Electron beam surface patterning of Se alloys

Amorphous chalcogen alloys based on selenium (Se) and tellurium (Te) are extensively studied due to their unique physical properties. These materials find practical applications in infrared technologies, micro- and nano-electronics, nano-optics, photonics, and optoelectronics. Recently, laser and electron beam irradiations were shown to lead to surface mass transport or local density variations on Se-based amorphous alloys, and thus, to allow the surfaces of these chalcogen alloys to be patterned without the use of a mask such as for conventional lithography. The driving force of this phenomenon is assumed to be linked to charge accumulation in the irradiated regions, causing significant repulsion between ions in the film, leading to the local modification of the film volume or to mass transport in the vicinity of the film surface. In this work, room-temperature electron beam structuring effect is investigated on both amorphous and crystalline Se-rich chalcogen alloy thin films, exploring the potential of this technique for large-scale chalcogen alloy surface patterning, and providing new insights on the mechanism driving chalcogen alloy structuring by electron beam irradiations. • Amorphous Se alloys can be patterned by scanning electron beam without mask. • Electron beam-mediated patterns are partially crystallized. • Alloying Se with Te enables Se(Te) island aspect ratio to be tune. • E-beam patterning is suppressed in Se-rich alloys with low resistivity. • Optical diffraction tuning via organized Se island 2D pattern is demonstrated.