transparent electronics_seminar.docx

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TRANSPARENT ELECTRONICS

by

Aakash Kumar VarmaE.C.E. (3rd year)

Roll No.: 0905232001

Submitted to the

Department of Electronics and Communication Engineering

in partial fulfillment of the requirements

for the degree of

Bachelor of Technologyin

Electronics and communication Engineering

Institute of Engineering and Technology, Lucknow

Gautam Buddh Technical University

(April, 2012)

Student Name: Seminar Guide Name:

Aakash Kumar Varma Er. Deepali Srivastava

Student Signature: Seminar Guide Signature:


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Department of Electronics Engineering

INSTITUTE OF ENGINEERING & TECHNOLOGY

SITAPUR ROAD, LUCKNOW

CERTIFICATE

This is to certify that seminar report entitled TRANSPARENT

ELECTRONICS being submitted by Mr. Aakash Kumar Varma of

3rd year (Electronics and Communication Engineering), under theguidance ofEr. Deepali Srivastava (Seminar Incharge).

Er. Deepali Srivastava Prof. Neelam Srivastava

(Seminar Incharge) (Head of Department)


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ACKNOWLEDGEMENT

It gives me a great sense of pleasure to present the B.Tech. seminar report

undertaken during B. Tech. 3rd

Year. I owe special debt of gratitude to respectedDeepali Srivastava Maamfor her constant support and guidance throughout the

course of my work. Her sincerity, thoroughness and perseverance have been a

constant source of inspiration for me. It is only her cognizant efforts that mine

endeavor have seen light of the day.

I am very grateful to Prof. Neelam Srivastava, Head of the Department, for

giving me a chance to present this seminar.

I also do not like to miss the opportunity to acknowledge the contribution

of all dignitary Staff-members of I.E.T. Lucknow for their kind assistance andcooperation during the development of my Seminar report. Last but not the least, I

acknowledge my friends for their contribution in the completion of the seminarreport.

Apart from the efforts of me, the success of this project depends largely on

the encouragement and guidelines of many others. I take this opportunity toexpress my gratitude to the people who have been instrumental in the successful

completion of this report.

Aakash Kumar VarmaB.Tech.

E.C.E.- 3rd year

Roll No. - 0905232001


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TABLE OF CONTENTS

Chapter 1 Introduction 5

Chapter 2 Pre- History 7

2.1. Transparent Conductive Oxides (TCOs) 7

2.2. Thin-Film Transistors (TFTs) 7

Chapter 3 How transparent electronics devices work? 9

3.1 Oxides play key role 11

Chapter 4 Advancements made in Transparent Electronics 13

Chapter 5 Applications of Transparent Electronics 18

5.1 Imaginative Examples of use of Transparent Electronics 19

Chapter 6 Market of Transparent Electronics 20

6.1 Three Factors That Can Lead to the Commercial 22

Awakening of Transparent Electronics

6.1.1 Aesthetics 22

6.1.2 Integration 22

6.1.3 Improved Economics 23

6.1.4 Non-transparent aspects of transparent materials 23

Chapter 7 Future Scope 24

Chapter 8 Conclusion 25

Chapter 9 References 26


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LIST OF FIGURES, TABLES AND GRAPHS

Fig 1.1 Transparent Computer (Artists Imagination) 5

Fig 1.2 Transparent iPhone 6

Table 2.1 Electrical properties of common transparent conducting 7

oxides (TCOs).

Fig 2.1 Fabrication of a bottom-gate TFT with a SnO2 channel layer. 8

Fig 2.2 Structure of layered TFT 8

Fig 3.1 Typical ZnO-TFT characteristics 10

Fig 3.2 Development of ZnO and a-IGZO Semiconductors 11

Fig 3.3 Graph showing variation of transmittance and wavelength of 12

Substrate.

Fig 4.1 Characteristics other than Transparency. 14

Fig 4.2 Fabrication of fully transparent aligned SWNT transistors. 15

Fig 4.3 Generation of Transparent Electronics 16

Fig 5.1 Examples of Transparent Electronics Devices (Illustrative) 19

Fig 6.1 Forecast of Transparent Electronics Products by Application 20

Fig 7.1Graphene is transparent and can be used as material. 24

Fig 8.1 Usage of Transparent Electronics devices in future 25


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Chapter-1

INTRODUCTION

Transparent electronics (also called as invisible electronics) is an emergingtechnology that employs wide band-gap semiconductors for the realization of

invisible circuits. This monograph provides the first roadmap for transparentelectronics, identifying where the field is, where it is going, and what needs to

happen to move it forward. Although the central focus of this monograph involvestransparent electronics, many of the materials, devices, circuits, and process-

integration strategies discussed herein will be of great interest to researchersworking in other emerging fields of optoelectronics and electronics involving

printing, large areas, low cost, flexibility, wearability, and fashion and design.

Fig 1.1 Transparent Computer (Artists Imagination)

Transparent electronics is an emerging science and technology field focused

on producing invisible electronic circuitry and opto-electronic devices.Applications include consumer electronics, new energy sources, and

transportation; for example, automobile windshields could transmit visualinformation to the driver. Glass in almost any setting could also double as an

electronic device, possibly improving security systems or offering transparentdisplays. In a similar vein, windows could be used to produce electrical power.

Other civilian and military applications in this research field include real time


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wearable displays. As for conventional Si/IIIV-based electronics, the basic device

structure is based on semiconductor junctions and transistors. However, the devicebuilding block materials, the semiconductor, the electric contacts, and the

dielectric/passivation layers, must now be transparent in the visible a true

challenge! Therefore, the first scientific goal of this technology must be todiscover, understand, and implement transparent high-performance electronic

materials. The second goal is their implementation and evaluation in transistor andcircuit structures. The third goal relates to achieving application-specific properties

since transistor performance and materials property requirements vary, dependingon the final product device specifications. Consequently, to enable this

revolutionary technology requires bringing together expertise from various pure

and applied sciences, including materials science, chemistry, physics,electrical/electronic/circuit engineering, and display science.

During the past 10 years, the classes ofmaterials available for transparent electronics

applications have grown dramatically. Historically,this area was dominated by transparent conducting

oxides (oxide materials that are both electricallyconductive and optically transparent) because of

their wide use in antistatic coatings, touch displaypanels, solar cells, flat panel displays, heaters,

defrosters, smart windows and optical coatings.

Fig 1.2 Transparent iPhoneAll these applications use transparent conductive oxides as passive

electrical or optical coatings. Oxide semiconductors are very interesting materialsbecause they combine simultaneously high/low conductivity with high visual

transparency. The field of transparent conducting oxide (TCO) materials has beenreviewed and many treatises on the topic are available. However, more recently

there have been tremendous efforts to develop new active materials for functionaltransparent electronics. These new technologies will require new materials sets, in

addition to the TCO component, including conducting, dielectric andsemiconducting materials, as well as passive components for full device

fabrication.


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Chapter-2

PRE- HISTORYThe two technologies which preceded and underlie transparent electronics

are Transparent Conductive Oxides (TCOs) and Thin- Film Transistors (TFTs).

2.1 Transparent Conductive Oxides (TCOs)

TCOs constitute an unusual class of materials possessing two physical

properties- high optical transparency and high electrical conductivity. They are

generally considered to be mutually exclusive (Hartnagel et al 1995). This peculiar

combination of physical properties is only achievable if a material has a

sufficiently large energy band gap so that it is non-absorbing or transparent or

transparent to visible light, i.e., > ~3.1 eV and also possesses a high enough

concentration > ~1019 cm-3, with a sufficiently large mobility > ~1 cm2V-1s-1, that the

material can be considered to be a good conductor of electricity.

The three most common TCOs are indium oxide In2O3, tin oxide SnO2 and

zinc oxide ZnO2. All these materials have band gaps above that required for

transparency across the full visible spectrum.

Table 2.1 Electrical properties of common transparentconducting oxides (TCOs). Conductivities reported are for best-

case polycrystalline films

Materi

al

Bandga

p

(eV)

Conductivity

(Scm-1

)

Electron

Concentratio

n (cm-3

)

Mobility

(cm2V-1s-1)

In2O3 3.75 10,000 >1021 35

ZnO2 3.35 8,000 >1021 20

SnO2 3.6 5,000 >1020 15

2.2 Thin-Film Transistors (TFTs)

The thin-film transistor is another technology underlying transparent

electronics, since it is a bridge between passive electrical and active electronic

applications. Although TFTs were the subject of the earliest transistor patents, the


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first realization of a TFT was reported in 1961 by Weimer and fabricated via

vacuum evaporation using CdS as a channel layer. None of these undertakings

involved an attempt to realize a fully transparent TFT.

Fig 2.1 Fabrication of a bottom-gate TFT with a SnO2 channel layer.

(a) Photo-resist is patterned by bottom exposure, using the aluminum

gate as a mask. (b) After photo resist development, a metal blanket

coating is evaporated. (c) Final TFT device structure after lift-off.

Fig 2.2 Structure of layered TFT


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Chapter-3

HOW TRANSPARENT ELECTRONIC

DEVICES WORK?The challenge for producing "invisible" electronic circuitry and opto-

electronic devices is that the transistor materials must be transparent to visible light

yet have good carrier mobilities. This requires a special class of materials having

"contra-indicated properties" because from the band structure point of view, the

combination of transparency and conductivity is contradictory.

Transparent electronics are nowadays an emerging technology for the next

generation of optoelectronic devices. Oxide semiconductors are very interestingmaterials because they combine simultaneously high/low conductivity with high

visual transparency and have been widely used in a variety of applications (e.g.

antistatic coatings, touch display panels, solar cells, flat panel displays, heaters,

defrosters, optical coatings, among others) for more than a half-century.

Transparent oxide semiconductor based transistors have recently been

proposed using as active channel intrinsic zinc oxide (ZnO). The main advantage

of using ZnO deals with the fact that it is possible to growth at/near room

temperature high quality polycrystalline ZnO, which is a particular advantage for

electronic drivers, where the response speed is of major importance. Besides that,

since ZnO is a wide band gap material (3.4 eV), it is transparent in the visible

region of the spectra and therefore, also less light sensitive.

Transparent oxide semiconductor based transistors have recently been

proposed using as active channel intrinsic zinc oxide (ZnO). The main advantage

of using ZnO deals with the fact that it is possible to growth at/near room

temperature high quality polycrystalline ZnO, which is a particular advantage forelectronic drivers, where the response speed is of major importance. Besides that,

since ZnO is a wide band gap material (3.4 eV), it is transparent in the visible

region of the spectra and therefore, also less light sensitive.


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(a)

(b)

Fig 3.1 Typical ZnO-TFT characteristics (a) transfer and (b) output

characteristics, with the channel layer deposited at room temperature by rf

magnetron sputtering produced at FCT-UNL.


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3.1 Oxides Play Key Role:

One major reason why there has been such interest and activity in

transparent electronics recently is that there has been a sharp jump in the carrier

mobility of transparent semiconductors, which determines transparent TFTcharacteristics. This now exceeds the carrier mobility of materials such as low-

temperature poly-Si (LTPS) and amorphous Si used in LCD panels.

Fig 3.2 Development of ZnO and a-IGZO Semiconductors Takes Off

Researchers have been interested in ZnO and InGaZnO4 (a-IGZO)transparent amorphous oxide semiconductors in the last few years. Carrier

mobility of ZnO transistors was 7cm2/Vs in 2003, rising to 70 cm2/Vs in 2006,

and to 250 cm2/Vs in 2007. Several manufacturers have plans to use a-IGZO

in products. While there are remaining problems, transparent oxide p-type

semiconductors have also been in development.

Even better, it means lower cost. Transparent semiconductors such as GaN

and diamond are already known, but they come at high cost (materials,

manufacturing, etc) which makes them impossible to use in transparent electronic

devices demanding relatively large screens, such as displays. The candidate

materials attracting the most interest can be broadly divided into two oxide

categories. The first group is zinc oxide (ZnO), and the second is amorphous

oxides with heavy metal content, such as amorphous InGaZnO4 (a-IGZO). Both


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pass visible light and are almost completely transparent. The carrier mobility of a

TFT made with ZnO is 250cm2/Vs, significantly higher than the 100cm2/Vs

achieved by LTPS. A TFT made with a-IGZO ranges from 1cm2/Vs to

100cm2/Vs, again significantly higher than the 1cm2/Vs max that amorphous Si

provides. The pace of R&D has been accelerating in the last few years, withgrowth in ZnO carrier mobility especially rapid and manufacturers actively

developing applications based on a-IGZO. Announcements like that of LG

Electronics at E-MRS 2007 are based on a-IGZO.

A comparison of ZnO and a-IGZO shows that ZnO has the lead when it

comes to carrier mobility. At present, though, a-IGZO is the material of choice for

large-area displays, electronic paper utilizing low-temperature processing, etc.

There are even some organic transparent semiconductor materials, but even the

best only achieve a carrier mobility of around 5cm2/Vs. Organic semiconductors

are therefore limited to applications with larger area where the lower cost can be

leveraged.

Fig 3.3 Graph showing variation of transmittance (denoting

reflection) and wavelength of Substrate.


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Chapter-4

ADVANCEMENTS MADE IN

TRANSPARENT ELECTRONICS

Significant advances in the emerging science of transparent electronics,

creating transparent "p-type" semiconductors that have more than 200 times the

conductivity of the best materials available for that purpose a few years ago. This

basic research is opening the door to new types of electronic circuits that, when

deposited onto glass, are literally invisible. The studies are so cutting edge that the

products which could emerge from them haven't yet been invented, although they

may find applications in everything from flat-panel displays to automobiles or

invisible circuits on visors.

Most materials used to conduct electricity are opaque, but some invisible

conductors of electricity are already in fairly common use, the scientists said. More

complex types of transparent electronic devices, however, are a far different

challenge - they require the conduction of electricity via both electrons and

"holes," which are positively charged entities that can be thought of as missing

electrons.

These "p-type" materials will be necessary for the diodes and transistors that

are essential to more complex electronic devices. Only a few laboratories in the

world are working in this area, mostly in Japan, the OSU scientists. As recently as

1997, the best transparent p-type transparent conductive materials could only

conduct one Siemens/cm, which is a measure of electrical conductivity. The most

sophisticated materials recently developed at OSU now conduct 220 Siemens/cm.

These are all copper oxide-based compounds that we're working with. Rightnow copper chromium oxide is the most successful. Researchers continue to work

with these materials to achieve higher transparency and even greater conductivity.


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Fig 4.1 Characteristics other than Transparency. Transparent

semiconductors, inaddition to being transparent, have a number of useful

characteristics, including a wide band gap, relatively high carrier mobility,

low-temperature manufacturability, and low manufacturing costs thanks to

the low-temperature process and inexpensive materials. As a result, R&D intoproperties other than transparency is also active.

Researchers at Oregon State University and Hewlett Packard have

reported their first example of an entirely new class of materials which could be

used to make transparent transistors that are inexpensive, stable, and

environmentally benign. This could lead to new industries and a broad range of

new consumer products, scientists say. The possibilities include electronic

devices produced so cheaply they could almost be one-time "throw away"

products, better large-area electronics such as flat panel screens or flexibleelectronics that could be folded up for ease of transport. Findings about this new

class of "thin-film" materials, which are called amorphous heavy-metal cation

multi component oxides, were just published in a professional journal, Applied

Physics Letters. The research was funded by the National Science Foundation and

Army Research Office.

This is a significant breakthrough in the emerging field of transparent

electronics, experts say. The new transistors are not only transparent, but they work

extremely well and could have other advantages that will help them transcend

carbon-based transistor materials, such as organics and polymers, that have been

the focus of hundreds of millions of dollars of research around the world.


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Fig 4.2 Fabrication of fully transparent aligned SWNT transistors. (a)

Schematic diagram of aligned SWNT transfer and a device structure

consisting of a substrate (glass or PET), ITO as back gate, SU8 as dielectric,

aligned SWNTs as channel, and ITO as source and drain. (b) SEM image oftransferred aligned SWNTs on SU8 on a glass substrate. (c) SEM image of

devices showing the ITO source and drain electrodes fabricated on glass.

Inset: SEM image of aligned nanotubes bridging ITO electrodes. (d) Optical

micrograph of fully transparent aligned SWNT transistors on a 4 in. glass

wafer. (e) Optical micrograph of fully transparent aligned SWNT transistors

on a PET sheet of 3 in. - 4 in.


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"Compared to organic or polymer transistor materials, these new inorganic

oxides have higher mobility, better chemical stability, ease of manufacture, and are

physically more robust," said John Wager, a professor of electrical and computer

engineering at OSU. "Oxide-based transistors in many respects are already further

along than organics or polymers are after many years of research, and this mayblow some of them right out of the water."

"Frankly, until now no one ever believed we could get this type of electronic

performance out of transparent oxide transistors processed at low temperatures,"

Wager said. "They may be so effective that there will be many uses which don't

even require transparency, they are just a better type of transistor, cheap and easy

to produce."

Fig 4.3 Generation of Transparent Electronics

The newest devices are zinc-tin-oxide thin film transistors, according tocollaborating researchers in the OSU College of Engineering, OSU College of

Science and at Hewlett Packard. They are an evolution of zinc oxide transistors,

which gained attention as the world's first see-through transistor when OSU

scientists announced their discovery last year. But this new material combines the

characteristics of different elements to give levels of electronic performance and


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"mobility" in electronics, an observation about how fast electrons can move

within a materialthat are an order of magnitude faster than the earlier transparent

transistors, Wager said.

They are amorphous, meaning they have no long range crystalline order,which helps to keep processing costs a great deal lower. They are also physically

robusthard to scratch, chemically stable, resist etching, and have a very smooth

surface. They are made from low cost, readily-available elements such as zinc and

tin, which raise no environmental concerns.

From material and design advancements to new innovative processing

methods, there have been significant recent achievements in the area of transparent

electronics. Materials & Performance advancements in transparent wide band gap

electronic materials are described in the articles reporting on metal oxide, GaN,and rare earth systems. Material enhancements focusing on lowering resistivity and

increasing mobility are described. Attention is given to both experimental and

modeling and simulation efforts. These papers discuss measured material

properties, modeling results, and performance of structures up to the complexity of

TFTs. Along with material progress; advancements in Fabrication Techniques are

required to enable new device designs and new applications. The full benefits of

transparent electronics are seen in the final device design and performance.

Transparent electronics enable advancements in device technologies and open theopportunity for new applications. Application articles focused on the benefits of

transparent electronics include display and organic light-emitting diode devices.


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Chapter-5

APPLICATIONS OF

TRANSPARENT ELECTRONICSAs the oxide semiconductors are wide band gap materials, transparent TFTs can be

easily realized by the combination of transparent electrodes and insulators.

Transparency is one of the most significant features of TAOS TFTs. As the band

gap of a-Si is 1.7 eV and that of crystalline-Si is 1.1 eV, transparent electronics

cannot be realized in Si technology. In TAOS TFTs, features of high mobility or

low process temperature have attracted a lot of attention. However, transparency

has been underestimated or even neglected in the research and development of

TAOSs. Few examples of actual applications have been reported exploiting the

transparency of TAOSs until now [25, 26]. Transparent circuits will have

unprecedented applications in flat panel displays and other electronic devices, such

as see through display or novel display structures. Here, practical examples taking

advantage of the transparency of TAOS TFTs are: Reversible Display, Front

Drive Structure for Color Electronic Paper, Color Microencapsulated

Electrophoretic Display, and Novel Display Structure Front Drive Structure.

Indium oxide nanowire mesh as well as indium oxide thin films were used to

detect different chemicals, including CWA simulants.

They have been widely used in a variety of applications like:1. Antistatic coatings

2. Touch display panels3. Solar cells,

4. Flat panel displays5. Heaters

6. Defrosters

7. Optical coatings etc


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5.1 Imaginative Examples of use of Transparent Electronics

You are travelling in a car and you want to watch a movie or video play.

Now the glass shields i.e. window panels will turn into a television screen and this

is possible with this technology. This is helpful when the driver can't take away hiseyes from road but still want to watch out a map of route. Then front window panel

acts display with the help of this tech.

Fig 5.1 Examples of Transparent Electronics Devices (Illustrative)


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Chapter-6

MARKET OF TRANSPARENT

ELECTRONICSEventually the materials suite used by transparent electronics will stabilize

and the role of organic electronics materials and nanomaterials in transparent

electronics will become clearer. But as we have explained above, the possible

technical directions that these materials are likely to take are fairly well defined;

although we should not exclude surprises entirely.

Fig 6.1 Forecast of Transparent Electronics Products by Application

Opportunities in the area of the transparent electronics products themselvescan be somewhat difficult to pick out. This is not just because of the diversity of

the possible products that can be built within the context of transparent electronics

paradigm, but also because both the actual past of transparent electronics so far and

the somewhat futuristic prognostications about transparent electronics that have


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been widely published are a distraction from understanding what can really be

achieved in the next few years with transparent electronics:

Too cool to succeed: Transparent electronics suffers, we believe, from the

fact that it is so cool that it virtually cries out to be built into highly futuristicscenarios. And this is exactly what has happened. Just a casual look at the literature

on transparent electronicseven the formal technical literatureusually reveals

quite quickly a slew of references to science fiction movies in which transparent

electronics are featured. The favorite in this regard is the Tom Cruise movie

Minority Report, but other movies are also referenced. This is all a lot of fun, but

gives a false impression of the current state of the art in transparent electronics and

what might be achieved using this technology. Watching Cruise in Minority

Report, it is never quite clear just why he is using transparent displays in his work.

In other words, these display are props not just in the sense that they are not

physically real (they dont actually function). They are also divorced from market

realities.

Current apps for transparent electronics are quite primitive:

Paradoxically, the other reason why systems opportunities in the transparent

electronics space can be difficult to identify is the exact opposite of the over-

optimism reported on in the previous bullet point. A quick examination of the

current offerings that might reasonably be included under the heading oftransparent electronics reveals not products that, with a little tinkering could

make it into Minority Report II, as it were, but rather primitive niche products.

For example, in the display space, if one looks for transparent displays, what

one will find are simple passive matrix LED and EL displays which represent a

tiny niche within the digital signage business; they are displays with very limited

functionality. Similarly, self-tinting smart windows have been around long enough

to show that they cannot compete with a conventional window, when a customer is

looking for something that enables good natural lighting and attractive views. Orwhere tinting is critical to the specific application, the difference between tinted

and untinted offered by a smart window is just not great enough. Again, we are

looking at products and concepts that are out of tune with market realities.


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6.1 Three Factors That Can Lead to the Commercial Awakening of

Transparent Electronics

Given all this, the big question is can transparent electronics move beyond

the fanciful on the one hand and low-performing niche products on the other? Inour view, there are four critical aspects of transparency that the design and

marketing of transparent electronics products needs to focus on for it to become a

serious revenue earner. These factors are (1) aesthetics, (2) integration (3)

improved economics and (4) (somewhat paradoxically), aspects of transparent

materials that are not directly related to transparency:

Other relevant drivers for transparent electronics may be discovered over

time, but these are the ones that seem to matter now.

As the transparent electronics materials suite that we discussed earlier

improves, it seems reasonable to expect an increased ability of transparent

electronics to compete over all and any of the three dimensions mentioned above.

6.1.1 Aesthetics

It is intrinsically hard to measure the impact of aesthetics on market

response, but important to remember that aesthetics has always been a key factor in

marketing glass products; the glass industry having a considerably longer history

and deeper understanding of marketing transparent products than the emerging

transparent electronics industry.

Aesthetics seems to be key too much of the transparent electronics that has

appeared to date. The simple transparent displays that is already available for use

in advertising use transparency to gain extra attention. And transparent solar

panels are being deployed in part because they look better than large framed solar

panels installed in an all-too-visible fashion on a roof.

6.1.2 Integration

Because transparency enables visual access to multiple layers of a large-area

panel it permits an additional level of integration. This is most obvious in the

transparent overlay displays that are already being built in prototype by the display


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industry; but it is also part of the design story in the smart-window concepts that

are being dreamed up that combine self-tinting windows, OLEDs and PV.

6.1.3 Improved economics

Obviously, in the end all of the advantages attributable to PV reduce to

improved economics, but in some cases this is more obviously the case. One

example of that is in the PV space again, where transparent solar panels represent

an example of building integrated PV in which the cost of building materials and

of PV can be distributed over a common substrate, thereby reducing total

expenditures.

6.1.4 Non-transparent aspects of transparent materials

As mentioned above, in the case of transparent conductors, some transparentelectronic materials have been developed without truly transparent electronics in

mind as an application. However, it is possible that the converse could be true as

well; that is that materials that are developed specifically with transparent

electronics in mind could find a larger market.

The primary exampleperhaps the only example, so farof this kind of thing

relates to the oxide TFTs that are being developed with transparent display

backplanes in mind. There is also serious consideration being given to the

possibility that these TFTs could be used in OLED displays more generallythat

is, in non-transparent OLED displayson price and performance grounds

Obviously, the business potential for transparent electronics is limited if all the

work and all the press releases concerned just materials and research devices. This

would suggest that the only market for the new materials would be the R&D

community, which is a real market and one that is extremely interested in buying

new materials; but in very small quantities.

Fortunately, there are also signs that the transparent electronics market isbeginning to move beyond the niche products that are mentioned above. It is

particularly gratifying that transparent displays are now moving from being the

province of little signage firms to one that interests the likes of Apple, LG,

Microsoft and Samsung. And when one digs down a little further it is possible to

find interest in designing transparent solar panels from major PV firms.


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Chapter-7

FUTURE SCOPEIt should be apparent from the discussion that although much progress has

been made in developing new materials and devices for high performance

transparent solar cells, there is still plenty of opportunity to study and improve

device performance and fabrication techniques compared with the nontransparent

solar cell devices. In particular, the stability of transparency solar cells has not

been studied yet. Solution-processable transparent PSCs have become a promising

emerging technology for tandem solar cell application to increase energy

conversion efficiency. The transparency of solar cells at a specific light band will

also lead to new applications such as solar windows. The field of energy harvesting

is gaining momentum by the increases in gasoline price and environment pollution

caused by traditional techniques. Continued breakthroughs in materials and device

performance, accelerate and establish industrial applications. It is likely that new

scientific discoveries and technological advances will continue to cross fertilize

each other for the foreseeable future.

Fig 7.1 Graphene is transparent and can be used as material

It would not be a complete surprise to find players in the smart window;

sensor and lighting industries also begin to invest substantially in transparent

electronics over the next few years.


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Chapter-8

CONCLUSION

Oxides represent a relatively new class of semiconductor materials appliedto active devices, such as TFTs. The combination of high field effect mobility and

low processing temperature for oxide semiconductors makes them attractive for

high performance electronics on flexible plastic substrates. The marriage of two

rapidly evolving areas of research, OLEDs and transparent electronics, enables the

realization of novel transparent OLED displays. This appealing class of see

through devices will have great impact on the humanmachine interaction in the

near future. EC device technology for the built environment may emerge as one of

the keys to combating the effects of global warming, and this novel technologymay also serve as an example of the business opportunities arising from the

challenges caused by climate changes The transparency of solar cells at a specific

light band will also lead to new applications such as solar windows. The field of

energy harvesting is gaining momentum by the increases in gasoline price and

environment pollution caused by traditional techniques. Let us hope that we are

soon going to see transparent technology being implemented in our lives.

Fig 8.1 Usage of Transparent Electronics devices in future


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Chapter-9

REFERENCES Transparent Electronics , Springer publications,

J.F.Wager, D. A. Keszler, R. E. Presley.

Transparent electronics: from synthesis to applications,Wiley publications: Antonio Facchetti, Tobin J. Marks.

www.wikipedia.org www.ieee.org www.alternative-energy-news.info/transparent-a-solar-energy-breakthrough/ www.nanomarkets.net www.nikkeibp.co.jp

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