PCB News - Graphene circuit board drawing may become a reality

This article is mainly about the introduction of fast drawing or becoming a reality for graphene circuit boards

Researchers at the University of Illinois, Urbana-Champaign reportedly found a single-step room temperature process that can quickly map graphene circuit boards with a simple shadow mask and transfer them To the flexible substrate.

Through chemical vapor deposition (CVD), it is easy to grow graphene on copper foil, but engineers have been struggling to find a simple way to etch the required circuit pattern and transfer it to a non-metal substrate. Now, researchers at the University of Illinois (Urbana-Champaign) have reportedly found a single-step room temperature process that can quickly map graphene circuits with a simple shadow mask and map them. Transfer to a flexible substrate.

For many years, engineers have known that graphene is very easy to deposit and form on copper foil by CVD. However, the researchers pointed out that they still have to spend a lot of time growing graphene on silicon substrates before they can use traditional techniques to map circuit boards.

This room temperature method replaces the method of growing graphene on copper foil, and uses its claimed one-step process to etch and transfer graphene circuits to almost all kinds of substrates, even including future flexible polymerization Substrate. The trick is to cut out the circuit pattern to a simpler light shield.

“Researchers first use computer-aided design (CAD) software to design the required micro-patterns, connect a commercial laser cutting machine to a computer, and make a corresponding hood,” said Keong Yong, a PhD candidate at the University of Illinois at Urbana-Champaign. “These The rapid design iteration cycle and pattern reproduction are manufactured by a fast-running laser cutter, and low-cost polymer and metal sheets are drawn.” Keong Yong is currently working on the research team led by the school’s professor SungWoo Nam. Research.

Once the cutting is complete, the light shield is placed on the copper foil deposited with CVD graphene, and then etched with oxygen plasma. Then, the patterned graphene is transplanted onto the flexible PCB substrate by a lamination process to ensure conformal contact so that the copper foil can be etched away.

"Because this approach is easy to implement, our method does not require complex traditional micro-manufacturing processes and polymer scaffolds, which greatly reduces the overall manufacturing steps and time." Yong said: "More importantly, we use polymer-free The pathway also brings cleaner graphene."

At present, when graphene wafers are manufactured by this method, there is no size limit, but it is still limited by the etching precision of the light shield. In order to achieve complete silicon processing, this mask manufacturing process still has a long way to go. It is limited to today's micron-level PCB circuits, not the nano-level range.

The above is mainly an introduction to quickly drawing or becoming a reality for graphene circuit boards