-
- News
- Books
Featured Books
- smt007 Magazine
Latest Issues
Current IssueThe Rise of Data
Analytics is a given in this industry, but the threshold is changing. If you think you're too small to invest in analytics, you may need to reconsider. So how do you do analytics better? What are the new tools, and how do you get started?
Counterfeit Concerns
The distribution of counterfeit parts has become much more sophisticated in the past decade, and there's no reason to believe that trend is going to be stopping any time soon. What might crop up in the near future?
Solder Printing
In this issue, we turn a discerning eye to solder paste printing. As apertures shrink, and the requirement for multiple thicknesses of paste on the same board becomes more commonplace, consistently and accurately applying paste becomes ever more challenging.
- Articles
- Columns
Search Console
- Links
- Media kit
||| MENU - smt007 Magazine
A New Skoltech Patent: Defect-free Graphene for Flexible Transparent Electronics
November 22, 2022 | SkoltechEstimated reading time: 3 minutes
Skoltech researchers have patented a method that enables producing arbitrarily shaped functional graphene components on a transparent substrate with 100-nanometer resolution, which hold much promise for flexible and transparent electronics. The new approach helps avoid defects that arise during graphene transfer between substrates and strongly affect the material’s quality.
“Flexible and transparent electronics is typically associated with wearable biosensors that monitor vital signs, such as heart rate, breathing, and blood oxygenation, and relay them to a smartphone or fitness band,” Skoltech PhD student Aleksei Shiverskii, one of the inventors, comments. “An affordable and efficient technology that at first may seem impractical soon becomes a ubiquitous and indispensable appliance, like a bluetooth electric kettle or a wifi vacuum cleaner. I believe that someday flexible and transparent electronics will become a fixture, too.”
Currently, metallic meshes embedded in polymer or glass are used as conductors in flexible transparent electronics. The most common metals for a mesh are copper, silver, and even gold or platinum for hi-end devices. However, the metallic meshes that heat the glass can hardly be called transparent. Although they cope quite well with their task, the finest mesh only lets through about two-thirds of the light. As opposed to metallic meshes that you can see with a naked eye, graphene is more transparent, less visible, and highly conductive. Besides, some studies show that graphene has higher bending fatigue strength and, therefore, can last longer.
Importantly, graphene is made from much cheaper and eco-friendlier materials as compared to pure metals and, unlike copper or silver, is not susceptible to oxidation.
Typically, graphene is synthesized on a temporary substrate and then transferred onto a permanent polymer substrate that supports and shapes it as needed. The transfer is performed using the poorly scalable Langmuir-Blodgett method that tends to cause defects and impair the quality of graphene. The Skoltech team has come up with an alternative solution to deal with the transfer issue that prevents widespread adoption of graphene in flexible transparent electronics.
“Graphene is usually produced using a temporary flat substrate. In the Langmuir-Blodgett method, the substrate is dissolved once the synthesis is complete, with graphene film left floating on the liquid surface. Then a permanent substrate is slipped under the film for graphene to take the required shape. It is at this point that defects appear in the material,” Shiverskii explains.
“In our method, the temporary substrate is made to match the ultimately desired graphene shape. Once we have placed the permanent substrate onto the film, we remove the temporary one. Since graphene settles down in its final shape, there is no need to drape it over the permanent substrate, which helps avoid wrinkles and other defects. The 3D temporary substrate offers much broader possibilities than conventional techniques. Now, along with 2D or quasi-2D circuits we can produce 3D circuits of whatever complexity we wish with a resolution of several dozen nanometers,” patent co-holder and Skoltech Assistant Professor Sergey Abaimov says.
He continues, “The patent discloses a specific optimal lab-tested method, in which we create a photopolymer mask with the shape of the future graphene structure on a catalytic copper substrate, coat it with chromium, and then remove the polymer, leaving a negative chromium mask of the required shape on the substrate. We use chromium because it withstands high-temperature synthesis and passivates graphene in covered areas. Along with this method, the patent presented more general approaches — both in the description and formula — covering a broad range of alternative methods.”
“I expected multiple revisions of this complex patent but to my surprise, the application was approved right away, with only minor technical corrections. I hope that our research will have wide application and help propel Russian technology in flexible and transparent electronics to new heights,” Abaimov concludes.
Suggested Items
American Made Advocacy: There's No Substitute for American-made Microelectronics
11/04/2024 | Shane Whiteside -- Column: American Made AdvocacyThe COVID pandemic put a spotlight on the fragility of the global supply chain. Disruption has become the new normal. Companies now see that one political decision or other interruption in Asia could bring the electronics industry to its knees. With 90% of the world’s PCBs and almost all IC substrates made in Asia, the current state of the electronics supply chain continues to present significant risk to the U.S. market.
Altus Sees Growing Interest for Laser Depanelling Solutions
11/04/2024 | Altus GroupAltus Group, a leading distributor of capital equipment in the UK and Ireland, has seen an increasing interest in laser depaneling systems from LPKF in 2024.
IMI Reports $841 Million Revenues in First Nine Months of 2024
11/04/2024 | IMIIntegrated Micro-Electronics, Inc. (IMI), a global leader in electronics manufacturing services, announced its financial results for the first nine months of 2024.
DuPont Earns Best Partner Award for Innovation from Samsung Electronics
10/31/2024 | DuPontDuPont announced it has been selected for the 2024 Best Partner Award from Samsung Electronics in the Innovation category.
Are Firms Holding Too Much Inventory?
10/30/2024 | Shawn DuBravac, IPCIn the aftermath of the 2008 financial crisis, manufacturers made significant adjustments to inventory management strategies as they faced sharp declines in demand and economic uncertainty. Manufacturers moved to scale back production and attempted to quickly reduce inventory levels. Post-crisis, many manufacturers adopted lean inventory practices, such as just-in-time (JIT) production, to minimize holding costs and illiquidity risks.