Data for Hydrogen in aluminium oxide films grown for silicon surface passivation by plasma-enhanced atomic layer deposition

Post-deposition annealing is used to tune interfacial properties by modifying field-effect and chemical passivation. We have used time-of-flight elastic recoil detection analysis (ToF-ERDA) to depth-profile hydrogen concentrations in silicon coated with Al2O3 grown by plasma-enhanced ALD at 200 °C, with effective carrier lifetimes in the same sample set monitored by photoconductance decay measurements.

Effective lifetime — which strongly relates to surface passivation — peaks with post-deposition annealing at 450–500 °C. Corona charging experiments demonstrate that chemical passivation improves with annealing from 400 to 550 °C, worsening with annealing ≥600 °C. ToF-ERDA reveals an average hydrogen concentration of ∼1.2 at.% for films as-deposited and annealed ≤450–500 °C. As passivation starts to reduce upon annealing >550 °C, the film’s average hydrogen concentration reduces to ∼0.5 at.%, with no detectable increase in hydrogen in the silicon.