Plasma surface treatment of local modify silicon plates

This paper presents a study of the use of silicon Si for element base manufacture of micro- and nanoelectronics by using combined methods of focused ion beams and atomic layer plasma chemical etching. This technology makes it possible to modify surface of Si substrates in the required topology and geometry, followed by removal of atoms to obtain nanoscale elements. The influence of parameters of method of focused ion beams and plasma chemical etching on parameters of the formed structures is analyzed. So, for example, for formation of structures with maximum roughness, it is necessary to increase values of parameters responsible for reactive ion etching, these are such parameters as: the power of capacitive plasma source, the mixing voltage, and the flow rate of an inert gas (argon).

Material Sputtering with a Multi-Ion Species Plasma Focused Ion Beam

Focused ion beams are an essential tool for cross-sectional material analysis at the microscale, preparing TEM samples, and much more. New plasma ion sources allow for higher beam currents and options to use unconventional ion species, resulting in increased versatility over a broader range of substrate materials. In this paper, we present the results of a four-material study from five different ion species at varying beam energies. This, of course, is a small sampling of the enormous variety of potential specimen and ion species combinations. We show that milling rates and texturing artifacts are quite varied. Therefore, there is a need for a systematic exploration of how different ion species mill different materials. There is so much to be done that it should be a community effort. Here, we present a publicly available automation script used to both measure sputter rates and characterize texturing artifacts as well as a collaborative database to which anyone may contribute. We also put forth some ideas for new applications of focused ion beams with novel ion species.

Imaging layers in thin-film molecular devices by transmission electron microscopy, using milling by focused ion beams and deposition on NaCl and Si

The performance of molecule-based thin-film devices such as organic light-emitting diodes, photovoltaic cells, and thin-film transistors depends on the electronic properties of the individual molecular components, as well as on their association to form complex morphologies. Transmission electron microscopy (TEM) can be used to image the morphologies and help reveal how the devices work and can be improved. We have examined the suitability of various ways to prepare samples of thin molecular films for imaging by TEM. Specifically, we have used focused ion beams to mill cross sections of complete devices that have been glued together with epoxy adhesives. In addition, thin films of the type used as active layers in molecule-based devices can be deposited on disks of NaCl, which can then be dissolved in water to release free-standing films that can be imaged by TEM, without loss of nanostructural details. Films of this type can also be deposited on Si wafers, which can then be fractured to expose sections of film that overhang edges of fragments and can be imaged conveniently by TEM. This allows TEM to be used as a quick method for screening samples and monitoring the purification of active materials.

Out-of-plane surface patterning by subsurface processing of polymer substrates with focused ion beams

This work explores a new technique for the out-of-plane patterning of nanostructures prefabricated on the surface of a polymer substrate. The technique is based on ion-beam-induced material modification in the bulk of a polymer. Effects of subsurface and surface processes on the surface morphology have been studied for three polymer materials (Polymethylmethacrylate, Polycarbonate and Polydimethylsiloxane) by using irradiations with He+, Ne+ and Ga+ focused ion beams. Thin films of a Pt60Pd40 -alloy and of pristine Au were used to mimic nanostructured thin films. We show that the height of thin Pt60Pd40 films deposited on Polymethylmethacrylate and Polycarbonate substrates can be patterned by He+ ion beam with nanometer precision while preserving nanometric features of the pre-deposited films. Ion irradiation of the Au-coated samples results in Au-film delamination, bulging and perforation, which is attributed to accumulation of radiolysis gases at the film-substrate interface. The irradiation with Ne+and Ga+ ions destroys the films and roughens the surface due to dominating sputtering processes. A very different behavior, resulting in the formation of complex, multiscale 3D- patterns, is observed for Polydimethylsiloxane samples. The roles of the metal film structure, elastic properties of the polymer substrate and irradiation-induced mechanical strain in the patterning process are elaborated and discussed.