Microstructures Diagram Of Magnetron Sputtered Aln Deposits : Amorphous And Nanostructured Films

TL;DR

This study investigates the microstructures of aluminum nitride thin films deposited via magnetron sputtering, revealing four distinct microstructural types and their dependence on process parameters.

Contribution

It provides a detailed microstructure/process parameters map for AlN films, including amorphous and nanostructured types, based on systematic analysis.

Findings

Identified four microstructural types of AlN films.

Correlated microstructure with plasma working pressure and RF power.

Mapped process parameters to specific microstructures.

Abstract

In order to get homogeneous nanostructured Aluminum Nitride deposits, thin films were grown at room temperature on [001] Si substrates by radio frequency magnetron reactive sputtering. The deposits were analysed by Transmission Electron Microscopy, energy dispersive X-ray spectroscopy and Auger electron spectroscopy. Their microstructure and chemical composition were studied versus the plasma working pressure and the radio frequency power. Systematic analysis of cross views of the films allowed the authors to draw a microstructure/process parameters map. Four microstructural types were distinguished according to the decrease of the deposition rate. One is the well-known columnar microstructure. The second one is made of interrupted columns or fibrous grains. The third one is made of nano-sized particles (size of the particles ranges from 1.7 to 8 nm). The fourth and last microstructure is amorphous. The "deposit morphology-process parameters" correlation is commented on.