Microelectronics receive liquid boost

During two years of research water was found to act as a mask in a process that begins with the creation of patterns via lithography and ends with long, thin graphene nanoribbons.

Unlike most applications, in this instance water has been an essential part of the process

Rice University chemist James Tour

The discovery, led by Vera Abramova and Alexander Slesarev, suggested that nanoribbons form wherever water gathers at the wedge between the raised pattern and the graphene surface.

The water formation is known as a meniscus. Using the Rice University process, the meniscus protects a ribbon of graphene from being etched away when the pattern is removed.

Rice chemist James Tour said that long nanowires such as those created should be of interest to microelectronics manufacturers as they are reaching the limits of miniaturised circuitry.

“Right now, manufacturers can make small features, or make big features and put them where they want them. But to have both has been difficult,” Tour noted.

Tour stated that unlike most applications, in this instance water has been an essential part of the process.

“In our experiments, water accumulates at the edge of the structure and protects the graphene from the reactive ion etching (RIE).”