Development of a titanium plasma etch process for uncooled titanium nanobolometer fabrication

In this paper, we present our development of a BCl₃/Cl₂ plasma etch for defining nanoscale titanium (Ti) features using a LAM Research 9600 metal plasma etch chamber. The nanoscale Ti plasma etch is used, for the first time, to define Ti nanobolometer sensor features used in a novel IR sensor process. We characterised the nanoscale etch in terms of five primary process parameters using a 16-run V fractional factorial experiment, to provide good estimates of all main effects and two-factor interactions. The experimental results determined the target levels for the etch process parameters. Our optimised nanoscale Ti etch module was then integrated within a CMOS/MEMs-compatible nanobolometer infrared (IR) sensor fabrication flow.