Engineers at the University of Cambridge recently developed a form of transistor that could function for months, or even years, without a battery by feeding energy from its environment. This form of scavenging for energy is akin to the principle of a computer on sleep mode.
A typical characteristic among transistors is that a tiny leakage of electrical current seep out from it. This leakage, known as a near-off-state current, is being harnessed by the transistor to fuel its operation.
'Non-Desirable' Characteristic Avoided By Engineers
This marks the first time that this small dissipated energy has been effectively captured and used to function a certain device, said Science Daily. The innovation opens up doorways on how to design the Internet of Things, a proposed advancement of the Internet in which everyday objects has network connectivity, allowing them to send and receive data.
The design for the new transistor is based on a unique geometry which uses a "non-desirable" characteristics, which is basically the point of contact between the metal and semiconducting parts of a transistor known as the Schottky barrier. The transistor can be created at low temperatures and is applicable in any material, from glass and plastic to polyester and paper.
"We're challenging conventional perception of how a transistor should be," said Professor Arokia Nathan of Cambridge's Department of Engineering, the paper's co-author. "We've found that these Schottky barriers, which most engineers try to avoid, actually have the ideal characteristics for the type of ultra low power applications we're looking at, such as wearable or implantable electronics for health monitoring."
New Transistor Makes Totally Autonomous Electronics A Possibility
This design solves one of the main concerns of creating transistors at very small sizes. The previous problem mainly revolves around how a miniature transistor's electrodes start influencing one another because of how proximal they are, explained Cam.
Through this new design, however, the Cambridge researchers were able to take advantage of the Schottky barriers and kept the electrodes independent from one another. The design also gives the transistor a high level of gain, or put simply, it amplifies the transistor's signal. The transistor's operating power is less than a volt, with the device consuming only below a billionth of a watt to function.
"This is an ingenious transistor concept," said Professor Gehan Amaratunga, Head of the Electronics, Power, and Energy Conversion Group at Cambridge's Engineering Department. "This type of ultra-low power operation is a prerequisite for many of the new ubiquitous electronics applications, where what matters is the function -- in essence 'intelligence' -- without the demand for speed."
The professor went on to add that the transistor takes us a step closer in creating a totally autonomous electronics. Amaratunga compared the transistor's energy-harvesting method around its environment similar as to how bacteria in biology thrives.