NSU Scientists Grow Aluminum Nitride Films

The scientific journal “Coatings” published the article “The chemical composition of the structure and physical properties of aluminum nitride films obtained by direct current pulsed reactive magnetron sputtering”. This article presents the research results from a study by scientists at the NSU Physics Department’s Analytical and Technological Research Center “High Technologies and Nanostructured Materials” (ATRC).   

The research was conducted at the Laboratory of Functional Diagnostics of Low-Dimensional Structures for Nanoelectronics as part of a government program to develop materials for information storage and transmission systems. Scientists conducted the first stage of the study obtaining films and the next stage that was associated with their detailed study and characterization. During the final stage of research, they obtained good quality films with the required smoothness, which is very important for the future use of the material.

Alena Bogoslovtseva, a Junior Researcher at the ATRC and second-year graduate student, talked about the results,

We managed to sel ect the operating mode for the installation that allowed us to obtain aluminum nitride films with good crystallinity and a high piezoelectric coefficient. We obtained films with good crystallinity and studied them using various methods. In our work producing aluminum nitride films, it was important for us to achieve the necessary smoothness; this is one of the important parameters for further work with this material. If you use a film with an insufficiently flat and smooth surface in the resonator, the signal will be lost and gradually fade, which is unacceptable. In addition, it was important for us to grow a film oriented strictly perpendicular to the substrate, since a deviation of even a few degrees significantly affects the properties of the film, namely, the speed of signal propagation and the piezoresponse. We successfully completed both tasks, and the next stage of development for our laboratory staff is to study the influence of sublayers on the grown film.

Aluminum nitride films are used in resonators of information transmission systems. Initially, this project was prepared and implemented by Laboratory staff together with the Omsk Research Institute of Instrumentation. The Omsk specialists grew the films and NSU scientists studied and characterized them. NSU ATRC had equipment that made it possible to grow aluminum nitride films, the Sputnik magnetron sputtering installation. Using this equipment, ATRC researchers conducted this work as part of a government assignment and it was decided to master the process of growing aluminum nitride films on site.

Bogoslovtseva summarized their work,

The fact that we were able to obtain good quality films using our installation makes us optimistic about further research. We intend, in collaboration with colleagues fr om other institutes, to move on to developing prototypes of resonators that will use multilayer structures and we have already begun work on their production. The resonator, which is our goal, is a multilayer structure. We have to practice spraying many layers on top of each other. Each layer must have certain properties, a given thickness and density, and the entire structure must be a single whole without delamination or microcracks. Its working layer, which performs the function of a piezoelectric transducer, will be a layer of aluminum nitride. Now that we have achieved it, our future work will be related to the development and selection of parameters for obtaining multilayer structures.