Second APOSTILLE workshop 9. – 11. May 2013, Novi Sad, Serbia

PRINTED SENSORS – STATE OF THE ART AND THE LATEST TRENDS Danijela Randjelović1, Tadeja Muck2, Grigoris Kaltsas3

1IHTM

– Institute of Microelectronic Technologies and Single Crystals, University of Belgrade, Belgrade, Serbia

2University

of Ljubljana, Faculty of Natural Sciences and Engineering, Ljubljana, Slovenia

3Technological

Educational Institute (T.E.I) of Athens, Department of Electronics, Athens, Greece

[email protected]

Outline Advantages of printed vs. Si-based sensors New applications emerging from the printed functionality Printing technologies and their potential in sensor fabrication Substrates suitable for printed sensors State-of-the-art in printed sensors

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Printing vs. Silicon Technology Low CapEx (capital expense requirements) (100x less)

Expensive dollars)

Commercial cheap printing equipment

Highly skilled personnel

and

compact

Extremely fast production Simple fabrication steps Additive process (materials put only where wanted, little waste) Flexible production (prototyping to large-scale) Various substrates Low temperature processing

Controlled rooms

facilities

(billions

environment,

of

clean

Time consuming, complex, multiple steps processing Photolithography, implantation, diffusion, wet and plasma etching, sputtering ... Non-eco-friendly materials, gases and chemicals used

Large area high yield

High T, high p processing, Energy consuming

Eco-friendly

Hazardous waste non-eco-friendly

Unmatched cost-per-function

High cost (packaging,...)

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Printed vs. Silicon-Based Sensors PRINTED SENSORS: thin, flexible, robust

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

SILICON SENSORS: thick, rigid, brittle

Printed Sensors - challenges Development of new materials (inks) which will act as: conductors, semiconductors, dielectrics, functional materials Customized inks are sometimes needed for printed sensors Tailoring of electrical, optical, mechanical properties of inks by adjusting the chemical composition of ink Inks with „beyond color“ functionality Resolution much lower than photolithography Optimized printing systems Choosing the right substrate (matching the ink and substrate properties, adhesion, wetting, ...) Multidisciplinary knowledge (chemistry, physics, materials science, electronics engineering, MEMS, NEMS) Commercial products 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

New Applications Emerging From the Printed Funcionality There are many needs in industrial, consumer, medical, security etc. markets which can be addressed only by novel types of sensors Printing is enabling development of these new devices Unlike too expensive and rigid Si sensors, printed sensors open new areas of application Printed sensors are inexpensive and flexible, suitable for „one-time use“ Realization of „Truly mobile lab-on-a-chip“ (real-time test of medical, environmental, chemical, biological samples) Real-time indicators of food quality (smart food packaging) Biometrics-based personal identification (travelling abroad, accessing bank accounts, entering protected areas, ...)

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Printing technologies and their potential in sensor fabrication Commercial printers can be used Unlike in ordinary printing, sensors need inks with special properties (electrical, thermal, optical, mechanical) Liquid functional materials are developed Any printing technique flexographic, ...)

can

be

used

(offset,

inkjet,

screen,

Depending on materials used and specific application optimal printing technique should be chosen Combination of several printing techniques

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Inkjet printing ADVANTAGES Already widely electronics

LIMITATIONS used

in

printed

Digital non-contact technique Simple, flexible, can be adapted to mass production Low cost (low material consumption) Suitable for thin layers Good control of film quality/thickness High speed, resolution, accuracy Fast prototyping Suitable for various (all) substrates (rough-smooth, rigid-flexible, flat-curved (3D),...) Additive process 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Requires specially formulated inks that does not clog the nozzles State of the art inkjet printers resolution - 20 µm >> typical size of MEMS devices and IC circuits

Screen printing ADVANTAGES

LIMITATIONS

Relatively simple Also used in printed electronics Provides inkjet

sharper

edges

than

Suitable for quick deposition of thick layers Suitable for various materials even with high viscosity Various commercial available

inks

are

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

State of the art screen printers resolution - 40 µm >> typical size of MEMS devices and IC circuits Not suitable for thin layers High cost of masks High consumption and waste of ink

Nanoimprint lithography ADVANTAGES Sub-micron resolution (20 nm) 3D stamp is pressed into liquid functional material, UV/heat curing, removal of the stamp Resist holds the 3D pattern

LIMITATIONS Requires 3D stamp, fabricated using standard photolithography Developmnet of liquid functional materials with desired properties (electrical, optical, mechanical) Liquid functional material should also be suitable for UV or thermal curing

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

1st Integrated Printed Electronic System Integration of: - rewritable memory (Thinfilm), - organic logic circuitry (PARC), - temperature sensor (PST Sensors) - electrochromic display (ACREO)

Thin Film Electronics ASA, Oslo, Norway Leader in the development of printed electronics The first to commercialize printed rewritable memory December 2012 - the first prototype of an integrated printed electronic tag based on rewritable memory SOURCE: www.thinfilm.no 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Intelligent Tags

Application: Monitoring of storage temperature (perishable foods, vaccines, pharmaceuticals ...) Detection of surpassing temperature thresholds of perishable goods If temperature exceeds the threshold, the information is stored in memory Commercialization: 2014

SOURCE: www.thinfilm.no 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Substrates suitable for printed sensors

Paper Glass Plastics (PET – polyethylene terephtalate, PI – polyimide) Rubber-like polymers (PDMS – poly(dimethysiloxane)) Some more unconventional substrates ...

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Substrates suitable for printed sensors -Skin

Commercialization: MC10 Inc. Cambridge, MA, USA 2008 – STRETCHABLE CIRCUITS Prof. John Rogers (University of Illinois, Urbana-Champaign) Moto: „Making electronics to conform to us“ Reshaping electronics: bend, stretch, flex maintaining performance SOURCE: www.mc10inc.com 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

„Electronic tattoo“ by MC10 „EPIDERMAL ELECTRONICS“ Devices consisting of ultrathin electronics, sensors, electrodes, wireless power and communication systems Before: Devices applied to elastomer backing (easily detached by water) NEW SOLUTION: Printing device on the skin Technology: Rubber stamp prints the ultrathin mesh electronics directly to skin Protection: Commercial „spray-on-bandage“ thin protective and bonding layer (durability: 2 weeks) Applications – health, sport, welness monitoring: temperature, hydratation, blood pressure, insulin level, sun exposure, strain, wound healing SOURCE: www.technologyreview.com 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Substrates suitable for printed sensors - Silk

Biocompatible, eco-friendly, mechanically robust, flexible Besides films, can have variety of forms (gel, sponge, foam) Bio- and eco-resorbable (in humans and environment) Chemical-free techniques for fabrication of silk sensors Inkjet printing is suitable for direct print of functional components on silk SOURCES: google photos, www.nytimes.com 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Edible food quality silk sensors Gold on silk sensor „patches“ tested on apples, eggs, cheese, banana, milk Both Au and silk are edible and biodegradable Low-cost RFID tag, antenna-based passive device Principle of operation: Resonant frequency of Au antenna changes due to changes in food quality (contamination, ripening, ...) Banana ripening over 9 days:

∆f = 6.5 MHz (effective permittivity

drops)

Silk acts like glue when exposed to water vapor – easy sticking

Tufts University – EDIBLE silk sensors for monitoring food quality. SOURCE: www.bsclarified.wordpress.com, www.fastcoexist.com 2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Conclusion

Interest in printed sensors is driven by fast development of the printed electronics industry The main benefit of printed sensors is that their fabrication is based on cost-effective additive printing processes that doesn’t require expensive and complex infrastructure like the one existing in semiconductor industry Printing is capable of replacing standard Si-based technology Printed sensors open new areas of application in industrial, consumer, medical, security etc. markets

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.

Acknowledgement

This

work

was

promoted

by

European

Concerted Research Action - COST Action FP1104: NEW POSSIBILITIES FOR PRINT MEDIA AND PACKAGING – COMBINING PRINT WITH DIGITAL

2nd APOSTILLE workshop, Novi Sad, Serbia, 10.5.2013.