Printed Cirsuits
A study on the use of electronic components that are fixed to a sheet of paper can be the answer to the massive problem of waste from electronics, like computers and cell phones. The circuit board, which is made of paper, has fully integrated electrical components and when no longer needed can be burned or left to degrade.
burning circuits
The study, done by a team of researchers out of the State University of New York at Binghamton at the Bioelectronics and Microsystem Laboratory in the Department of Electrical and Computer Engineering, has found a way to print circuits on a sheet of simple paper, and able to dispose of it simply, safely, and sustainably.
Printed Circuit Boards that we find in our electronics are made of glass fibers, resin, and metal. They tend to be bulky and very hard to dispose of in any meaningful way. The poor disposability is especially troubling at this time, because of the newest single-use devices and sensors, that are mainly used in medicine when evaluating health and monitoring environmental conditions, as well as other novel conditions.
The researchers ran into a problem that many would think of immediately. You can’t use traditional components on a paper circuit board, even if it is a sound base for them. Instead, the team wanted to develop circuitry components that would be simple to manufacture and that had all the electronic components completely integrated into the sheet, already.
The team developed a special paper-based amplifier-type circuit that incorporates resistors, capacitors, and a transistor. They used wax to print the channels onto a sheet of paper, in a simple pattern. After melting the wax so it soaked into the paper, semi conductive and conductive inks were printed in areas not soaked by wax.
On the final two layers, screen-printed additional conductive metal components were added, and then the team cast a gel-based electrolyte onto a paper sheet.
The tests revealed that the resistor, capacitor, and transistor designs performed properly. The final circuit was thin and very flexible just like paper, even with the addition of components. To prove degradability the team used a flame to set the circuit on fire, and it quickly burned to ash. The team felt this was then a good start to producing completely disposable electronic devices.
Humanity’s excessive production of material waste poses a critical environmental threat, and the problem is only escalating, especially in the past few decades with the rapid development of powerful electronic tools and persistent consumer desire to upgrade to the newest available technology. The poor disposability of electronics is especially an issue for the newly arising field of single-use devices and sensors, which are often used to evaluate human health and monitor environmental conditions, and for other novel applications. Though impressive in terms of function and convenience, usage of conventional electronic components in these applications would inflict an immense surge in waste and result in higher costs. This work’s primary objective is to develop a cost-effective, eco-friendly, all-paper, device for single-use applications that can be easily and safely disposed of through incineration or biodegradation. All electronic components are paper-based and integrated on paper-based printed circuit boards (PCBs), innovatively providing a realistic and practical solution for green electronic platforms. In particular, a methodology is discussed for simultaneously achieving very tunable resistors (20 Ω to 285 kΩ), supercapacitors (∼3.29 mF), and electrolyte-gated field-effect transistors on and within the thickness of a single sheet of paper. Each electronic component is completely integrated into functionalized paper regions and exhibits favorable electrical activity, adjustability, flexibility, and disposability. A simple amplifier circuit is successfully demonstrated within a small area and within the thickness of a single sheet of paper, displaying component versatility and the capability for their fabrication processes to be performed in parallel for efficient and rapid development.
