-
- News
- Books
Featured Books
- design007 Magazine
Latest Issues
Current IssueLearning to Speak ‘Fab’
Our expert contributors clear up many of the miscommunication problems between PCB designers and their fab and assembly stakeholders. As you will see, a little extra planning early in the design cycle can go a long way toward maintaining open lines of communication with the fab and assembly folks.
Training New Designers
Where will we find the next generation of PCB designers and design engineers? Once we locate them, how will we train and educate them? What will PCB designers of the future need to master to deal with tomorrow’s technology?
The Designer of the Future
Our expert contributors peer into their crystal balls and offer their thoughts on the designers and design engineers of tomorrow, and what their jobs will look like.
- Articles
- Columns
Search Console
- Links
- Media kit
||| MENU - design007 Magazine
Decoupled Graphene Thanks to Potassium Bromide
April 29, 2019 | University of BaselEstimated reading time: 2 minutes

The use of potassium bromide in the production of graphene on a copper surface can lead to better results. When potassium bromide molecules arrange themselves between graphene and copper, it results in electronic decoupling. This alters the electrical properties of the graphene produced, bringing them closer to pure graphene, as reported by physicists from the universities of Basel, Modena and Munich in the journal ACS Nano.
Image Caption: Potassium bromide molecules (pink) arrange themselves between the copper substrate (yellow) and the graphene layer (gray). This brings about electrical decoupling, as demonstrated by scanning probe microscopy studies.
Graphene consists of a layer of carbon atoms just one atom in thickness in a honeycomb pattern and is the subject of intensive worldwide research. Thanks to its high level of flexibility, combined with excellent stability and electrical conductivity, graphene has numerous promising applications—particularly in electronic components.
Molecules for Decoupling
Graphene is often produced via a chemical reaction on metallic surfaces in a process known as chemical vapor deposition. The graphene layer and the underlying metal are then electrically coupled, which diminishes some of the special electrical properties of graphene. For use in electronics, the graphene has to be transferred onto insulating substrates in a multistep process, during which there is a risk of damage and contamination.
In order to obtain defect-free, pure graphene, it is therefore preferable to decouple the graphene electrically from the metallic substrate and to develop a method that allows easier transfer without damage. The group led by Professor Ernst Meyer from the Department of Physics and the Swiss Nanoscience Institute (SNI) of the University of Basel is investigating ways of incorporating molecules between the graphene layer and the substrate after the chemical deposition process, which leads to this type of decoupling.
Altering Electrical Properties
In a study carried out by SNI doctoral student Mathias Schulzendorf, scientists have shown that potassium bromide is ideally suited to this. Potassium bromide is a soluble hydrogen bromide salt. Unlike the chemically similar compound sodium chloride, potassium bromide molecules arrange themselves between the graphene layer and the copper substrate. This was demonstrated by researchers in a variety of scanning probe microscopy studies.
Calculations performed by colleagues at the University of Modena and Reggio Emilia (Italy) explain this phenomenon: It is more energetically advantageous for the system if potassium bromide molecules arrange themselves between the graphene and copper than if they are deposited on the graphene—as happens with sodium chloride.
The researchers have shown that the intermediate layer of potassium bromide alters the electrical properties of graphene—until they correspond to those expected for free graphene. “Our work has demonstrated that the graphene and the underlying metal can be decoupled using potassium bromide, bringing us a key step closer to producing clean and defect-free graphene,” says project supervisor Dr. Thilo Glatzel, who is a member of Meyer’s team.
Suggested Items
Real Time with... IPC APEX EXPO 2025: Tariffs and Supply Chains in U.S. Electronics Manufacturing
04/01/2025 | Real Time with...IPC APEX EXPOChris Mitchell, VP of Global Government Relations for IPC, discusses IPC's concerns about tariffs on copper and their impact on U.S. electronics manufacturing. He emphasizes the complexity of supply chains and the need for policymakers to understand their effects.
The Chemical Connection: Surface Finishes for PCBs
03/31/2025 | Don Ball -- Column: The Chemical ConnectionWriting about surface finishes brings a feeling of nostalgia. You see, one of my first jobs in the industry was providing technical support for surface cleaning processes and finishes to enhance dry film adhesion to copper surfaces. I’d like to take this opportunity to revisit the basics, indulge in my nostalgia, and perhaps provide some insight into why we do things the way we do them in the here and now.
NUS Physicists Discover a Copper-free High-temperature Superconducting Oxide
03/28/2025 | PRNewswireProfessor Ariando and Dr Stephen Lin Er Chow from the National University of Singapore (NUS) Department of Physics have designed and synthesised a groundbreaking new material—a copper-free superconducting oxide—capable of superconducting at approximately 40 Kelvin (K), or about minus 233 degrees Celsius (deg C), under ambient pressure.
AT&S Sets New Standards in the Recycling of Copper and Chemicals
03/25/2025 | AT&SAT&S has been working for years to reduce the ecological footprint of its production sites worldwide with a comprehensive sustainability strategy and considerable investments.
Empowering the Future of Advanced Computing and Connectivity: DuPont Unveils Innovative Advanced Circuit Materials in Shanghai
03/24/2025 | DuPontDuPont will showcase how we are shaping the next generation of electronics at the International Electronic Circuits (Shanghai) Exhibition 2025.