Service de Physique de l'Etat Condensé

Graphene is a very promising material for a wide range of applications in Nanoelectronics.  Unfortunately, it presents a metallic character, which implies the need to look for alternative strategies in order to design and fabricate elementary electronic devices like diodes or transistors. This aspect constitutes a severe limitation in the field of numeric electronic or future telecommunications. A possible way to overcome this limitation is to consider new 2D materials in order to combine them with graphene eventually, in the design of future nanoelectronic devices. In this respect, phosphorene, a 2D material composed of one or several atomic layers of black phosphorous, offers a new opportunity to tackle this challenge. Indeed, phosphorene is a 2D semiconductor with very interesting properties compared to the ones of graphene. In particular, phosphorene combines in the meantime a direct bandgap, which is tunable as a function of the number of layers, and a high value of charge mobility. 

Until now, similarly to numerous 2D materials, phosphorene has mainly been obtained through exfoliation process. However, in order to obtain well-controlled phosphorene layers, procedures commonly used in industry like molecular beam epitaxy (MBE) and chemical vapour deposition (CVD) must be used to explore a large range of growing conditions and therefore to develop protocols adapted to the fabrication of new electronic devices.

In this context, three teams from Université Paris Saclay, namely ISMO-CNRS, TEMPO-Synchrotron SOLEIL and SPEC (CEA-CNRS), in collaboration with a group from Central Florida University, have achieved for the first time the synthesis of phosphorene chains on silver using MBE.