Technology

Pixels of smartphone screens “suggested” the laser method of graphene production

Many modern smartphones have brightAMOLED displays. At least two silicon transistors are hidden under each individual pixel, mass production of which is carried out using laser annealing technologies. Interestingly, a similar process can also be used to generate graphene crystals. Graphene is a strong and thin carbon nanomaterial that attracts the attention of scientists from all over the world for its remarkable properties, manifested in the ability to conduct electricity and heat.

While traditional methods requiretemperatures above 1000 ° C, laser technology allows you to achieve the same result at lower temperatures, applicable even to plastic substrates (which melt at temperatures below 300 ° C).

Research Group by Professor Keon Jae Lee(KEON Jae Lee) from the Center for Multidimensional Carbon Materials of the Institute for Basic Science (IBS) and the team of Professor Choi Sung-Yool from the Korea Institute of Advanced Technology (KAIST) jointly found a mechanism for the synthesis of graphene using laser-induced phase separation applied to solid-state material - single-chip silicon carbide (SiC).

Results of this study that werepublished in Nature Communications, they clarify how the laser technology in question can separate a complex compound (SiC) into ultrathin carbon and silicon elements.

Although earlier in the course of several fundamentalIn these studies, the effect of the excimer laser on the transformation of elements such as silicon was realized, and the laser effect on more complex compounds, such as SiC, was rarely studied due to the complexity of the phase transition of the compound and the ultra-short time during which this process takes place.

The above images obtainedThe Institute of Fundamental Science under a high-resolution microscope, along with the use of the molecular dynamics method, allowed researchers to discover how single-pulse radiation from an xenon chloride excimer laser melts silicon carbide in 30 nanoseconds and thereby leads to the release of a SiC liquid layer and a disordered carbon layer with graphite domain (about 2.5 nanometers in thickness) on the surface. A silicon layer is located under the carbon layer, the thickness of which is about 5 nanometers.

The use of additional pulses leads to the sublimation of the separated silicon, while the disordered carbon layer transforms into multilayer graphene.

Professor Keon notes that this study shows the possibilities of using laser technology to influence materials when creating new generations of two-dimensional nanomaterials.

Professor Choi complements the words of his colleague,emphasizing that the use of laser-induced phase separation as applied to complex compounds may in the future allow the synthesis of new types of two-dimensional nanomaterials.

Based on materials from sciencedaily.com