| Deposition Method | Processing | Surface | Bulk | |||
| Al (%) | O (%) | Al (%) | O (%) | O/Al | ||
| ALD | as deposited | 35.4 | 64.6 | 37.0 | 63.0 | 1.703 |
| 1050˚C anneal | 36.1 | 63.9 | 37.5 | 62.5 | 1.667 | |
| Plasma Assisted Evaporation | as deposited | 33.5 | 66.5 | 36.7 | 63.3 | 1.725 |
| 1050˚C anneal | 33.8 | 66.2 | 37.4 | 62.6 | 1.673 | |