardly any limits to the imagination.

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Deepak Gupta. Organic Electronics II. .Retrieved on December 2, 2012 from http://www.iitk.ac.in/directions/directions_dec07/3jan~DEEPAK.pdf

Ilya Koltover (2007). Materials matter. Retrieved on December 1, 2012 from http://www.sigmaaldrich.com/content/dam/sigma-aldrich/materials-science/material-matters/material_matters_v2n3.pdf

J. M. Shaw, P. F. Seidler. Retrieved on December 2, 2012 from http://www.depeca.uah.es/depeca/repositorio/asignaturas/32305/shaw.pdf

Roland Ghim Siong Goh (August 2008). Carbon nantube for organic electronics. Retrieved on December 1, 2012 from http://eprints.qut.edu.au/20849/1/Roland_Goh_Thesis.pdf

Ossila - enabling organic electronics. Retrieved on December 2, 2012 from http://www.ossila.com/