Research - Organic Circuits
Imagine taking out a thin transparent slice of plastic the size of a credit card which can unfold and become your laptop! This is the promise that futuristic organic circuits hold, if their full capacity is taken advantage of this scenario may no longer be just science fiction.
Have you ever wondered what makes our phones and computers work? What’s hidden in those tiny chips that that power our digital lifestyle? At the heart of these chips is a single component called a “transistor”, it’s the building block to every electronic component we have today. You can think of it as a tiny switch which is constantly turning on and off. How tiny? Well current transistors can be made as small as 10nm, that’s 10,000 times smaller than the width of your hair! Since its discovery in 1947 [2] the transistor has been made of rigid inorganic materials such as Silicon, however there’s another family of materials based on carbon called organics. Organic materials are heavily studied in the life sciences since they are the basis for living compounds, like us! Recently researchers have asked themselves if organic materials can also be used make transistors as well. If transistors could indeed be made of organic materials the circuits used in our electronics would offer something that conventional inorganic materials can’t, this is, flexibility, transparency and recyclability. Organic based circuits are also cheaper and can have longer battery lives’ which in turn save you money. For all of these reasons researchers believe that organic electronics are a promising technology for the future of our devices.
Organic circuits have been studied for quite a while (>60yrs.), however they remained in the lab due to the difficulties of producing them in large quantities as well their instability when exposed to air. Much like the food you eat (which is Carbon based i.e. Organic) organic electronics can also decay over time. Moreover, organic circuits have had difficulties entering the mainstream market due to their poor performance as compared with conventional silicon electronics. They suffered from being slow, unstable and difficult to work with. Many of these problems were addressed in the late 80’s when researchers from Eastman Kodak Co. demonstrated the first organic light emitting diode (OLED) that was stable and efficient. An OLED is similar to a light bulb only it’s much tinier (100-500nm which is 200 times smaller than the thickness of your hair) and can shine brighter and last longer. Although the goal of making a transistor using organics hadn’t been met, making a tiny light bulb was still a huge deal and it attracted the attention of the industry for the first time. Organic circuits were now seen as a serious commercial platform for future electronics.
Since Kodak’s demonstration of an OLED companies like Samsung have started offering the first OLED based TV’s that are now competing with LCD displays. The reason that they found easy entry into the field of displays and lighting is that making a light emitting device (i.e. a tiny light bulb) is quite a bit simpler than making a transistor. A transistor is more complicated and requires more sophisticated design. Nevertheless Samsung has been the leader in developing OLED TV’s showing impressive advances such as a flexible [6] and transparent [7] displays. This is a stepping stone towards our foldable laptops! Another area of interest for organics is in lighting where industry giants such as LG are paving the way towards new OLED based bulbs. Their attraction is that they are easily recycled and decomposed making them environmentally friendly. OLED light sources are also “human friendly” since they do no emit UV rays which can cause sleep disorders. Currently OLED lighting suffers from high costs due to their costly manufacturing, shorter lifetimes as compared to LED bulbs, as well as smaller levels of brightness. It may take up to twice as many OLED bulbs to achieve the same levels of illumination as a traditional LED [9]. OLEDs are also sensitive to heat and can easily deteriorate making them unsuitable for high temperature areas (such as above your stove). While there are definitely many advantages that OLEDs have over traditional LEDs there are still quite a few road blocks to overcome before they hit the everyday consumer market.
Until now we’ve seen how organic electronics have been integrated mainly into the lighting field, but there’s another huge field that organics could also disrupt, this is the electronics arena. As we discussed earlier, organics found easy entry into the field of displays and lighting because making a light emitting device is quite a bit simpler than making a transistor. Nevertheless, the question of what can organic electronics really do (if they were one day created) begs an answer. Predicting the future of any technology is quite difficult (just ask… well basically any scientist who’s tried to do it!) but if we can imagine a blue sky scenario where everything that can be accomplished with this technology comes true then we can have some real fun imaging what the future beholds. With current trends in printing live tissue, it’s not too farfetched that we would one day also be able to purchase a printer that prints out a smartphone or any other electronic device we want. But why stop there? Due to their flexibility and bio-compatibility it’s conceivable that we could one day embed devices into our own organs! Image a set of lungs that tell you the quality of the air your breathing, or fingertips that measure your measure blood pressure and warn you when you might have a heart attack. Not enough? How about eyes that can see in the dark (UV-Organics) or readjusting our eardrums so that we can hear different frequencies (like a dog whistle). It may all be possible with organics!
Organic circuits have come a long way since Kodak demonstrated their promise in the late 80s, most of the applications have been in display and lighting with the former being already integrated into the consumer market. Their transparency, flexibility, low power consumption and environmentally friendly nature make organic circuits very promising for future electronics. Organics have significantly advanced in the lighting arena but still have quite a bit of challenges in the digital electronics area, this is because making an OLED is much simpler than making an organic transistor. But if scientists could crack the puzzle of making such a circuit, then it could truly revolutionize our technology and life styles, can’t wait to get those new pair of night vision eyes!
Author: Brian Calderon
References
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