The objective of this work was to develop a process to pattern noble metal electrodes. To systematically investigate possible reactive etch process regions, characterized by volatile etch products, we used a reactive ion beam etching (RIBE) tool with a filament free ICP source. This configuration gives us exact control over the beam energy and the current density, and allows to use reactive gases. An energy dispersive quadrupole mass spectrometer is fitted to the chamber for in situ monitoring.
We study the influence of the beam energy and the beam current impinging on the wafer surface as well as it's angular dependence. Several additives to the chlorinated process chemistry are investigated and characterized in terms of their role to help to increase the etch rate, maintain a vertical profile, or to enhance process selectivity.
The main focus of the study is on Platinum. Blanket films were used to describe the influence of the material, and analysis were carried out to characterize the process in terms of etch rate, residues and selectivity.