A photo-frame on the bed-side table beeps to wake you up. The curtains slowly turn translucent, permitting the sunlight to seep in. The synthetic patch on your arm by now shares your body temperature and blood pressure to the screen that, so far, had been an alarm-clock. A voice command enables your curtains to turn opaque once more to display vital information you need to start the day ahead. The day has just begun and many more such applications await your attention. Welcome to the futuristic world of flexible electronics.
Thin-films on window panes or on the rooftop, sensors that help to monitor personal health, checking the circulation of fake products and smart wearables are some of the possible applications. Imagine a world where every individual product has its unique digital identity. The letters you send, the answer scripts you wrote, the book, you misplaced, with its own imprinted identity will be trackable too.
For half a century, researchers have managed to build integrated circuits on thin rigid single crystal wafers of material, such as silicon. They indeed have touched almost all aspects of our modern lives, turning activities that were figments of wildest imagination into realities. One just needs to look at the smartphones that many of us carry. However, there has always been a desire to make the electronics on foldable, or flexible substrates. Making electronics directly on flexible substrates is the domain of the emerging technology of flexible electronics.
Foldable flat surfaces, referred to as substrates, like paper, cloth, metal foil or plastic, can be used to make flexible electronics which can be used in virtually all locations – be it modern factories, workplaces or inside homes. The opportunities for applying this technology are endless. Circuits can be printed on large surfaces and can be manufactured like newspapers by the printed process. If such printing is on large scale it is possible to make electronics with these applications affordable at really low costs. The products can also be eco-friendly and biodegradable which is bound to become a requirement for all products in the not too distant future.
In terms of industrial use, foldable electronics will be of immense use. Product packaging, inventory, logistics – from the manufacture to the disposal stage, every product will be accounted for.
The global market
Flexible electronics is an emerging technology. Estimates suggest the global market is worth around $40 billion. However, experts suggest that much of such number-crunching depends on what’s being considered flexible electronics. Much of the growth in years ahead depends on the adaptability of the technology.
Globally, the USA, European countries – Germany, Finland, Denmark, Taiwan, South Korea and Japan are the nations, where much of the development is taking place. When it comes to applications, consumer electronics lead the way – OLED-based display is a leading example. Several alliances are also in place, worldwide, to congregate stakeholders and find new solutions.
The Indian scenario
A variety of academics across the country work on various aspects of flexible electronics – materials, devices and systems. Almost all advanced institutes/universities have scientists and academicians working in these areas. Two of the key components of flexible electronics manufacturing – inks and printing – have good prospects in India. There are many successful industries in printing technology as well as chemical synthesis as in pharmaceuticals – and indeed India has a respectable standing in the world.
To encourage domestic development of large-area flexible electronics, Government of India’s Ministry of Electronics and Information Technology (MeitY) and Indian Institute of Technology (IIT), Kanpur, facilitated setting up of National Centre for Flexible Electronics (FlexE Centre also known as NCFlexE) in 2014. The centre facilitates the integration of electronics on flexible material such as plastic sheets, paper, metal foils, and in some cases cloth, and in turn, helps in the development of applications.
Interest in flexible electronics is also evident in the private sector, and many are coming on board over time. The centre is in touch with many organisations – industries and academic institutions – and is having around 100 non-disclosure agreements to carry out discussions on potential technological cooperation. Over 20 industrial partners have worked closely with the centre on flexible electronics applications. This has resulted in prototypes and products in the area of inks, smart packaging, flexible printer heaters, wearable devices, lighting and various health care products.
Some of the applications developed at FlexE Centre at IIT Kanpur
First passive matrix display from India
FlexE Centre’s mother centre, Samtel Centre for Display Technologies (SCDT), a multi-disciplinary research centre at IIT Kanpur, fabricated India’s first passive matrix OLED display (An OLED technology used for displaying images).
‘Checko’, an anti-counterfeiting product developed for identification of fake products. The product has drawn the attention of industries to protect their brands, where it is already being put to use. It also finds application in excise tax stamps and document security.
Contact-based unique electronic signature label
This application provides electronic identity on a label. The labels can be used in place of holograms.
Flexible Electronic Axillary (Armpit) Thermometer
A thermometer that separates sensor picking temperature, and the reading mechanism and screen. The patient who wears his/her personalized sensor need not be woken up by the nurse when he/she comes in to measure the patient’s temperature.
Smart electronic label for intravenous fluid level monitoring, an infrared thermometer that grabs reading from a distance and logs the data in a cloud through smart-phone and heater jackets. There are also innovations for the visually impaired – extended reality-based devices for enabling interaction with computers and touch-sensitive digital tactile watches that use vibrations to output time. There are many other applications, in different stages of development.
Unlike challenges of the many developed countries, issues in India are different in context. The FlexE Centre explores solutions which are related to the region and practically applicable. A core-team of 15 steers around 100 professionals working on different projects, at different levels.
In order to get a better understanding of flexible electronics, The Electronics had a chat with Professor S Sundar Kumar Iyer, co-ordinator, National Centre for Flexible Electronics.
Q. What are flexible electronics?
Flexible electronics refers to directly making electronics on any substrate, especially flexible substrates (surfaces). When using flexible substrates, it is possible to often ‘print’ the electronics using roll to roll printers on reams of the substrate. Examples of substrates can be material such as plastic sheets, paper, steel and other metal foils and sheets, in theory, any material on which you will want to implement electronics. In some sense, the most challenging substrate to make electronics will be textiles – which might also be the most versatile and useful for applications.
There are quite a few advantages of using flexible electronics. One is that large areas of electronics can be fabricated with high throughput, i.e., it can be done really fast – like printing newspapers, which in state of the art situations can be several meters printed per minute. So, you can fabricate a lot of electronics really fast. On the other hand, traditional electronics made on single crystal wafers are limited by the size of the wafers. Remarkable though that technology is, the largest silicon substrate one hears about today is 450 mm (about 1.5 feet) in diameter, and the wafers are handled one at a time. So the throughput in traditional electronics is orders of magnitude much slower.
It should, however, be noted that traditional electronics is much more sophisticated and is capable of doing more complex things. Flexible electronics in comparison is in its nascent stage; however, it can implement electronics in applications in which traditional electronics might not have the same advantage.
Q. Where can such electronics be used?
Typically flexible electronics can be used wherever the area over which the deployment is large, or one needs flexibility or bendability or conformality (taking the shape of the environment) requirements. One example of its use is in large-area displays. Indeed, OLED displays are one of the commercial products already available with this technology. One may implement OLED displays in a variety of substrates.
Another large area of application in the future is in photovoltaic (PV) power generation. Lightweight, easily deployable sheets with PV modules built on them can be used for quick deployment in remote places in a variety of situations as in campings or for military deployment in remote areas. The time is not far when we might buy solar panels on a sheet of paper or cloth which can be hung on the cloth line to generate power during the day. But before that, there are still technological problems to be solved to make the flexible electronic PV viable for practical use.
Flexible electronics also finds applications in a variety of packaging, making it smart – be it to help to track the package as in RFIDs or to sense the freshness of the packed food or just as a smart label in a supermarket that explains to the customer through a printed speaker the details of the product.
A wide variety of (chemical, physical, optical, electrical …) sensors – be it to sense contamination levels in water or air or to find the purity of the milk purchased or monitoring the moisture in the fields of a farm to know when the crops need to be watered… the range of applications appear to be endless. The ability to implant them on flexible substrates makes them convenient to use and lowers their cost.
One area I believe flexible electronics will play an important role will be in health care applications. Besides its use as sensors, they find applications as skin patches and are potentially more benign for electronics that might have to be implanted within the body. They can also play an important role in building medical diagnostic equipment. I would also like to add that flexible electronics has the potential to make the product less toxic to the environment and can be made bio-degradable. Thus, this might be the eventual way to avoid electronic waste.
Q. Do you foresee a revolution in appliances?
Most certainly! The ability to incorporate electronics everywhere, that too at a low cost is bound to play the role of disruptive technology – much the way the availability of smartphones has changed life in almost all societies around the world in the most unbelievable of ways.
The day is not far when we will have window curtains also working as a source of diffused lighting for a room, window panes not only act as displays setting the mood in a room but should also double up as for power generation – generating power from solar and ambient light. Smart sensors could be embedded in our clothing and shoes which should help track the health levels of a person. We might have sensors in our refrigerators that will keep track of the freshness of what is stored inside and may order fresh supplies when the supplies go down.
What is important to note is that this technology, in the initial years, will not be replacing traditional electronics (which I believe will continue its incredible journey for at least a few more decades), but it is likely to bring in the convenience of electronics in a variety of spheres of life – just because today’s technological advances allow us to implement them that way.
In the interim, till flexible electronics establishes itself, it is always possible to mix traditional electronics with flexible electronics, as flexible PCB in one of the simplest examples of hybrid electronics.
Q. How long will it take to make the technology available to the masses?
Some of these technologies are already available today in the market. Flexible displays and lighting related products are already introduced in the market. Hybrid electronics such as the use of printed antennas in RFIDs using conventional electronic chips are also already in use.
In many instances, this is a technology that is looking for applications. In those instances, once the application is identified, it should not take more than six months to a year for technological powerhouses to bring out useful products.
For example, at the National Centre for Flexible Electronics at IIT Kanpur, (as with similar facilities located in many places around the world), the basic manufacturing equipment and a significant amount of know-how is already in place. Once the application is known and funding is available, it should be possible to develop and deploy the products fast.
Some of the more advanced applications might take many years to decades to come up with viable products – and I am sure it will be worth the wait.
Q. Can you suggest a few applications which will be in use in the next few years?
As mentioned above, many areas of human activities will find flexible electronics being used for practical commercial applications. I would think some of the areas where we will have consumer products are in health care, clothing (or as some would call wearables) and smart packaging. I would also think that it will play an important role in revolutionising displays, power generation and sensors. OLED displays will continue to improve. With technological breakthroughs, solar modules on flexible substrates will find wider deployment (it is already available today, but is costly and not common). More and more variety of sensors for different applications will continue to be developed which will spur more product development.
Indeed, imagination is the limit and, as they say, necessity is the mother of invention. That is the reason we have launched the innovation challenge to get to know what are the applications that will help find solutions in practical situations in India.
Q. Tell us about FlexE Innovation Challenge
All technological solutions are contextual – invariably coming into being due to the unique needs of the society or economy that is facing the challenges. Some of these challenges are universal. On the other hand, some solutions/products are very specific to socio-economic conditions.
For example, if we look at food wastage, in the developed world, it is usually the unsold produce from super-markets that is thrown into the garbage. On the other hand, in the less developed parts of the world, most of the food wastage is during harvesting, storage and transportation. The latter is often because we do not have the right technology to track and detect the causes of wastage and prevent it early enough from happening. Another example is spoilage or adulteration in milk. This is not something that worries the scientists in Japan or Sweden. But this is a real problem in countries such as India.
In both the examples given above, we cannot expect scientists in the developed world to go out of the way to solve what is essentially our problems. The best way forward is that we learn to solve our own problems. Through the FlexE Innovation Challenge, we want to get inputs from creative minds – from whichever walk of life – to suggest ways in which an electronic solution can be found to problems faced in daily life.
How could electronics help solve problems faced in India conditions – crowded places such as election rallies, or large religions gatherings or maybe busy railway stations and bus stands? What can help ensure tracking freshness or authenticity of food products? Are there any health issues endemic to a place that needs to be tracked or detected? Essentially, any day to day problem that needs a solution with electronics is a potential product in the world of flexible electronics.
Once the problem to be solved is identified, half the battle is already won. That is what we intend to do through the FlexE Innovation Challenge. Please visit us at:
and participate to help solve a practical problem. We hope there will be many participants, especially young and creative minds – who are the future of our country.